Here, algae enjoy less upwelling and experience stronger iron limitation.
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Instead, new seismic measurements suggest it's an area of active upwelling.
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An asteroid impact likely triggered the upwelling of the salty liquid.
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More upwelling means more nutrient resupply, which means more biological activity, researchers say.
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There was a sudden, massive upwelling of air and debris, and everybody started to run.
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The latest upwelling of left-leaning religious activism has accompanied the dawn of the Trump presidency.
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Paul Krugman A funny thing is happening on the American scene: a powerful upwelling of decency.
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"It will likely take millions of years for the upwelling to get where it's going," Professor Levin explains.
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"As long as temperatures are increasing, these areas of upwelling will keep moving toward the Antarctic," said Trucchi.
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For now, it will remain a mystery, wrapped in an enigma, surrounded by an upwelling John Williams theme.
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This upwelling happens near a place called the Antarctic Polar Front — where icy Antarctic oceans meet the warmer Atlantic.
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Dorian has sat virtually stationary for 24 hours, & the core is not holding up over cold upwelling water pic.twitter.
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I'm feeling a general upwelling of love for all humankind, so I think then mushrooms are starting to kick in.
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However, climate affects precipitation patterns—which will affect the runoff from the Amazon—and natural factors like ocean upwelling patterns.
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And he is setting the stage for an upwelling of right-wing outrage, cuing up a crisis of electoral legitimacy.
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Deep seawater upwelling dominates the waters off the western coast of the Iberian Peninsula and keeps the coastal waters cool.
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"What we suspect is that the motion of the continent across the mantle is causing a draft, and upwelling," Menke said.
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"We found that higher atmospheric density, slower rotation rates, and the presence of continents all yield higher upwelling rates," Olson said.
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This freshwater creates a lens on the Gulf surface as well as the cooling effects of coastal upwelling due to wind stress.
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But in 2015, the expected upwelling of deep, cold water did not happen, Dr. Cobb said, speaking by satellite phone after her dive.
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One result of Karachi's new relative stability has been an upwelling of long-repressed dissent and complaints about the state of the city.
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Cooler water is drawn up from the depths to the surface in the Pacific's east as a result, in a process known as upwelling.
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"The bloom was likely caused by coastal upwelling, according to Oscar Schofield, a marine scientist at Rutgers University," NASA Earth Observatory said in a statement.
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El Nino conditions are normally propagated by an upwelling of warmer than average water from deep down in the ocean off the coast of Peru.
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Oceanic life on Earth depends on an upward flow, or upwelling, which moves nutrients from the dark depths to sunlit portions where photosynthetic life thrives.
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Researchers suggested the accelerated pace has to do with an oceanographic phenomenon called coastal upwelling in which wind sweeps deep waters up to the surface.
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The ocean currents off California tend to recirculate colder, more acidic water from deeper in the ocean to the surface, a process known as upwelling.
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This also gives him a rare vantage onto the city's latest upwelling of violence, which is concentrated in poor, overwhelmingly black West Baltimore—and is horrific.
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When she started, the northern population of the species was in trouble following a period of strong upwelling that brought unusually cold water to the surface.
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Cold waters deep in the equatorial Pacific move eastward towards the Americas, causing the upwelling, or surfacing, of these cool waters off the coast of Peru.
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They can't guarantee that every dome they measured is really an ice volcano—and there are probably non-dome-shaped cryovolcanic features, like volcanic upwelling after impacts.
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As the warmer surface waters are driven off by the trade winds they expose and are replaced by an upwelling of colder water from the deep ocean.
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The complex current that flows through underwater canyons can create a nutrient-rich upwelling and mixing that makes life remarkably diverse to these parts of the ocean.
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Acidification is an even bigger problem on the Pacific Coast due to upwelling, in which the wind drives corrosive waters from the depths upward, impacting coastal fisheries.
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The model also greatly underestimates a similar area of upwelling off of the African coast that induces the tropical Atlantic's version of El Niño, known as the Atlantic Niño.
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Climate models that substantially underestimate the natural cold upwelling have a propensity to create El Niño-like conditions, which may explain their tendency to predict too much global warming.
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For example, the disastrous turn toward austerity after 2009 was a kind of natural experiment that led to an upwelling of good work on the effects of fiscal policy.
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Editorial Observer Los Angeles — The current political moment, with its upwelling of nationalism and xenophobia, has a repellent taste, like a mouthful of citrus pith, all bitter and white.
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The paper suggests, for instance, that nutrient upwelling from stellar-induced tides might trigger massive algae blooms, offering astronomers a potential biosignature that we could spot from afar using telescopes.
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Since water is denser than most of the stuff found at or near Pluto's surface, that upwelling would have increased the relative mass of Sputnik Planitia rather than decreasing it.
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La Niña, the opposite of El Niño, occurs when circulations are at their strongest, with strong trade winds, more upwelling and more cold water carried further into the central ocean.
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A renaissance of sorts got underway, an upwelling of pride that became ever more energized as the canoe's navigational achievements and successes — all still performed with no instrumental help — accumulated.
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In fact, the upwelling of worry among investors and the broader public reflects the bumpy economic terrain and represents one of the more bullish factors in equities' favor at the moment.
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Buoyed by charm and a conservative upwelling in Colombia, he secured the presidency in an election where many who voted for him did not even know his name a year ago.
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Filmmakers Rachel Lears and Robin Blotnick set out capture that upwelling of political activity during the 2018 midterm elections, not necessarily memorialize Ocasio-Cortez' comet-like trajectory as it unfolded in real time.
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" He also suspects "the scarcity of pure plays in the public market" for space companies may be combining "with an upwelling of investor sentiment around human spaceflight," contributing to the stock's "extraordinary rise.
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Interestingly, this same kind of upwelling of nutrients from deep waters happens naturally along the California coast as a consequence of strong ocean currents, rather than the effects of scorching hot molten lava.
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Runoff from the glaciers would have washed nutrients like iron into coastal waters and intense seasonal upwelling cycles would have caused cold water from deep below to rise, bringing organic material toward the surface.
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An extraordinary upwelling of activism in support of Indian land rights and expressing environmental concerns — focused on blocking the planned path of the multi-billion-dollar Dakota Access Pipeline — achieved a remarkable victory today.
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"The upwelling we detected is like a hot-air balloon, and we infer that something is rising up through the deeper part of our planet under New England," says Rutgers University geophysicist Professor Vadim Levin .
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The Saturday mission, named "AZURE" for the Auroral Zone Upwelling Rocket Experiment, launched from Norway's Andøya Space Center just after midnight local time, and after several attempts in 2018 were scuttled due to bad weather.
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Pictures of a disheveled looking Huong leaving court in a bulletproof vest on Wednesday brought an upwelling of sympathy in Vietnam and drew widespread calls on social media for more to be done for her.
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But Chris Walsh of Revolutionary Realty says growing demand has turned into such a "massive upwelling" that he now sells about 140 properties a year in the north-western part of the Redoubt, its heart.
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Oceanic crust, where the telltale mantle exchange zones are located, is recycled through the upwelling and subducting pipeline every 200 million years or so, which means hard evidence of tectonic origins was destroyed long ago.
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Southern New England lobsters once were protected from the warm water temperatures in Long Island Sound by upwelling from the Labrador current that tucked in along the coast of eastern Connecticut, Rhode Island and southern Massachusetts.
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It was my belief then, and it is my belief now after 40 years of working towards this, that this will bring about a great change and great upwelling of creative work once it is accomplished.
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Trilobites Their little chicks fast for more than a week while they forage for fish and krill in the waters of the Antarctic polar front, an upwelling where cold, deep seas mix with more temperate seas.
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The Canary Islands are likely caused by an upwelling of hot mantle material called a hot spot (or mantle plume), creating a chain of volcanoes as the African Plate moves (much like how the Hawaiian Islands are formed).
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What's more, the same upwelling of heat that allows these great polynyas to form could also find its way to the increasingly vulnerable Antarctic ice shelves — which are the ends of giant glaciers that float over the ocean.
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It could be caused by action along a tectonic plate boundary, an upwelling plume of superheated mantle material, or even an extension of the East African Rift, a major tectonic event that's slowly tearing the continent apart, said Hicks.
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Recognizing this complex phenomenon, I can begin to understand the great upwelling of working-class support for Bernie Sanders and Donald J. Trump — especially for the latter in regions of postindustrial America left behind by these jarring economic dislocations.
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The shifts would cut the productivity of fisheries in 2300 by an average 20 percent and by 60 percent in the North Atlantic, where a normal upwelling of nutrients from deeper waters would be most reduced, according to computer simulations.
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However, because the storm is going to stall for several days, its winds are likely to drag cooler waters up from deeper layers of the Atlantic through a process known as upwelling, which could then weaken it significantly by midweek.
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Likely due to ocean upwelling from El Nino conditions, the Northern kelp crabs found themselves in the Channel Island waters Teall tends to fish in, where they survived on a diet of exclusively red kelp, and thus, their shells turned fire-truck red.
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Redistricting has placed Representative Keith Rothfus, a Republican, on the same turf as Representative Conor Lamb, a Democrat, whose upset victory in a special election in March in deepest Trump country was evidence of the upwelling of Democratic momentum in the midterms.
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Residents say the upwelling is rooted in fears that their ability to reunify has been slowly slipping away ever since India increased its control of the divided territory and Pakistan did little to stop it other than to offer negotiations that India refused.
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So, a research team used the software to identify "which (types of) planets will have the most efficient upwelling and thus offer particularly hospitable oceans," Stephanie Olson, lead researcher at the University of Chicago, said Thursday while presenting the research at the Goldschmidt Geochemistry Conference in Barcelona.
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Europa is also a geologically active world, so samples of the buried ocean may routinely make it to the surface — via localized upwelling of the ocean itself , for example, and/or through geyser-like outgassing, evidence of which has been spotted multiple times by NASA&aposs Hubble Space Telescope.
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That constant upwelling of emotion is largely the fault of its soaring songbook, much of which was written by the now-famed Hamilton librettist, along with veteran Hollywood composer Mark Mancina and Opetaia Foa'i, the New Zealand-based Pacific music singer-songwriter (for whom Moana is his first IMDB credit).
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"What we've got here is a small but genuine hashtag campaign, which is being exaggerated and amplified by Russian state propaganda outlets to make it look like the campaign is huge and an upwelling of popular anger," said Nimmo, who works for the Digital Forensic Research Lab of the Washington-based Atlantic Council think tank.
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Serious plein air artists like Heidkamp, who are cognizant of 20th and 21st century shifts in the language and intent of painting, yet choose to take on the furious flux of the upwelling world, are staking out a territory that represents — in the full sense of re-presenting — an art that joins what we see with what we feel.
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Scientists have seismic evidence that the deep part of the mantle is a graveyard where long ago slabs of earth were subducted, or thrust underneath one another, creating separate regions with different chemical compositions that eventually made their way to the surface in a hot mantle plume, or upwelling, as the core heated the rock into magma.
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Indeed, the results of the poll represent the same upwelling of discontent that inspired millions of Americans to protest as a part of the Tea Party and Occupy Wall Street movements — the same frustration that gave a candidate like Bernie SandersBernie SandersJoe Biden faces an uncertain path Bernie Sanders vows to go to 'war with white nationalism and racism' as president Biden: 'There's an awful lot of really good Republicans out there' MORE a fighting chance in the Democratic primaries and ultimately led to the election of an outsider like Trump.
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Areas of upwelling in red The major upwellings in the ocean are associated with the divergence of currents that bring deeper, colder, nutrient rich waters to the surface. There are at least five types of upwelling: coastal upwelling, large-scale wind- driven upwelling in the ocean interior, upwelling associated with eddies, topographically-associated upwelling, and broad-diffusive upwelling in the ocean interior.
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The Upwelling is an eponymous EP album by the group The Upwelling released in 2004.
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Certain effects of strong and weak upwelling affect the bocaccio's food sources and the survival of its larvae. Larval rockfish are abundant in or near front upwelling fronts. When the water is cold the upwelling is strong with more productivity and warmer water produces a weaker upwelling with a low amount of resources. Also, a weak upwelling may affect reproduction in egg size, egg amount, and egg quality.
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Coastal upwelling is the main factor contributing to the high biological productivity of the Humboldt current. Upwelling within the current is not uniform across the entire system. Three notable upwelling subsystems are produced by this current: # seasonal upwelling in Chile only during the spring and summer, because of the displacement of the subtropical center of high pressure during the period January–March, # upwelling "shadow" that is less productive, but still large in northern Chile and Southern Peru, and # highly productive year-round upwelling in Peru. The upwelling shadow identified between 35°S and 15°S is caused by the oligotrophic subtropical gyre impinging on the coast.
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Every summer, the upwelling sustains a bountiful ecosystem that attracts blue whales and supports rich fisheries. The Great South Australian Coastal Upwelling System (GSACUS) is Australia's only deep- reaching coastal upwelling system, with nutrient-enriched water stemming from depths exceeding .Kämpf, J., 2010. On the preconditioning of coastal upwelling in the eastern Great Australian Bight.
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Accessed 12 July 2013. Upwelling events occur nearly simultaneously across the three separate centres, appearing within a few days of each other, despite spanning a distance of approximately . While the Bonney Upwelling, where the strongest and most reliable upwelling events occur, was reported and explored over 30 years ago,Lewis, R.K. 1981. Seasonal upwelling along the south-eastern coastline of South Australia.
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Phytoplankton blooms on the western shelf of Tasmania: evidence of a highly productive ecosystem, Ocean Sci., 11, 1-11. Since this new upwelling centre is located outside South Australian waters, the entire upwelling system should be rather called the Great Southern Australian Coastal Upwelling System.
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Upwelling in these two regions has been modelled to be in antiphase, an effect known as "upwelling see-saw".Prange, M., and M. Schulz. "A coastal upwelling seesaw in the Atlantic Ocean as a result of the closure of the Central American Seaway." Geophysical Research Letters 31.17 (2004).
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Atlantic DSi depleted waters tends to produce relatively less silicified organisms, which has a strong influence on the preservation of their frustules. This mechanism in best illustrated when comparing the Peru and northwest Africa upwelling systems. The dissolution/production ratio is much higher in the Atlantic upwelling than in the Pacific upwelling. This is due to the fact that coastal upwelling source waters are much richer in DSi off Peru, than off NW Africa.
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Upwelling intensity depends on wind strength and seasonal variability, as well as the vertical structure of the water, variations in the bottom bathymetry, and instabilities in the currents. In some areas, upwelling is a seasonal event leading to periodic bursts of productivity similar to spring blooms in coastal waters. Wind-induced upwelling is generated by temperature differences between the warm, light air above the land and the cooler denser air over the sea. In temperate latitudes, the temperature contrast is greatly seasonably variable, creating periods of strong upwelling in the spring and summer, to weak or no upwelling in the winter.
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For example, off the coast of Oregon, there are four or five strong upwelling events separated by periods of little to no upwelling during the six-month season of upwelling. In contrast, tropical latitudes have a more constant temperature contrast, creating constant upwelling throughout the year. The Peruvian upwelling, for instance, occurs throughout most of the year, resulting in one of the world's largest marine fisheries for sardines and anchovies. In anomalous years when the trade winds weaken or reverse, the water that is upwelled is much warmer and low in nutrients, resulting in a sharp reduction in the biomass and phytoplankton productivity.
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The upwelling front is accompanied by a geostrophic upwelling jet. During the summer upwelling season, the southward flowing jet off of central Oregon lies mid-shelf at approximately the 100-m isobath. Its near-surface speed averages 0.35 m/s, with individual events exceeding 0.80 m/s. This is faster than the surrounding water velocity.
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Major upwelling occurs between 23 and 25 degrees northern latitude (Canary Current, 2002). Upwelling occurs year-round at Cap Blanc (Ras Nouadhibou) and northward. South of Cap Blanc, upwelling is limited to winter and spring due to the northward migration of the Azores high during summer, which is responsible for driving equatorward winds. Minas et al.
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Large swarms of krill, Nyctiphanes australis, form during upwelling events. An abundance of krill makes the Bonney Upwelling an important feeding site for the blue whale (Balaenoptera musculus) Extensive upwelling of nutrient-rich water makes the GSACUS an important marine hot spot on Australia's southern shelves. During upwelling events, the abundance of the GSACUS ecosystem can approach that of some of the world’s most productive upwelling centers, such as those offshore of Peru, California, and Namibia.Ward, T. M., McLeay, L. J., Dimmlich, W. F., Rogers, P. J., McClatchie, S., Matthews, R., Kämpf, J. and Van Ruth, P. D. (2006), Pelagic ecology of a northern boundary current system: effects of upwelling on the production and distribution of sardine (Sardinops sagax), anchovy (Engraulis australis) and southern bluefin tuna (Thunnus maccoyii) in the Great Australian Bight.
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This event is known as the El Nino-Southern Oscillation (ENSO) event. The Peruvian upwelling system is particularly vulnerable to ENSO events, and can cause extreme interannual variability in productivity. Changes in bathymetry can affect the strength of an upwelling. For example, a submarine ridge that extends out from the coast will produce more favorable upwelling conditions than neighboring regions.
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The intrusion of warm waters from the Mozambique Channel may reduce the upwelling at the south of Madagascar surface signature during the austral summer season. Intensification of wind stress curl could favor the intrusion of the SMACC toward the upwelling system. Consequently, the intensification of the wind stress curl enhances the transport of warm water, carried by the SMACC, reduces the surface signature of the upwelling, and influences the phytoplankton response associated with that upwelling. The interaction between the SMACC and the coastal upwelling could influence the local fisheries productivity and larval transport patterns, as well as the connectivity with the Agulhas Current, affecting the returning branch of the global overturning circulation.
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Buoyancy, and hence gravity, are responsible for the appearance of convection cells. The initial movement is the upwelling of lesser density fluid from the heated bottom layer. This upwelling spontaneously organizes into a regular pattern of cells.
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Cyclonic eddies is another source of edge upwelling west of Port Elisabeth. Plumes of warm surface water migrate onto the bank along its eastern edge, providing subtropical surface water from the Indian Ocean. In summer, easterly winds can intermittently drive coastal upwelling along the South African south coast. The Agulhas Bank is dominated by westerly winds and most of the upwelling on the bank is related to the interaction of the Agulhas Current on the eastern edge, but easterly winds do occur, especially in summer and fall, and can generate local upwelling cells.
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Coastal upwelling s also common on the western bank, but the more stable atmospheric condition results in larger cold water plumes that sometimes merge to form a continuous upwelling regime along the South African south-west coast. This upwelling zone is the southernmost extension of the Benguela Current Large Maritime Ecosystem. The Agulhas Current regularly flows around the southern tip of the bank and brings warm water to the western bank along the bank's western edge. Regularly, the mesoscale eddies from the east interact with the Benguela upwelling system on the African west coast.
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Coastal upwelling of the South Eastern Arabian Sea (SEAS) is a typical eastern boundary upwelling system (EBUS) similar to the California, Bengulea, Canary Island and Peru-Chili systems. Unlike those four, the SEAS upwelling system needs to be explored in a much focused manner to clearly understand the chemical and biological responses associated with this coastal process. The coastal upwelling in the south-eastern Arabian Sea occurs seasonally. It begins in the mid Spring (Mid May) along the southern tip of India and as the season advances it spreads northward.
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For reasons of conservation of mass, the global ocean system must upwell an equal volume of water to that downwelled. Upwelling in the Atlantic itself occurs mostly due to coastal and equatorial upwelling mechanisms. Coastal upwelling occurs as a result of Ekman transport along the interface between land and a wind-driven current. In the Atlantic, this particularly occurs around the Canary Current and Benguela Current.
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Nonetheless, some diffusive upwelling does probably occur. Location of the Southern Ocean gyres.
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Environmental conditions, satellite imagery, and clupeoid recruitment in the northern Benguela upwelling system.
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Chemical factors include oxygen and trace elements. Biological factors include grazing and migrations. Upwelling carries nutrients from the deep waters into the photic zone, strengthening phytoplankton growth. The remixing and upwelling eventually bring nutrient-rich wastes back into the photic zone.
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The GSACUS supports a productive fishery, and local fishers recognize the bounty that the upwelling provides them. Every November, Portland, Victoria, hosts an Upwelling Festival to celebrate the abundance of the Bonney Upwelling, and to begin the summer fishing season. Humans have exploited the GSACUS for thousands of years. Oral histories of local Aboriginal tribes indicate a close connection to the ocean, and said tribes may possibly have eaten beached whales.
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Mean chlorophyll-a concentration map of the oceans surrounding Southern Africa. Note the very high concentrations along the west coast, due to the upwelling of mineral rich water from the cold depths the South Atlantic Ocean, forming the Benguela Current.Northward winds along the coast result in Ekman transport offshore and upwelling of nutrient rich deep water to the euphotic zone. The intensity of the upwelling event is determined by wind strength.
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Siliceous oozes form in upwelling areas that provide valuable nutrients for the growth of siliceous organisms living in oceanic surface waters. A notable example is in the Southern ocean where consistent upwelling of Indian, Pacific, and Antarctic circumpolar deep water have resulted in a contiguous siliceous ooze that stretches around the globe. There is a band of siliceous ooze that is the result of enhanced equatorial upwelling in Pacific Ocean sediments below the North Equatorial Current. In the subpolar North Pacific, upwelling occurs along the eastern and western sides of the basin from the Alaska current and the Oyashio Current.
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Upwelling at Kangaroo Island and the Eyre Peninsula is different than at the Bonney Upwelling. Here, the continental shelf is generally much wider than at the Bonney Coast - up to wide off the Eyre Peninsula - and water is not drawn directly from the seafloor to the surface. Instead, field data and hydrodynamic modelling suggest that the upwelling follows from a chain of processes. This chain of processes starts in the deep submarine canyons of the Murray Canyon Group, located south of Kangaroo Island, where localized sub-surface upwelling brings a pool of cold water from the abyssal plains up to the continental shelf.
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Upwelling carries nutrient rich, and cold deep- sea water to the euphotic zone, promoting phytoplankton blooms and kickstarting an extremely high-productive environment. Areas of upwelling leads to the promotion of fisheries, in fact nearly half of the world's fish catch comes from areas of upwelling. Ekman suction occurs both along coastlines and in the open ocean, but also occurs along the equator. Along the Pacific coastline of California, Central America, and Peru, as well as along the Atlantic coastline of Africa there are areas of upwelling due to Ekman suction, as the currents move equatorwards.
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Variations in wind strength cause pulses of upwelling, which propagate to the south along the coast with speeds of 5 to 8 m/s. The pulses are similar to a Kelvin wave, except on a scale of 30 to 60 km instead of 1000 km, and can propagate around the cape depending on wind systems. Pulses of upwelling induce biological production. In the Benguela system, phytoplankton growth requires a period of upwelling followed by a period of stratification and relatively calm waters. The phytoplankton bloom usually lags the upwelling event by 1 to 4 days and blooms for 4 to 10 days.
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Hogg et al. (2013), p. 1898. The effect is strengthened by strong upwelling around Antarctica.
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In many numerical models and observational syntheses, the Southern Ocean upwelling represents the primary means by which deep dense water is brought to the surface. In some regions of Antarctica, wind-driven upwelling near the coast pulls relatively warm Circumpolar deep water onto the continental shelf, where it can enhance ice shelf melt and influence ice sheet stability. Shallower, wind-driven upwelling is also found in off the west coasts of North and South America, northwest and southwest Africa, and southwest and south Australia, all associated with oceanic subtropical high pressure circulations (see coastal upwelling above). Some models of the ocean circulation suggest that broad-scale upwelling occurs in the tropics, as pressure driven flows converge water toward the low latitudes where it is diffusively warmed from above.
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Upwelling and primary production follow the onset of a strong wind within a few days (Mann & Lazier, 1996). Zooplankton, such as copepods, take longer to respond to the abundance of food available because they have life cycles of weeks rather than days. Zooplankton in the Canary Current reach their peak density in autumn when upwelling intensity decreases. The decrease in upwelling allows the zooplankton to stay over the shelf where their food supply exists.
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Inshore of the Benguela Current proper, the south easterly winds drive coastal upwelling, forming the Benguela Upwelling System. The cold, nutrient rich waters that upwell from around 200–300 m depth in turn fuel high rates of phytoplankton growth, and sustain the productive Benguela ecosystem.
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Primary production to the south of Cap Blanc is limited by the occurrence of upwelling events.
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During the normal period and La Niña events, the easterly trade winds are still strong, which continues to drive the process of upwelling. However, during El Niño events, trade winds are weaker, causing decreased upwelling in the equatorial regions as the divergence of water north and south of the equator is not as strong or as prevalent. The coastal upwelling zones diminish as well since they are wind driven systems, and the wind is no longer a very strong driving force in these areas. As a result, global upwelling drastically decreases, causing a decrease in productivity as the waters are no longer receiving nutrient-rich water.
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Rather, the primary source of nitrate into the estuary is from ocean exchange caused by wind-driven seasonal upwelling off the Oregon and Washington coasts. This influx of nitrate, generally the primary limiting nutrient to biological communities in the estuary, is an important driver of primary productivity in estuarine plumes of river discharge. Moreover, large scale upwelling on the Oregon-Washington coast typically occurs in spring and summer, and as discussed previously, is coupled with the PDO and ENSO, this seasonal upwelling further contributes to diatom bloom in the estuary. Finally, without this source of nitrogen through upwelling, the estuary quickly becomes nitrate limited and hinders further facilitation of biological activity.
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There is year- round upwelling off Southern California's coast, but it is strongest in the summer months. Off the coast of Oregon and Washington, there is forceful downwelling in the winter months, and upwelling in the region is restricted to the months of April through September.
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The most productive and fertile ocean areas, upwelling regions are important sources of marine productivity. They attract hundreds of species throughout the trophic levels; these systems' diversity has been a focal point for marine research. While studying the trophic levels and patterns typical of upwelling regions, researchers have discovered that upwelling systems exhibit a wasp- waist richness pattern. In this type of pattern, the high and low trophic levels are well-represented by high species diversity.
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These animals feed predators such as seabirds, fishes, Australian fur seals, and penguins. The upwelling plays also an important role in the life cycle of juvenile southern bluefin tuna (Thunnus maccoyii), which accumulate in the eastern Great Australian Bight during the upwelling season and feed on sardines (Sardinops sagax) and anchovies (Engraulis australis).Willis, J., and Hobday, A. J. (2007). Influence of upwelling on movement of southern bluefin tuna (Thunnus maccoyii) in the Great Australian Bight.
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The three main drivers that work together to cause upwelling are wind, Coriolis effect, and Ekman transport. They operate differently for different types of upwelling, but the general effects are the same. In the overall process of upwelling, winds blow across the sea surface at a particular direction, which causes a wind-water interaction. As a result of the wind, the water has transported a net of 90 degrees from the direction of the wind due to Coriolis forces and Ekman transport.
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In contrast, to the right of the center of the jet, more water is coming from the center than is leaving, creating a downwelling event (Ekman pumping). This open-ocean upwelling in combination with the coastal upwelling cause a massive upwelling. The Northeast monsoon, which occurs from December to February, causes a reversal of the Somalia current, moving the coastal waters southwest. Cooler air causes the surface water to cool and creates deep mixing, bringing abundant nutrients to the surface.
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Thus, upwelling occurs to replace the coastal surface water, bringing cold, nutrient rich water up from the seafloor. During the winter months when winds primarily flow to the north, downwelling becomes the dominant system. Downwelling acts in the opposite manner of upwelling, transporting coastal surface water to depth. The spring transition from the winter downwelling-dominant system to the summer upwelling-dominant system is quick and includes a sudden drop in sea level of around 10 cm in just a few days.
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Key upwelling centres form in three different locations, described in the sub- sections below; the Kangaroo Island and Eyre Peninsula centres are linked by the same upwelling process.Butler, A. J., F. Althaus, D. M. Furlani, and K. R. Ridgway. Assessment of the Conservation Values of the Bonney Upwelling Area: A Component of the Commonwealth Marine Conservation Assessment Program 2002-2004: Report to Environment Australia. Published by CSIRO Marine Research (now CSIRO Marine and Atmospheric Research) and Environment Australia, Dec. 2002.
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Upwelling typically begins at such ridges and remains strongest at the ridge even after developing in other locations.
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The prime fishing area, characterized by upwelling nutrient-rich cold water, has moved south along the Namibian coast.
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Australian Journal of Marine and Freshwater Research 32: 843-854. the full extent of the upwelling system was discovered only as recently as 2004.Kämpf, J., M. Doubell, D. Griffin, R. L. Matthews & T. M. Ward, 2004. Evidence of a large seasonal coastal upwelling system along the Southern Shelf of Australia.
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Without these nutrients, the rest of the trophic pyramid cannot be sustained, and the rich upwelling ecosystem will collapse.
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Ekman Suction is the component of Ekman transport that results in areas of upwelling due to the divergence of water. Returning to the concept of mass conservation, any water displaced by Ekman transport must be replenished. As the water diverges it creates space and acts as a suction in order to fill in the space by pulling up, or upwelling, deep sea water to the euphotic zone. Ekman suction has major consequences for the biogeochemical processes in the area because it leads to upwelling.
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Unlike most other major ocean currents, there is no large- scale coastal upwelling associated with the Leeuwin Current. There is limited evidence for some sporadic, localised upwelling in the vicinity of the Abrolhos, but if so it appears to have little effect on the extremely low levels of nutrients in the water.
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Marshall, John, and Kevin Speer. "Closure of the meridional overturning circulation through Southern Ocean upwelling." Nature Geoscience 5.3 (2012): 171.
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Areas with coastal upwelling such as the west coast of North America have experienced increases in acidification due to more acidic deep water upwelling into the estuary. This may have a detrimental effect on the survival of calcifying organisms because the organisms have a much more difficult time forming and maintaining their calcium carbonate shells.
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The Bonney Upwelling is the largest and most predictable upwelling in the GSACUS. It stretches from Portland, Victoria to Robe, South Australia. The continental shelf is narrow offshore of the "Bonney Coast" - only about from the shore to the continental slope - and deep water is funneled to the surface through a series of submarine canyons.
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Superplume/superswell creation is a large upwelling of material. Normal upwellings in the mantle are a common occurrence, as it is generally accepted that these upwellings are the driving force behind mantle convection and subsequent plate motion. In the case of the upwelling in the mid-Cretaceous Period along the East Pacific Rise, its origin lies deep within the earth, near the core–mantle boundary. This conclusion is taken from the fact that the earth retained a constant field polarity at the same time that this upwelling occurred.
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If this net movement of water is divergent, then upwelling of deep water occurs to replace the water that was lost.
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Despite this new currents and deep ocean upwelling favored the diversification of modern cetaceans such as early toothed and baleen whales.
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The Yaquina Bay estuarine chemistry is influenced by daily tides, river sediment input, summer upwelling along the coast, and biological processes.
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A prominent feature of Eastern Boundary Currents is the presence of upwelling. Ekman drift causes offshore transport of surface waters, which are then replaced with deep water from below. Deep waters are cold and nutrient-rich and have a key role in stimulating primary productivity. Upwelling has led to the enhancement of coastal fisheries in western Morocco (Hance, 1975).
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There is one additional effect of turbidity currents: upwelling. All of the water rushing into ocean valleys displaces a significant amount of water. This water literally has nowhere to go but up. The upwelling current goes almost straight up. This spreads the nutrient rich ocean life to the surface, feeding some of the world’s largest fisheries.
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Map of Australia, showing the Great Australian Bight Great Australian Bight The Great South Australian Coastal Upwelling System is a seasonal upwelling system in the eastern Great Australian Bight, extending from Ceduna, South Australia, to Portland, Victoria, over a distance of about . Upwelling events occur in the austral summer (from November to May) when seasonal winds blow from the southeast. These winds blow parallel to the shoreline at certain areas of the coast, which forces coastal waters offshore via Ekman transport and draws up cold, nutrient-rich waters from the ocean floor. Because the deep water carries abundant nutrients up from the ocean floor, the upwelling area differs from the rest of the Great Australian Bight, especially the areas offshore of Western Australia and the Nullabor in South Australia, which are generally nutrient-poor.
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The required diffusion coefficients, however, appear to be larger than are observed in the real ocean. Nonetheless, some diffusive upwelling does probably occur.
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Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers.
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The presence of abundant chert and phosphate minerals in the group is attributed to upwelling along the continental margin, possibly triggered by glaciation.
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The Auroral Zone Upwelling Rocket Experiment in April 2019 caught many Norwegians by surprise by triggering an unusual form of the Aurora Borealis.
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South Africa Topography A more current superplume/superswell is in the southern and eastern region of Africa. Seismic analysis shows a large low-shear-velocity province, which coincides with a region of upwelling of semi-liquid material which is a poor conductor of seismic waves. While there are several processes at work in the formation of these high topography zones, lithospheric thinning and lithospheric heating have been unable to predict the topographic upwelling on the African plate. Dynamic topography models have, on the other hand, been able to predict this upwelling utilizing calculations of the instantaneous flow of Earth's mantle.
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Upwelling is an oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface, replacing the warmer, usually nutrient-depleted surface water. The nutrient-rich upwelled water stimulates the growth and reproduction of primary producers such as phytoplankton. Due to the biomass of phytoplankton and presence of cool water in these regions, upwelling zones can be identified by cool sea surface temperatures (SST) and high concentrations of chlorophyll-a. The increased availability of nutrients in upwelling regions results in high levels of primary production and thus fishery production.
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A major threat to both this crucial intermediate trophic level and the entire upwelling trophic ecosystem is the problem of commercial fishing. Since upwelling regions are the most productive and species rich areas in the world, they attract a high number of commercial fishers and fisheries. On one hand, this is another benefit of the upwelling process as it serves as a viable source of food and income for so many people and nations besides marine animals. However, just as in any ecosystem, the consequences of over-fishing from a population could be detrimental to that population and the ecosystem as a whole.
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Coronae are large, circular structures with concentric fractures around them that result from mantle upwelling followed by extensional collapse. Since many sequences of upwelling and collapse have been observed as structurally different coronae on Venus' surface, all coronae appear to share a sequence of heavy volcanism as a result of upwelling, topographic rise, tectonic deformation, subsidence due to gravitational collapse, and continued volcanism. Coronae on Venus differ in the location of topographic uplift, and have been characterized as such. Topographic uplift may occur in the depression, the rim, the outer rim, or a combination of these locations.
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Compared to the Agulhas Current, the Benguela Current on the west and south-west coast of Africa is more intense and steadier. Its dynamic southern upwelling system is driven by the prevailing northward winds that produce an intense off-shore Ekman transport. Most of this upwelling is concentrated to a few upwelling cells in the southern region: Namaqua (30°S), Cape Columbine (32.5°S), and Cape Peninsula (34°S). The wind is most intense from October to February, and the contrast in sea surface temperature between the open sea and the shelf is most prominent during summer.
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This form of upwelling forces cold deep water up onto the continental shelf, but not necessarily above the thermocline. In the region east of the Agulhas bank, wind enhanced upwelling, occurring mainly in summer, augments the current driven upwelling bringing the colder deeper waters to the surface. This enhances biological productivity by supply of nutrients to the euphotic zone (where plants have sufficient light to flourish) which fuels phytoplankton production, and rocky shores that are supplied with the nutrient rich water support rich algal biomass. There are a large proportion of species endemic to South Africa along this coastline.
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In contrast to the southward upwelling jet, the northward downwelling jet has a reduced velocity. Therefore, its path around the bank is not as strong and noticeable, resulting in less offshore deflection and no reversed currents, as seen during upwelling conditions. Inshore of the jet is an area of well-mixed water. Overall, the bank is an area of decreased downwelling strength.
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Vo. 129A, pp.125-135 Events such as wind driven upwelling and downwelling also affect meroplankton species distribution. Most species are swept in the direction of the flow of water, either off shore during an upwelling or near shore during a downwelling. Some species, such as bivalve larvae, have the ability to maintain their nearshore position during these events.10\.
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Large-scale upwelling is found in the Southern Ocean. Strong westerly (eastward) winds blow around Antarctica, driving a significant flow of water northwards. This is actually a type of coastal upwelling. Since there are no continents in a band of open latitudes between South America and the tip of the Antarctic Peninsula, some of this water is drawn up from great depths.
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Such distribution of particles and animals can be described using mathematical model developed by Stommel that suggested area of retention on upwelling zone for sinking particles and on downwelling zone for positively buoyant particles. Actually, the zooplankton could become trapped in upwelling zones to a point where animals are stimulated to swim downwards.Hutchinson, G. E. (1967). A treatise on Limnology, Vol.
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Its middle and upper Miocene upwelling-rich assemblages, and its unique highly siliceous rocks from diatom-rich plankton, became diatomites, porcelainites, and banded cherts.
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Australian Broadcasting Company, 2007. Accessed 16 July 2013. Other marine life that thrives in the upwelling includes filter feeders like sponges, bryozoans, and corals.
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El Niño and La Niña effect of the upwelling due to the drastic changes in the warmth of water. They also get affected by overfishing.
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The eddies size and strength decline with distance from major ocean currents. The amount of energy decreases from the rings associated with the major currents and down to eddies remote from those currents. Cyclonic eddies have the potential to cause upwelling that would affect the global primary-production budget. Upwelling brings cold, nutrient-rich water to the surface resulting in an increase in productivity.
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Large-scale upwelling is also found in the Southern Ocean. Here, strong westerly (eastward) winds blow around Antarctica, driving a significant flow of water northwards. This is actually a type of coastal upwelling. Since there are no continents in a band of open latitudes between South America and the tip of the Antarctic Peninsula, some of this water is drawn up from great depths.
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The absorption, reflection and scattering characteristics of the atmosphere were determined by measuring the extraterrestrial solar irradiance and the upwelling radiance observed in different viewing geometries. The ratio of extraterrestrial irradiance and the upwelling radiance can be inverted to provide information about the amounts and distribution of important atmospheric constituents, which absorb or scatter light, and the spectral reflectance (or albedo) of the Earth's surface.
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Most of the time, the trade winds drive surface waters offshore near the equator, driving the Humboldt Current from the tip of southern Chile to northern Peru. This current is associated with upwelling of deep, nutrient-rich water off the coast of Peru. At times, El Niño disrupts the usual wind pattern and lessens the upwelling. The consequent loss of nutrient causes fish kills.
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Fisheries Oceanography, 15: 191–207. During upwelling events, surface chlorophyll a concentrations, an indicator of phytoplankton abundance, increase tenfold. Phytoplankton blooms bring about swarms of krill, which in turn attract blue whales. Blue whales are found in various locations off the southeast coast of Australia, but most predominantly in the Bonney Upwelling region, which is one of 12 identified blue whale feeding sites worldwide.
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In many numerical models and observational syntheses, the Southern Ocean upwelling represents the primary means by which deep dense water is brought to the surface. Shallower, wind-driven upwelling is also found off the west coasts of North and South America, northwest and southwest Africa, and southwest and southeast Australia, all associated with oceanic subtropical high pressure circulations. Some models of the ocean circulation suggest that broad-scale upwelling occurs in the tropics, as pressure driven flows converge water toward the low latitudes where it is diffusively warmed from above. The required diffusion coefficients, however, appear to be larger than are observed in the real ocean.
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Journal of Geophysical Research – Oceans, VOL. 115, C12071, 11 pp., Recently, a new upwelling centre has been discovered on the western shelf of Tasmania.Kämpf, J., 2015.
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A series of slump scarps along the western edge of the shelf are 18–2 Mya, but covered by younger sediments brought there by the Benguela upwelling.
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Coastal upwelling provides abundant nutrients which feeds krill, a type of marine crustacea, which in turn feeds a complex of living creatures from penguins to blue whales.
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Stratification may be upset by turbulence. This creates mixed layers of water. Forms of turbulence may include wind-sea surface friction, upwelling and downwelling. Marshall et al.
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C. pseudocurvisetus is a tropical or subtropical species. The most recent discoveries have been in warm waters off Japan’s coast, including upwelling regions around the Izu Islands.
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Double diffusion convection plays a significant role in upwelling of nutrients and vertical transport of heat and salt in oceans. Salt fingering contributes to vertical mixing in the oceans. Such mixing helps regulate the gradual overturning circulation of the ocean, which control the climate of the earth. Apart from playing an important role in controlling the climate, fingers are responsible for upwelling of nutrients which supports flora and fauna.
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Under this scenario, off-axis lithosphere is weakened by a hotspot near a spreading ridge. Upwelling of magma at the weakened off-axis lithosphere causes development of divergence. Dominance of upwelling at the new rift causes sharp decrease in spreading rate of the old spreading axis and sharp increase in spreading rate of the new rift. As the old spreading center ceases, the new rift forms the new spreading center.
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An oxygen minimum zone (OMZ) is characterized as an oxygen-deficient layer in the world oceans. Typically found between 200m to 1500m deep below regions of high productivity, such as the western coasts of continents. OMZs can be seasonal following the spring-summer upwelling season. Upwelling of nutrient- rich water leads to high productivity and labile organic matter, that is respired by heterotrophs as it sinks down the water column.
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Coastal zones provide nitrogen from runoff and upwelling occurs readily along the coast. However, the rate at which nitrogen can be taken up by phytoplankton is decreased in oligotrophic waters year- round and temperate water in the summer resulting in lower primary production. The distribution of the different forms of nitrogen varies throughout the oceans as well. Nitrate is depleted in near-surface water except in upwelling regions.
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The Columbia River estuary exports high rates of nutrients into the Pacific Ocean; with the exception of nitrogen, which is delivered into the estuary by ocean upwelling sources.
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Hall, J.A. and W.F. Vincent. Vertical and horizontal structure in the picoplankton communities of a coastal upwelling system. Marine Biology 106, 465-471 (1990). Accessed April 30, 2008.
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The Columbia River estuary exports high rates of nutrients into the Pacific Ocean; with the exception of nitrogen, which is delivered into the estuary by ocean upwelling sources.
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South Africa,Velimirov, B., J.G. Field, C.L. Griffiths and P. Zoutendyk. 1977. The ecology of kelp bed communities in the Benguela upwelling system. Helgoland Marine Research 30: 495-518.
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Around 2070 Ma an asthenospheric upwelling released a large volume of post-orogenic magmas. Eburnian trends within the Eglab shield were repeatedly reactivated from the Neoproterozoic to the Mesozoic.
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McGuire, AV, and RG Bohannon. “Timing of Mantle Upwelling: Evidence for a Passive Origin for the Red Sea Rift.” Journal of Geophysical Research: … 94.No. B2 (1989): 1677–1682.
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Thus, nutrient cycling and primary production in the estuary are heavily linked with the seasonal winds off the Oregon and Washington coasts that control local ocean upwelling and downwelling.
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It is difficult to precisely determine what causes large ultramafic – mafic intrusives to be emplaced within the crust, but there are two main hypotheses: plume magmatism and rift upwelling.
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Satellite observations of mesoscale eddy-induced Ekman pumping. Journal of Physical Oceanography, 45(1), 104-132. Upwelling and downwelling processes in the eddies create a cold and warm core.
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North Atlantic Deep Water is primarily upwelled at the southern end of the Atlantic transect, in the Southern Ocean. This upwelling comprises the majority of upwelling normally associated with AMOC, and links it with the global circulation. On a global scale, observations suggest 80% of deepwater upwells in the Southern Ocean.Talley, Lynne D. "Closure of the global overturning circulation through the Indian, Pacific, and Southern Oceans: Schematics and transports." Oceanography 26.1 (2013): 80–97.
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This may suggest that the Hirnantian-Rhuddanian anoxic event (and its corresponding extinction) began during the glaciation, not after it. Cool temperatures can lead to upwelling, cycling nutrients into productive surface waters via air and ocean cycles. Upwelling could instead be encouraged by increasing oceanic stratification through an input of freshwater from melting glaciers. This would be more reasonable if the anoxic event coincided with the end of glaciation, as supported by most other studies.
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Downwellings are common in Hecate Strait and Queen Charlotte Sound, especially in winter, but there is an occasional summer upwelling. These upwellings bring nutrient-rich waters to the sponge reefs.
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The site at Tagus Cove is species rich because of the upwelling of the nutrient-laden, cool water Equatorial Undercurrent nearby, providing an optimum environment for growth which may encourage gigantism.
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FluxNet, the neural network version of Streamer, calculates upwelling and downwelling surface flux in either shortwave or longwave. It is less flexible than Streamer but is two to four times faster.
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Upwelling is an oceanographic phenomenon that involves wind-driven motion of surface water away from the coast, which is replaced by a flow of deeper dense, cooler, and usually nutrient-rich water towards the ocean surface, The nutrient-rich upwelled water stimulates the growth and reproduction of primary producers such as phytoplankton. Due to the biomass of phytoplankton and presence of cool water in these regions, upwelling zones can be identified by cool sea surface temperatures (SST) and high concentrations of chlorophyll-a. The increased availability of nutrients in upwelling regions results in high levels of primary production. Upwellings that are driven by coastal currents or diverging open ocean have the greatest impact on nutrient-enriched waters and global fishery yields.
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Chlorophyll growth extending off the coast of Lake Nicaragua due to nutrient upwelling by January 2001 Papagayo Jet The Papagayo jet is an important meteorological phenomenon when considering ocean biodiversity in the eastern tropical Pacific. The jet plays a key role in lowering sea surface temperatures, through the influence on the Costa Rica Dome. The movement and growth of the dome is caused by the seasonal variability of the jet where the annual upwelling and mixing caused by the Papagayo jet during dome extension allows for the transport of nutrient-rich cold waters to the surface. If the jet was a permanent feature (and by extension, the dome was also permanent) there would be no seasonal transport of nutrients via cold water upwelling.
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MSU weighting functions based upon the U.S. Standard Atmosphere. From 1979 to 2005 the microwave sounding units (MSUs) and since 1998 the Advanced Microwave Sounding Units on NOAA polar orbiting weather satellites have measured the intensity of upwelling microwave radiation from atmospheric oxygen. The intensity is proportional to the temperature of broad vertical layers of the atmosphere. Upwelling radiance is measured at different frequencies; these different frequency bands sample a different weighted range of the atmosphere.
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Divergent fronts occur when the water masses on both sides of the front are moving away from the front and hence each other. At divergent fronts, the water is often cooler than in the surrounding area, and water moving away from the front leads to a slightly lower sea level. This causes decreased pressure on the water column, and leads to upwelling at the front. This upwelling can bring nutrients to the surface and lead to phytoplankton growth.
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This dense-water pool, named the Kangaroo Island Pool, drifts along the shelf bottom just offshore of Kangaroo Island and the Eyre Peninsula. When a classical wind-driven upwelling event occurs, normally two to three times a summer, cold water is upwelled from the pool, not directly from the ocean floor.McClatchie, S., J. F. Middleton, and T. M. Ward (2006), Water mass and alongshore variation in upwelling intensity in the eastern Great Australian Bight, J. Geophys. Res., 111, C08007, .
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Areas where bottom structure (islands, seamounts, banks, and the edge of the continental shelf) creates upwelling, which brings deep nutrient-rich water close to the surface, are particularly favoured by blue marlin.
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In more southern Indian waters such as those of Chennai, it occurs in greater numbers between January and April. It becomes abundant during times when there is an upwelling of deep water.
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Uranium decay- series disequilibria data has shown that the actively flowing region of the melt zone is km wide at its base and at the upper mantle upwelling, consistent with tomographic measurements.
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Modelers have hypothesized that due to environmental conditions anoxia and sulfide may have been brought up from a deep, vast euxinic reservoir in upwelling areas, but stable, gyre-like areas remained oxic.
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Point Conception SMR includes a major biogeographic boundary and is designed to protect key habitats including an upwelling zone, oil seeps, pinnacles, rocky reefs, kelp forest, deep rock, and harbor seal haulouts.
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Due to this the region of upwelling in the eastern equatorial Atlantic remains strong and the waters in the pelagic zone are cooler. The proof that this pattern of periodic weakening of the eastern equatorial Atlantic upwelling exists is found in deposits of surface dwelling planktic organisms in ocean sediment cores. Such cores show that the relative abundance of warm and cold water planktic species vary with a consistent beat of 23,000 years, matching the 23,000 year precession insolation cycle.
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In upwelling ecosystems, every species present plays a vital role in the functioning of that ecosystem. If one species is significantly depleted, that will have an effect throughout the rest of the trophic levels. For example, if a popular prey species is targeted by fisheries, fishermen may collect hundreds of thousands of individuals of this species just by casting their nets into the upwelling waters. As these fish are depleted, the food source for those who preyed on these fish is depleted.
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This seasonal behaviour of the Great Whirl affects the local coastal ocean flows and thus the Arabian Sea ecosystem: During the summer season, coastal upwelling currents strongly dependent on the shape and behaviour of the eddy are observed to the northwest of the Great Whirl. Not only does the biological productivity of the region depend on these upwelling currents, they (and thus, the Great Whirl itself) also play a large part in regulating the heat flux budget of the North Indian Ocean.
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This is due primarily to the extensive upwelling of colder sub-surface waters caused by the prevailing northwesterly winds acting through the Ekman Effect. The winds drive surface water to the right of the wind flow, that is offshore, which draws water up from below to replace it. The upwelling further cools the already cool California Current which runs north to south along coastal California and even much of coastal Baja California. This is the same mechanism which produces coastal California's characteristic fog.
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All these dense water masses sinking into the ocean basins displace the older deep water masses that were made less dense by ocean mixing. To maintain a balance, water must be rising elsewhere. However, because this thermohaline upwelling is so widespread and diffuse, its speeds are very slow even compared to the movement of the bottom water masses. It is therefore difficult to measure where upwelling occurs using current speeds, given all the other wind-driven processes going on in the surface ocean.
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Deep waters have their own chemical signature, formed from the breakdown of particulate matter falling into them over the course of their long journey at depth. A number of scientists have tried to use these tracers to infer where the upwelling occurs. Wallace Broecker, using box models, has asserted that the bulk of deep upwelling occurs in the North Pacific, using as evidence the high values of silicon found in these waters. Other investigators have not found such clear evidence.
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Benguela Current in the South Atlantic Gyre The Benguela Current is the broad, northward flowing ocean current that forms the eastern portion of the South Atlantic Ocean gyre. The current extends from roughly Cape Point in the south, to the position of the Angola-Benguela front in the north, at around 16°S. The current is driven by the prevailing south easterly trade winds. Inshore of the Benguela Current proper, the south easterly winds drive coastal upwelling, forming the Benguela Upwelling System.
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Even if all human-controlled nitrogen pollution sources > were stopped today, nitrate nitrogen pollution in the Floridan aquifer and > in our springs will take years to decades to reverse. The Mud Hole submarine discharge vent is a significant research site because its warm, mineral rich fresh water discharge provides a sustained, consistent site of deep-water upwelling in the Gulf of Mexico. The upwelling carries nutrients, mineral and fresh water to the sea surface. > Karst springs occur both onshore and offshore in Florida.
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Although permaculture derives its origin from agriculture, the same principles of the approach, especially the foundational ethics can also be applied to mariculture, particularly seaweed farming. An example is Marine Permaculture wherein artificial upwelling of cold, deep ocean water is induced. When attachment substrate is provided in association with such an upwelling, and kelp sporophytes are present, a kelp forest ecosystem can be established (kelp needs the cool temperatures and abundant dissolved macronutrients present in such an environment). Microalgae proliferate as well.
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The Somali Current flows to the south throughout (Northern) Winter (Dec-Feb), constrained to the region south of 10°N, until in March, southward flow recedes again to 4°N to be reversed in April. During the winter monsoon, after crossing the equator, the southward Somali Current comes into confluence with the northward EACC and thereafter flows to the East. Upwelling behavior: One of the unique characteristics of the Somali Current is the presence of strong coastal upwelling - the only major instance of this happening at a western ocean boundary. Following Ekman transport and with the southwest monsoon blowing parallel to the Somali coastline, the upwelling direction is to the offshore during the summer: The warm and salty Somali Current flows northward across the equator to turn to the East near Cape Guardafui.
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This hypothesis then assumes that a crustal spreading zone is also underpinned by a corresponding asthenospheric mantle spreading zone or upwelling of warmer material. The gap is created because instead of the old subducted plate continuing to sink, it quickly melts, allowing the asthenospheric upwelling zone to act directly on the underside of the overriding plate, heating it and causing it to spread apart. The fast melt is because the portion of the subducted plate nearest the spreading zone is thin and still warm from its recent creation. The slab gap hypothesis goes on to state that the upwelling can form very deep cracks, which in turn lets very fluid basalt lava quickly spread over the land surface forming shield volcanoes and vast volcanic plains called "flood basalts".
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The Cromwell Current is both oxygen- and nutrient-rich. A large number of fish are concentrated in it. Upwelling occurs near the Galapagos islands. This brings food supplies to the surface for Galápagos penguin.
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Tropical Cyclone Connie slowly strengthened, although this process was slowed due to upwelling of cold ocean waters. That morning, the JTWC upgraded Connie to a hurricane. At 0703 UTC, satellite imagery dedicated a wide eye.
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A model of formation due to mantle plumes (upwelling) was persistent for many years, however, it has since been abandoned due to its contradictory prediction of sequences of extension versus the observed cross cutting relationships.
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Elbrächter, M. 1979: On the taxonomy of unarmoured dinophytes (Dinophyta) from the Northwest African upwelling region. Meteor Forsch-Ergebn. 30: 1-22. Still others have found scarce pigmentation or green chloroplasts common between both species.
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Somalia has the longest coastline on mainland Africa,International Traffic Network, The world trade in sharks: a compendium of Traffic's regional studies, (Traffic International: 1996), p.25. and some of the continent's richest fish stocks. The abundance in fisheries in the area is a result of the coastal upwelling of cold nutrient-rich subsurface oceanic waters. The upwelling results in the enrichment of phytoplankton and zooplankton, which, in turn, make the conditions favorable for some small pelagic fish such as sardines, herring, and scad.
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The upper layer Somali Current flows northwards along the East African coast, and finally enters the Gulf of Aden between the Socotra Archipelago and the Horn of Africa. The mean flow velocity of this outgoing current is about 5 Sv. The period between August–September is the late phase of the summer monsoon. During this period, the Great Whirl almost forms a closed circulation, and strong upwelling streams (colder than 17 °C, typical upwelling water temperature ~ 19-23 °C) develop near the Northern Somali coast.
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Conversely, the fall transition from upwelling back to downwelling, and the resultant rise in sea level, is significantly more gradual. It is important to note that although upwelling and downwelling are generally seasonably favored, they can occur during either season since they driven by wind direction. As explored below, the topographic variations unique to Heceta Bank significantly influence how these wind-driven seasonal changes affect this region. This influence is largely because areas with a wider continental shelf respond less strongly to the wind-driven forces.
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Due to the Coriolis force acting to the left in the Southern Hemisphere and the resulting Ekman transport away from the centers of the gyre, these regions are very productive due to upwelling of cold, nutrient rich water. Strong upwelling in the gyre is shown where the deep-water isotherms curve upwards. The Weddell front, which is identical to the Southern Antarctic Circumpolar Current Front, separates the Weddell gyre from the Antarctic Circumpolar Current . The flow is cyclonic, although the cavity flow is anticyclonic.
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Brubaker J., Largier J., Shanks A.L., 2003. Observations on the Distribution of Meroplankton During an Upwelling Event. Journal of Plankton Research. Vo. 25, No 6, pp: 645-667 The distribution of meroplankton is also highly seasonal.
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Upwelling, however, is a sporadic phenomenon; it fails to occur on a regular basis, and so the food supply comes and goes. The penguins have several adaptations to cope with this, including versatility in their breeding habits.
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Additionally, upwelling from Hurricane Bonnie roughly a week earlier contributed to a decrease in strength. Although the storm weakened further, reconnaissance aircraft observations on August 29 concluded that the structure of Danielle had improved compared to the previous day. By early on August 30, Danielle had weakened to the extent that it was only a minimal hurricane, with maximum winds of 75 mph (120 km/h) at the time. On August 30, the National Hurricane Center noted that Danielle would soon leave the upwelling track left by Bonnie, and likely lead to intensification.
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This flow deflection causes strong upwelling along the Somali coast, lowering coastal temperatures by 5 °C or more from May through September. During the winter season, the northeast monsoon reverses the northward Somali Coastal Current, shutting down coastal upwelling. Somali Undercurrent: April – early June ; A southward undercurrent develops underneath the northward surface current (depth 100-300m, monthly average velocity 20 cm/s, maximum 60 cm/s), stretching to the near 4°N and turning offshore. It is eventually terminated by the establishment of the deep–reaching Great Whirl.
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Ocean temperature is related to ocean heat content, an important topic in the study of global warming. Coastal SSTs can cause offshore winds to generate upwelling, which can significantly cool or warm nearby landmasses, but shallower waters over a continental shelf are often warmer. Onshore winds can cause a considerable warm-up even in areas where upwelling is fairly constant, such as the northwest coast of South America. Its values are important within numerical weather prediction as the SST influences the atmosphere above, such as in the formation of sea breezes and sea fog.
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In the northern sector surface temperature varies a bit more (13 to 22°C) than in the south (14 to 20°C) during the year. Surface temperature variation from year to year is linked to the El Niño–Southern Oscillation. During El Niño years the South Atlantic high is shifted, reducing the south-easterly winds, so upwelling and evaporative cooling are reduced and sea surface temperatures throughout the bay are warmer, while in La Niña years there is more wind and upwelling and consequently lower temperatures. Surface water heating during El Niño increases vertical stratification.
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Schumann, E.H. (1987) The coastal ocean off the east coast of South Africa. Transactions of the Royal Society of South Africa 46, 215–229 In the field of physical oceanography, in the fine structure of coastal upwelling systems,Coastal Upwelling Ecosystems Analysis (January 1978) Vol 7 Bang—along with W.R.H (Bill) Andrews and Larry Hutchings, his counterparts in biological oceanography—produced work that was acclaimedGotthilf Hempel, Michael O’Toole and Neville Sweijd (editors)(2008). Benguela: Current of Plenty, A history of international cooperation in marine science and ecosystem management, Benguela Current Commission. p26. in their field.
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The bay's coastline and surrounding areas are part of the western Sahara Desert, being covered mostly by dunes, making Cintra bay's vegetation very poor. In contrast to the land, the waters in this area are part of the Canary Current System which is a highly productive ocean current, and the Nouadhibou Upwelling. One of major upwelling zones is located just off the continental shelf. This makes the area one of the richest grounds for fishing in the world, and Cintra Bay itself serves as a hotspot for zooplankton and a spawning ground for sardines.
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Huntsman and Barber (1977) hypothesized that high productivity results from alternating upwelling events and relatively calm periods. Upwelling is necessary to bring the nutrients to the surface but if the event is sustained for a long period of time, it is tough for phytoplankton to remain in the euphotic zone. Calm periods allow for stratification to develop, which means that phytoplankton can grow and multiply while held in the shallow mixed layer. In other words, there is a miniature spring bloom during each calm period (Mann & Lazier, 1996).
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On the western side of the sea the trade winds influence a northerly current which causes an upwelling and a rich fishery near Yucatán.Pernetta, John. (2004). Guide to the Oceans. Buffalo, NY: Firefly Books, Inc. pp. 177–178. .
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There are often summer upwelling events, during which water temperatures may drop to 11 °C. Although this area is included in the warm temperate Agulhas bioregion, it is part of the transition between warm and cool temperate regions.
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This caused diatoms to take in less silica for the formation of their frustules. Increased mixing of the oceans renews silica and other nutrients necessary for diatom growth in surface waters, especially in regions of coastal and oceanic upwelling.
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Just outside the bay, there is a large shoal area at Rocky Bank, and a large ridge extending south-west from Cape Hangklip, which channels cold, nutrient- rich water into the west side of the bay during upwelling events.
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Summer upwelling along the Oregon coast brings nutrients from deep waters up into the Yaquina Bay estuary. This event, along with decreased rain and river input, and increased light, all contribute to the seasonal chemistry variability in the Bay.
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Forage fish thrive in those inshore waters where high productivity results from the upwelling and shoreline run off of nutrients. Some are partial residents that spawn in streams, estuaries, and bays, but most complete their life cycle in the zone.
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Mediterranean Sea, Black Sea, Caspian Sea, Red Sea, Persian Gulf, deep water lakes/reservoirs are suitable for artificial upwelling for enhancing fish catch economically. These units can also be mobile type to utilise the seasonal favourable winds all around the year.
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The cool nutrient-rich waters of the north Pacific are able to provide kelp forests with millions of plankton – the base of the aquatic food chain – due to an upwelling of water from the deep sea in the stormy, winter months.
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Sc. Paris., 294, p.399-404 In radiolarian oozes deposited in the equatorial Eastern Atlantic 11.5 meters/million years have been measured. In upwelling areas like off the Peruvian coast extremely high values of 100 meters/million years were reported.
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There is also an increased upwelling of deep cold ocean waters and more intense uprising of surface air near South America, resulting in increasing numbers of drought occurrences, although fishermen reap benefits from the more nutrient-filled eastern Pacific waters.
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DOI: 10.1016/j.pocean.2008.10.012 This is highly uncharacteristic of tropical waters, as most other regions have temperatures measuring above . Upwelling brings nutrients to the surface, which support phytoplankton and ultimately increase biological productivity. The Humboldt Current is a highly productive ecosystem.
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DeVries, Tim, and François Primeau. "Dynamically and observationally constrained estimates of water-mass distributions and ages in the global ocean." Journal of Physical Oceanography 41.12 (2011): 2381–2401. Because of its low carbon concentration, this upwelling functions as a carbon sink.
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Ocean circulation is further driven by the interaction with wind. The salt component also influences the freezing point temperature. Vertical movements can bring up colder water to the surface in a process called upwelling, which cools down the air above.
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The possibility of such an ecosystem collapse is the very danger of fisheries in upwelling regions. Fisheries may target a variety of different species, and therefore they are a direct threat to many species in the ecosystem, however they pose the highest threat to the intermediate pelagic fish. Since these fish form the crux of the entire trophic process of upwelling ecosystems, they are highly represented throughout the ecosystem (even if there is only one species present). Unfortunately, these fish tend to be the most popular targets of fisheries as about 64 percent of their entire catch consists of pelagic fish.
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Upwelling current at the Somali coast during Southwest Monsoon The offshore Somali coastal area is one of the most productive marine ecosystems in the world. Especially during the southwest Indian monsoon, strong upwelling pumps cold (17-22 °C) and highly nutrient rich (about 5 to 20 μm of nitrate ) subsurface water to the coastal region. During this season, mean phytoplankton density and productivity is further boosted by the activities of the offshore eddy, the Great Whirl. Total zooplankton biomass consists of about 25% Euphausids, the rest being Copepods (dominant zooplankton species in the region ~ Calanoides carinatus and Eucalanus elongates).
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Because of the location of Zmudowski State Beach, in Moss Landing, coastal upwelling plays a large part on the beach in the spring and summer. Winds from the north, along the coast blow south past Monterey, causing the surface water to be pushed away, and the water from underneath to rise, or “upwell,” and replace the surface water with nutrient rich water. This is why Zmudowski State Beach is such a great place to fish—the water has high biological productivity. Upwelling has fluctuated significantly in the past two decades, effecting the fishing and wildlife at Zmudowski State Beach.
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Two species of Stylodictya, Stylodictya multispina and Stylodictya validispina, are quite prevalent in ecological literature regarding Radiolarian diversity. These two species are found quite commonly in the western Pacific, particularly extending from equatorial regions east of Java to south of New Zealand. Stylodictya multispina is also known to be found in the central equatorial Pacific and in the Gulf of Mexico, however the full distribution of the genus is not wholly understood. Based on data from the western Pacific correlating Stylodictya distribution with upwelling zones, the appearance of the genus is likely highly dependent on upwelling.
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Sea surface temperature anomalies are a physical indicator which adversely affect the zooplankton (mainly copepods) in the Northeast Pacific and specifically in the Coastal Upwelling Domain. Warm waters are much less nutrient-rich than the cold upwelling waters which were the norm till recently off the Pacific Coast. This results in reduced phytoplankton productivity with knock on effects on the zooplankton which feed on it and the higher levels of the food chain. Species lower in the food web that prefer colder waters, which tend to be fattier were replaced by warmer water species of lower nutritional value.
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The Chivela Pass is a narrow mountain pass in the Sierra Madre Mountains that funnels cooler, drier air from the North American continent, through southern Mexico, into the Pacific. These northeasterly winds, specifically the Tehuano wind, which periodically blows across the Isthmus of Tehuantepec in southern Mexico, and offshore over hundreds of miles of the Pacific Ocean, forcing the upwelling of colder subsurface waters. This strong upwelling brings nutrients from the subsurface layers of the ocean, thereby enhancing the fertility of the offshore waters. This results in strong plankton growth which in turn supports a more bountiful fishery in the region.
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The volcanism might have been mostly generated by asthenospheric upwelling possibly by displacement along the transform fault. If the transform fault had a section of vertical tearing to contain potentially different dip angles between the Explorer and Juan de Fuca Plates, the subducted plate asthenosphere may possibly flow upward into the mantle wedge. Similarly, if the displacement had a section of extension, a horizontal slab window-like gap would have developed, again allowing a pathway for upwelling magma. In either case, the unsettled asthenosphere might have experienced low degrees of decompressional melting and interacted with North American lithosphere to yield within plate compositions.
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Warm core rings are also detected by sea surface height anomalies. Since warm water takes up more space as it expands than cold water, the large amount of warm water causes an upwelling in sea height which can be detected by buoys.
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An American Stranger is the debut album from indie rock band The Upwelling, released on August 25, 2009. It was released after the band was signed to Edmond Records, owned by The All-American Rejects, in partnership with Doghouse Records and Warner Bros..
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As all fish, the black snake mackerel has a variety of parasites. A study performed on fish from the subtropical upwelling region off North-West-Africa indicated that they harbour Myxozoa, Digenea, Monogenea, Cestoda, Nematoda including two species of Anisakis, Acanthocephala, and Copepoda.
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Tropical cyclones mix the ocean water within a radius three times that of the RMW, which lowers sea surface temperatures due to upwelling. Much is still unknown about the radius of maximum wind in tropical cyclones, including whether or not it can be predictable.
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Journal of the Marine Biological Association of the United Kingdom. .. Retrieved on April 16, 2017Oviedo L.. Ecology of Neritic Odontocete Cetaceans in an Upwelling Ecosystem in the Northeast Coast of Venezuela: Delphinus Spp, Sotalia guianensis. The Rufford Foundation. Retrieved on April 16, 2017 and orcas.
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As well as acting as a heat pump and high-latitude heat sink,Morrison, Adele K., Thomas L. Frölicher, and Jorge L. Sarmiento. "Upwelling in the." Physics today 68.1 (2015): 27. AMOC is the largest carbon sink in the Northern Hemisphere, sequestering ∼0.7 PgC/year.
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Many continental rift zones are associated with magmatism due to upwelling of the asthenosphere as the lithosphere is thinned, which leads to decompression melting. The magmatism is often bimodal in character as the mantle-derived basaltic magmas cause partial melting of the continental crust.
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Volcanic plateaus are produced by volcanic activity. The Columbia Plateau in the north-western United States is an example. They may be formed by upwelling of volcanic magma or extrusion of lava. The Pajarito Plateau in New Mexico is an example of a volcanic plateau.
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Antarctic and common minke whales diverged from each other in the Southern Hemisphere 4.7 million years ago, during a prolonged period of global warming in the early Pliocene which disrupted the Antarctic Circumpolar Current and created local pockets of upwelling, facilitating speciation by fragmenting populations.
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Creating high pressure zones by artificial upwelling on sea area selectively can also be used to deflect / guide the normal monsoon global winds towards the landmass. Artificial upwelling of nutrient-rich deep ocean water to the surface also enhances fisheries growth in areas with tropical and temperate weather. It would also lead to enhanced carbon sequestration by the oceans from improved algae growth and mass gain by glaciers from the extra snow fall mitigating sea level rise or global warming process. Tropical cyclones also do not pass through the high pressure zones as they intensify by gaining energy from the warm surface waters of the sea.
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Heat waves can result in mass mortality episodes at nesting sites, as the penguins have poor physiological adaptations towards losing heat. Climate change is recognised as a threat, though currently it is assessed to be less significant than others. Efforts are being made to protect penguins in Australia from the likely future increased occurrence of extreme heat events. Variation in the timing of seasonal ocean upwelling events, such as the Bonney Upwelling, which provide abundant nutrients vital to the growth and reproduction of primary producers at the base of the food chain, may adversely affect prey availability, and the timing and success or failure of little penguin breeding seasons.
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Observed variations in the strength of the eastern equatorial Atlantic upwelling zone can also be used to support a cycle of the North African Monsoon that is regulated by the precession cycle. When insolation in North Africa is at its peak during the precession cycle the easterly trade winds over the equatorial Atlantic are strongly diverted toward the Sahara. This diversion weakens the equatorial upwelling zone in the eastern equatorial Atlantic, resulting in warmer waters in the pelagic. On the other end of the spectrum when insolation in North Africa is at a minimum due to the precession cycle, the diversion of the easterly trade winds is relatively weak.
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Upwelling at the equator is associated with the Intertropical Convergence Zone (ITCZ) which actually moves, and consequently, is often located just north or south of the equator. Easterly (westward) trade winds blow from the Northeast and Southeast and converge along the equator blowing West to form the ITCZ. Although there are no Coriolis forces present along the equator, upwelling still occurs just north and south of the equator. This results in a divergence, with denser, nutrient-rich water being upwelled from below, and results in the remarkable fact that the equatorial region in the Pacific can be detected from space as a broad line of high phytoplankton concentration.
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Monterey Bay, located in central California, experienced a toxic P. australis algal bloom in the spring of 2015 leading to detrimental ecological issues such as marine organism illness and mortality. This bloom was caused by an unusual prolonged period of oceanic warming and upwelling which created conditions that allowed for an explosion of the P. australis species. The increase of available nitrogen from upwelling allowed for an increase in domoic acid synthesis. This bloom event lead to the temporary closure of fisheries such as razor clam and crab fisheries up the west coast from California to Washington due to the harmful impacts of domoic acid on human health.
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Break-off of the subducting slab following the end of subduction would lead to the upwelling of hot asthenosphere, causing melting of the overlying lithosphere producing lamprophyric magmas, underplating and injecting into the crust. The granitic magmas may be a result of either partially melting the lamprophyric underplate or by differentiation from the lamprophyric magmas. Further upwelling would lead to an increase degree of melting within the crust, contributing to a decrease in the amount of mantle component in the granitic melts. This is consistent with an overall change from more basic to more acidic with time observed in the plutons and a reduction of Barium and Strontium.
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Portland today is the home of a varied professional fishing fleet of approximately 60 vessels, harvesting a wide variety of sustainable, commercial species. During the austral summer (November to May), the Bonney Upwelling (part of the larger Great South Australian Coastal Upwelling System) brings nutrient-rich deep ocean water to the surface in the Portland area, supporting a rich abundance of marine life. Trawlers target deepsea finfish such as rockling, hoki, blue eye trevalla and more, while Southern rock lobster, giant crab, blacklip and greenlip abalone, arrow squid, wrasse and others are also landed in significant quantities.Butler, A. J., F. Althaus, D. M. Furlani, and K. R. Ridgway.
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Nils Bang on board HMS Hecla on 15 February 1966, during a Benguela Current research cruiseNils Daniel Bang (13 September 1941 – 2 December 1977) was a South African oceanographic scientist who was a pioneerGotthilf Hempel, Michael O’Toole and Neville Sweijd (editors)(2008). Benguela: Current of Plenty, A history of international cooperation in marine science and ecosystem management, Benguela Current Commission. p26. in the study of the fine structure of coastal upwelling systems.Coastal Upwelling Ecosystems Analysis (January 1978) Vol 7 In March 1969, Bang initiated, planned and executed South Africa's first truly multi-ship oceanographical research operation,South African Journal of Science (January 1978) Vol 74.
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Other classifications of marine ecoregions or equivalent areas have been widely developed at national and regional levels, as well as a small number of global schemes. Each of these systems, along with numerous regional biogeographic classifications, was used to inform the MEOW system. The WWF Global 200 work also identifies a number of major habitat types that correspond to the terrestrial biomes: polar, temperate shelves and seas, temperate upwelling, tropical upwelling, tropical coral, pelagic (trades and westerlies), abyssal, and hadal (ocean trench). ;Briggs Coastal Provinces One of the most comprehensive early classifications was the system of 53 coastal provinces developed by Briggs in 1974.
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Continental margin upwelling areas, such as the Gulf of California, the Peru and Chile coast, are characteristic for some of the highest biogenic silica accumulation rates in the world. For example, biogenic silica accumulation rates of 69 g SiO2/cm2/kyr have been reported for the Gulf of California. Due to the laterally confined character of these rapid biogenic silica accumulation zones, upwelling areas solely account for approximately 5% of the dissolved silica supplied to the oceans. At last, extremely low biogenic silica accumulation rates have been observed in the extensive deep- sea deposits of the Atlantic, Indian and Pacific Oceans, rendering these oceans insignificant for the global marine silica budget.
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Oceanic oxygen minimum zones generally occur in the middle depths of the ocean, from 100 – 1000 m deep, and are natural phenomena that result from respiration of sinking organic material produced in the surface ocean. However, as the oxygen content of the ocean decreases, oxygen minimum zones are expanding both vertically and horizontally. As low oxygen zones expand vertically nearer to the surface, they can affect coastal upwelling systems such as the California Current on the coast of Oregon (US). These upwelling systems are driven by seasonal winds that force the surface waters near the coast to move offshore, which pulls deeper water up along the continental shelf.
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For example, the average July SST (sea surface temperature) at New York City at 40.7°N is , while at the same latitude in Eureka, CA is . As such, ocean surf temperatures are rarely above during the summer along the California coast south to San Diego, while they are often above on the east coast from North Carolina southward. The cold water is highly productive due to the upwelling, which brings to the surface nutrient- rich sediments, supporting large populations of whales, seabirds and important fisheries. Winds of the appropriate direction and strength to induce upwelling are more prevalent in the presence of Eastern boundary currents, such as the California Current.
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Benguela upwelling, in the Mediterranean Sea,Elshanawany, R., Zonneveld, K.A.F., Ibrahim, M.I. and Kholeif, S.E.A. (2010). Distribution patterns of recent organic-walled dinoflagellate cysts in relation to environmental parameters in the Mediterranean Sea. Palynology Caspian Sea, British Columbia, The Northeastern Pacific, Florida, Mexico and Barends Sea.
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This region is largely bypassed by the Agulhas current, and has cooler inshore water due to upwelling, making it less hospitable to tropical Indo-west Pacific species. It is also isolated from the South Atlantic and Southern Ocean, so has been more prone to niche speciation.
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This region is largely bypassed by the Agulhas current, and has cooler inshore water due to upwelling, making it less hospitable to tropical Indo-west Pacific species. It is also isolated from the South Atlantic and Southern Ocean, so has been more prone to niche speciation.
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Where the obliquity of the SWIR increases so does its length. This lengthening results in a decrease in mantle upwelling and a ridge geometry characteristic of ultra-slow spreading ridges (<12 mm/yr). The orthogonal supersegment is similar to larger ridge segments of the Mid- Atlantic Ridge.
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Each year 2×1011 kg of CO2 is transferred from the crust to the mantle by subduction. (1700 tons of carbon per second). Upwelling mantle material can add to the crust at mid oceanic ridges. Fluids can extract carbon from the mantle and erupt in volcanoes.
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The two most important factors for the existence of Iceland, rifting in combination with a hot spot, an upwelling of unusual quantities of magma from the mantle, were also responsible for the existence of Reykjanesskagi.Thor Thordarson, Armann Hoskuldsson: Iceland. Classic geology of Europe 3. Harpenden 2002, p.
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Estuarine water circulation is controlled by the inflow of rivers, the tides, rainfall and evaporation, the wind, and other oceanic events such as an upwelling, an eddy, and storms. Estuarine water circulation patterns are influenced by vertical mixing and stratification, and can affect residence time and exposure time.
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They forage in offshore waters, eating fish and squid. No feeding patterns are known, although they are thought to forage in an ocean upwelling off Java, northwest of Christmas Island. Chicks are fed through complete regurgitation for the first two weeks, then incomplete regurgitation. Both parents feed the young.
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The Jet Propulsion Laboratory proposed to design and develop the AVIRIS in 1983. AVIRIS first measured spectral images in 1987 and measured the solar reflected spectrum from 400 nanometers to 2500 nanometers. AVIRIS measures upwelling radiance through 224 contiguous spectral channels at 10 nanometer intervals across the spectrum.
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On the shelf, methane transport is driven by upwelling where enrichment is observed. No significant amount of methane is released to the atmosphere from Heceta Bank alone, but the emission of methane from the seafloor to the atmosphere, worldwide, accounts for 4–9 % of the global methane budget.
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Based on the observations, the Hurricane Research Division estimated maximum sustained winds of 140 mph (220 km/h), making Connie a Category 4 hurricane. The hurricane progressed northwestward, passing northeast of The Bahamas. The eye grew in size, and the combination of upwelling and cooler air resulted in weakening.
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Due to global warming and increased glacier melt, thermohaline circulation patterns may be altered by increasing amounts of freshwater released into oceans and, therefore, changing ocean salinity. Thermohaline circulation is responsible for bringing up cold, nutrient-rich water from the depths of the ocean, a process known as upwelling.
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However, prediction models showed conflicting forecasts, and Cimaron remained quasi-stationary and weakened to a severe tropical storm on November 2. Dry air entrainment caused further weakening, with the JTWC dropping it to a minimal tropical storm at 3 p.m. UTC the next day. It weakened further, upwelling itself.
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In the fall of 1999, Tropical Storm Floyd further degraded the stream channel. Rapid incision of the channel, creating a constant upwelling of highly turbid groundwater. The turbid condition continued through low and high flows, with the stream remaining turbid from the project site to the Esopus Creek.
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Whereas in the cyclonic eddy, the upwelling entrains deep cold water and forms a cold-core. Previous studies show the deepening effects of MLD under anticyclonic eddies and shoaling of MLD in cyclonic eddies.Klein, P., Treguier, A. M., & Hua, B. L. (1998). Three-dimensional stirring of thermohaline fronts.
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Port Lincoln has a contrasting coastal landscape, ranging from sheltered waters and beaches, to surf beaches and rugged oceanic coastline. The Great South Australian Coastal Upwelling System brings cold, nutrient-rich water into nearby waters of the Great Australian Bight and Spencer Gulf. These upwellings support lucrative fisheries, including that of the southern bluefin tuna and sardine.Ward, T. M., McLeay, L. J., Dimmlich, W. F., Rogers, P. J., McClatchie, S., Matthews, R., Kämpf, J. and Van Ruth, P. D. (2006), Pelagic ecology of a northern boundary current system: effects of upwelling on the production and distribution of sardine (Sardinops sagax), anchovy (Engraulis australis) and southern bluefin tuna (Thunnus maccoyii) in the Great Australian Bight.
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A major finding of the flyby, announced on March 5, 2003, was of Jupiter's atmospheric circulation. Dark belts alternate with light zones in the atmosphere, and the zones, with their pale clouds, had previously been considered by scientists to be areas of upwelling air, partly because on Earth clouds tend to be formed by rising air. Analysis of Cassini imagery showed that the dark belts contain individual storm cells of upwelling bright-white clouds, too small to see from Earth. Anthony Del Genio of NASA's Goddard Institute for Space Studies said that "the belts must be the areas of net-rising atmospheric motion on Jupiter, [so] the net motion in the zones has to be sinking".
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The bathymetry of Heceta Bank causes the upwelling jet to move further offshore as it follows the bottom contours around the bank until it reaches the southern edge at the 200-m isobath. Here, approximately 0.5 Sverdrup of the cold upwelled water is exported out into the deep ocean as the jet cannot follow the continental shelf's abrupt turn back towards the coastline. The amount of materials lost into the deep ocean depends on the velocity of the jet, which is largely determined by the strength of the wind-driven currents. The movement of the upwelling jet around the seaward face of Heceta Bank causes the inshore side of the bank to have a significantly weaker flow.
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Drivers of hypoxia and ocean acidification intensification in upwelling shelf systems. Equatorward winds drive the upwelling of low dissolved oxygen (DO), high nutrient, and high dissolved inorganic carbon (DIC) water from above the oxygen minimum zone. Cross-shelf gradients in productivity and bottom water residence times drive the strength of DO (DIC) decrease (increase) as water transits across a productive continental shelf.Chan, F., Barth, J.A., Kroeker, K.J., Lubchenco, J. and Menge, B.A. (2019) "The dynamics and impact of ocean acidification and hypoxia". Oceanography, 32(3): 62–71. . 50px Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.Gewin, V. (2010) "Oceanography: Dead in the water". Nature, 466(7308): 812. .
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For many months he participated in the field work from the HUGH M. SMITH, and for more and harder months he carried out the analysis of the observations. As a result of this pioneering work, the knowledge of the physical and biological structure of the equatorial Pacific Ocean has been vastly advanced. These achievements are the more remarkable when one notes that comparable surveys of the equatorial Atlantic and Indian oceans are still lacking. Cromwell confirmed the existence of upwelling at the equator, disproved the existence of upwelling at the northern edge of the Equatorial Countercurrent, and originated a reasonable model of wind-induced current transport in the equatorial zone Cromwell, Townsend (1953).
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Upwelling is also influenced by factors such as the topography of the local ocean bottom and coastlines, the climate, and wind patterns. Overall, the mixing of deep and surface waters takes far longer than the mixing of atmospheric with the surface waters, and as a result water from some deep ocean areas has an apparent radiocarbon age of several thousand years. Upwelling mixes this "old" water with the surface water, giving the surface water an apparent age of about several hundred years (after correcting for fractionation). This effect is not uniform – the average effect is about 400 years, but there are local deviations of several hundred years for areas that are geographically close to each other.
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Theoretically, LC size increases with the wind speed unless limited by density discontinuities by pycnocline. But the visibility of surface effects of LC could be limited by the breaking waves during strong winds that disperse the materials present at the surface. So, the surface effects of LC are more likely to be visible during winds stronger than critical wind speed of 3 m/s but not too strong. PIV vectors of counter rotating vorticesMoreover, previous studies have shown that organisms and materials can aggregate at different regions within LC like downwelling current in convergent zone, upwelling current in divergent zone, retention zone in LC vortex and region between upwelling and downwelling zones.
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2, New York. John Wiley and Sons, lll5pp. A more detailed model was later developed by Stavn describing the zooplankton aggregation where the animal orientation, dorsal light reaction and current velocity determined their region of concentration in either downwelling (due to slow current), upwelling (due to high current) and in between latter two zones (due to intermediate currents). There has been further improvement in such models like the modification of Stommel's model by Titman & Kilham in order to consider the difference in maximum downwelling and upwelling velocities and by Evans & Taylor that discussed the instability of Stommel's regions due to varying swimming speed with depth which produced spiral trajectories affecting accumulation region.
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Location of the Ganiki Planitia Quadrangle Ganis Chasma is located in the Ganiki Planitia Quadrangle. This quadrangle is positioned between two volcanic regions on Venus. To the north lies the Atlanta Planitia lowland which was formed as the result of mantle upwelling and downwelling. To the south lies Alta Regio.
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Anchoveta are found in more recently upwelled waters, close to the coast. Sardines, on the other hand, are typically found farther offshore. Seasonal upwelling plays a major role in the spawning behaviors of both sardines and anchoveta. By spawning at the end of winter, egg and larval survival is greatly enhanced.
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Other factors, like rotation, vertical upwelling and magnetic fields might play a role as well. Previously one suggested scenario were thinner clouds. This brown dwarf shows variations in the J-band and at mid-infrared wavelengths with a period of 3.2 ± 0.3 hours. This is a clear indication of patchy clouds.
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Its distribution is also limited to areas with high biological productivity, such as the polar oceans, and upwelling zones near the equator. The least common type of sediment, it covers only 15% of the ocean floor. It accumulates at a slower rate than calcareous ooze: 0.2–1 cm/1000 yr.
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Emiliania huxleyi is considered a ubiquitous species. It exhibits one of the largest temperature ranges (1-30 °C) of any coccolithophores species. It has been observed under a range of nutrient levels from oligotrophic (subtropical gyres) to eutrophic waters (upwelling zones/ Norwegian fjords).Winter, A., Jordan, R.W. & Roth, P.H., 1994.
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The work is opened by a Sinfonia similar to the one of the cantata , possibly the slow movement of a concerto for oboe and violin. A sighing motif, the picture of a storm of tears, and the flood image conjured by the upwelling music characterizes the dark and oppressive feeling.
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Rob Lewis is a South Australian marine scientist and retired senior civil servant. He discovered the first known upwelling system in southern Australia and was professionally involved in fisheries and aquaculture management for 38 years. He was head of South Australian Research and Development Institute (SARDI) from 1992 to 2010.
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On the following day, Trami slowed and drifted northward. It began to weaken due to upwelling. Trami accelerated and turned northeastward on September 29, before it struck Japan on the next day, and became extratropical on October 1. The extratropical remnants persisted for days until dissipated completely on October 8.
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Dry air, westerly wind shear, and upwelling of cold waters prevented further intensification over the next 24 hours. Instead, Debby weakened, and by late on June 26, it was a minimal tropical storm. At 2100 UTC, the storm made landfall near Steinhatchee, Florida with winds of 40 mph (65 km/h).
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After entering the extreme southwestern Caribbean Sea, Joan strengthened into a hurricane. It then slowly executed a small counterclockwise loop, possibly in response to the nearby Tropical Depression Eighteen.Dr. Harold P. Gerrish. NHC Joan report p. 2 accessed April 10, 2006 Upwelling caused by the quasi-stationary hurricane weakened the system.
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This region is a major volcanic rise and was formed as the result of mantle upwelling. The Ganiki Planitia Quadrangle was strongly influenced by mantle flow tectonics derived from these two regions. The area contains many volcanic, tectonic, and impact features. Ganis Chasma is one of the extensional features located in the region.
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Cambridge U. Press, 2004, , p. 162 During Hadrian's third and last trip to the Greek East, there seems to have been an upwelling of religious fervour, focused on Hadrian himself. He was given personal cult as a deity, monuments and civic homage, according to the religious syncretism at the time.Marcel Le Glay.
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Mid-ocean ridge spreading centres are the sites of almost continuous magmatism. The basalts erupted at mid-ocean ridges are tholeiitic in character and result from the partial melting of upwelling asthenosphere. The composition of Mid-Ocean Ridge Basalts (MORB) shows little variation globally as they come from a mostly homogeneous source.
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The island is an important nesting site for green turtles as well as seabirds. Introduced house mice are present. It is surrounded by extensive coral reefs. The waters around the island are a site of upwelling associated with concentrations of tropical krill, and there have been unconfirmed reports of humpback whales feeding there.
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Low O2 conditions are attributed to the onshore movement of low O2, high-nutrient bottom water combined with respiration that followed upwelling-fueled, higher-than-average primary production in surface waters. In addition to increased primary production, respiration can further exacerbate O2 deficits as bottom boundary water transits shoreward over the shelf.
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Satellite imagery of low temperature and high (Chl-a) concentrations in the bank suggest that upwelling and productivity are enhanced in Heceta Bank in comparison to the surrounding shelf. In July 2003, high (Chl-a) values of 43 mg/L were directly sampled from an inshore shelf station on the Heceta Head line.
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MBio, 10(2): e01189-18. . 50px Material was copied from this source, which is available under a Creative Commons Attribution 4.0 International License.Gutierrez MH, Jara AM, Pantoja S (2016) "Fungal parasites infect marine diatoms in the upwelling ecosystem of the Humboldt current system off central Chile". Environ Microbiol, 18(5): 1646–1653. .
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Mode waters have a big impact on nutrients distribution as they prevent deep-ocean nutrients from upwelling to the euphotic zone. Further more, they will control the biological pump, which plays an important role in carbon dioxide uptake. Dynamically, mode waters also control potential vorticity and baroclinic in the subtropical North Atlantic.
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An upwelling of warmer water in this polynya helps keep it partially ice-free throughout the year, even when the ocean directly north and south is frozen. Another arm of the West Greenland Current reaches into Lancaster Sound, delivering Atlantic waters into the Arctic Ocean and contributing to that area's rich ecology.
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More nitrogen than carbon is remineralized from sinking organic material. Upwelling of this water allows more carbon to sink than that in the upwelled water, which would make room for at least some atmospheric CO2 to be absorbed. the magnitude of this difference is unclear. No comprehensive studies have yet resolved this question.
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The upwelling cloud eventually reaches the dry easterly air streams and dissipates, leading to a clear sky by 5pm. There is another maxima of temperature associated with this. Being an equatorial mountain the day light hours are constant with twelve hour days. Sunrise is about 0530 with the sun setting at 1730.
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Natural causes include coastal upwelling and changes in wind and water circulation patterns. Use of chemical fertilizers is considered the major human-related cause of dead zones around the world. Runoff from sewage, urban land use, and fertilizers can also contribute to eutrophication.Corn boom could expand 'dead zone' in Gulf NBC News.msn.
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Oceanic core complex structures form at slow spreading oceanic plate boundaries which have a limited supply of upwelling magma. These zones have low upper mantle temperatures and long transform faults develop. Rift valleys do not develop along the expansion axes of slow spreading boundaries. Expansion takes place along low-angle detachment faults.
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Point Dume SMCA and Point Dume SMR are located in an area that encompasses some of the most diverse habitats in Los Angeles County, including an upwelling zone, submarine canyon habitat, unique spur and groove reef structures, extensive kelp, and diverse understory algal habitat. This is an area of high species diversity.
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It is also one of five major coastal currents affiliated with strong upwelling zones, the others being the Humboldt Current, the Canary Current, the Benguela Current, and the Somali Current. The California Current is part of the North Pacific Gyre, a large swirling current that occupies the northern basin of the Pacific.
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The majority of these eddies were cyclonic and had the ability to induce the upwelling of nutrient- rich water. Small scale topographic features such as headlands have been shown to cause substantial effects on the population dynamics of benthic invertebrates, such a change in the settlement patterns of crabs and sea urchin.
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There are thousands of seamounts that are not clearly associated with upwelling mantle plumes, and there are chains of seamounts that are not age progressive. Seamounts that are not clearly linked to a mantle plume indicate that regional mantle composition and tectonic activity may also play important roles in producing intraplate volcanism.
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There has been considerable discussion as to how mariculture of seaweeds can be conducted in the open ocean as a means to regenerate decimated fish populations by providing both habitat and the basis of a trophic pyramid for marine life. It has been proposed that natural seaweed ecosystems can be replicated in the open ocean by creating the conditions for their growth through artificial upwelling and through submerged tubing that provide substrate. Proponents and permaculture experts recognise that such approaches correspond to the core principles of permaculture and thereby constitute Marine Permaculture. The concept envisions using artificial upwelling and floating, submerged platforms as substrate to replicate natural seaweed ecosystems that provide habitat and the basis of a trophic pyramid for marine life.
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Due to the Coriolis effect the surface water moves 90° to the left (in the South Hemisphere, as it travels toward the equator) of the wind current, therefore causing the water to diverge from the coast boundary, leading to Ekman suction. Additionally, there are areas of upwelling as a consequence of Ekman suction where the Polar Easterlies winds meet the Westerlies in the subpolar regions north of the subtropics, as well as were the Northeast Trade Winds meet the Southeast Trade Winds along the Equator. Similarly, due to the Coriolis effect the surface water moves 90° to the left (in the South Hemisphere) of the wind currents, and the surface water diverges along these boundaries, resulting in upwelling in order to conserve mass.
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It has been suggested that the Colorado Plateau acts as a semi-independent microplate and one way of explaining the creation of the Rio Grande rift is by the simple rotation of the Colorado Plateau 1-1.5 degrees in a clockwise direction relative to the North American craton. Other explanations that have been offered are that that extension is driven by mantle forces, such as large-scale mantle upwelling or small-scale mantle convection at the edge of the stable craton; collapse of over-thickened continental crust; initiation of transform faulting along the western margin of the North American plate; or detachment of a fragment of the Farallon plate beneath the Rio Grande region that enhanced asthenospheric upwelling in the slab window.
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They proposed that changes in air circulation patterns have led to increased upwelling of warm, deep ocean water along the coast of Antarctica and that this warm water has increased melting of floating ice shelves at the edge of the ice sheet. An ocean model has shown how changes in winds can help channel the water along deep troughs on the sea floor, toward the ice shelves of outlet glaciers. The exact cause of the changes in circulation patterns is not known and they may be due to natural variability. However, this connection between the atmosphere and upwelling of deep ocean water provides a mechanism by which human induced climate changes could cause an accelerated loss of ice from the WAIS.
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Pilskaln et al., 2005 However, Pilskaln et al. found that in the NPSG, marine snow was at a higher abundance than expected and were surprisingly comparable to a deep coastal upwelling system. Higher nutrient value may be because of Rhizosolenia mats, which also play an important role in contributing to marine snow in subtropical gyres.
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The high winds destroyed large areas of sugar and soybean crops, estimated at $289 million in damage. Strong winds also left at least 230,000 people without electricity. During the storm's passage, upwelling occurred in the Atchafalaya Basin and Bayou Lafourche, killing 187 million freshwater fish. Damage to the fishing industry was estimated at $266 million.
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Again, Ekman transport will push this water to the left of the surface motion, meaning away from Antarctica. Because water just offshore of Antarctica is being pushed away and into Antarctica, it leads to the Antarctic Divergence region. Here, upwelling of North Atlantic Deep Water (NADW) takes place. NADW is cold and quite saline.
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This finding was counter to earlier studies that placed the beginning of ice expansion in Antarctica at the start of the Oligocene roughly 34 million years ago. Carbon cycling in high-latitude oceans. In a study of Holocene marine sediments in the western Pacific Shevenell found evidence for increased upwelling in the North Pacific.
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Turbidity plume one km in diameter. Well before official discovery the Mud Hole Spring site was well known to local fishermen as a gathering place for marine life and activity. Local fishermen gave the name "mud hole" Upwelling phenomena may contribute to Red Tide plankton bloom events, which occur in this area. > Fanning et al.
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Julong Hot Springs below the falls create pools full of colorful algae that thrive in the geothermal water upwelling. This contributes headwater flow to the young Songhua river. The Songhua flows northward into the Amur, forming China's border with Russia, and eventually into the Sea of Okhotsk facing Sakhalin Island and the northern Pacific.
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Actinoscyphia aurelia This sea anemone is found in muddy situations at bathyal depths in deep water canyons in the Gulf of Mexico. It has also been observed at several sites in the upwelling region off the coast of West Africa as well as the American Samoan region of the Pacific, but is uncommon elsewhere.
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Furthermore, it revealed significant upwelling of at least 3 °C (5 °F) which served to limit Matthew's strength. Some intensification took place after the hurricane cleared the region of cooler water, and late on October 3, the hurricane reached its minimum central pressure of . The core had enlarged slightly by this time, with an estimated radius of maximum winds.
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Fish will likely be victim to extensive changes in distribution. Many species, such as salmon, cannot live in water over 21 °C. In addition to direct effects of temperature, increased volume and changed timing of stream flows are likely to cause many river-spawned eggs to wash downstream. Another significant factor is the timing of spring upwelling.
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Due to upwelling after moving slowly over the same waters, Hansella weakened quickly and passed about south of Rodrigues as a minimal tropical storm. On April 9, the storm passed just south of Mauritius, and the next day spawned a large area of convection over Réunion, dropping heavy rainfall. On April 10, Hansella dissipated just northwest of Réunion.
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Due to the upwelling zones within the Humboldt current, biological diversity is extremely high. The Humboldt Current is considered a Class I, highly productive (>300 gC/m2/yr) ecosystem. The current hosts a wide range of organisms including multiple species of plankton, mollusks, sea urchins, crustaceans, fish, and marine mammals. The food web starts with the phytoplankton.
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Scientists believe that this period of high biosiliceous productivity is linked to global climatic changes. This boom in siliceous plankton was greatest during the first one million years of the Tertiary period and is thought to have been fueled by enhanced upwelling in response to a cooling climate and increased nutrient cycling due to a change in sea level.
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Kakaban island is part of the Derawan Islands, East Kalimantan, Indonesia.Govt promotes new diving paradise in Aceh and Kalimantan The island has an area of and is quite steep. Its limestone cliffs are covered with dense jungle right down to the water's edge. The wall drops to , and currents can be strong with upwelling, downcurrent and reversing directions.
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The lower temperature is probably caused by the upwelling of the air in them and by the resulting adiabatic cooling. Such an interpretation is supported by the denser and higher clouds in the collars. The clouds lie at 70–72 km altitude in the collars—about 5 km higher than at the poles and low latitudes.
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The underlining mechanism in forming plateaus from upwelling starts when magma rises from the mantle, causing the ground to swell upward. In this way, large, flat areas of rock are uplifted to form a plateau. For plateaus formed by extrusion, the rock is built up from lava spreading outward from cracks and weak areas in the crust.
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In: Quarterly Journal of the Royal Meteorological Society. Band 129, Nr. 590, 2003, S. 1491-1511. The wind is strengthened locally by thermal but also orographic influences, as, for instance, by mountain ranges. The wind often leads in the coastal area to coastal upwelling of cool water, which, in turn often leads to a strengthening of the wind.
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Marine biologist Peter Gill estimates that 100 blue whales visit the Bonney Upwelling area every year, ranging over of ocean from Robe, South Australia to Cape Otway in Victoria. The feeding grounds may extend further northwest, encompassing the rest of the GSACUS, but incomplete whale surveys are insufficient to establish their true range.Clevers, Jeni. Producer's Diary. ‘’The Big Blue’’.
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What initiated rifting is unknown. suggested that as the continent overrode the Yellowstone hotspot, the upwelling plume tore away a previously accreted terrane. suggested a change in the rate at which the plates were converging, or the "kinematic effects" (such as a slab window) from the passage of the Kula-Farallon ridge (or Resurrection-Farallon ridge)..
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Other major sources of iron to the ocean include glacial particulates, atmospheric dust transport, and hydrothermal vents. Iron supply is an important factor affecting growth of phytoplankton, the base of marine food web. Offshore regions rely on atmospheric dust deposition and upwelling. Other major sources of iron to the ocean include glacial particulates, hydrothermal vents, and volcanic ash.
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Deep ocean currents are driven by density and temperature gradients. This thermohaline circulation is also known as the ocean's conveyor belt. These currents, sometimes called submarine rivers, flow deep below the surface of the ocean and are hidden from immediate detection. Where significant vertical movement of ocean currents is observed, this is known as upwelling and downwelling.
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The upwelling cloud eventually reaches the dry easterly air streams and dissipates, leading to a clear sky by 5 pm. There is another maximum of temperature associated with this. Being an equatorial mountain the daylight hours are constant with twelve-hour days. Sunrise is about 0630 with the sun setting at 1830 (both EAT = UTC+3).
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It is not a uniform wind-driven upwelling system, but is driven by various factors. While at Cape Comorin it can be modeled as just wind-driven, as the phenomena rises along the west coast of India, longshore wind stresses play an increasing role, as do atmospheric effects from the Bay of Bengal, such as Kelvin and Rossby waves.
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The Mud Hole Spring was first discovered by researchers in 1979 by using satellite imaging and analysis techniques. Discovery was made by analyzing data from a Nasa aircraft reconnaissance overflight in 1966 using infrared sensor technology. Data analysis revealed a sea surface temperature anomaly, suggesting the upwelling of thermally heated groundwater. 63 feet below sea level.
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It is considered to be of regional importance for its invertebrate population, including 33 species of water-beetle. The site also provides a habitat for nationally rare Least Minor moth, Photedes captiuncula. The wet areas of the site are relatively new, arising out of upwelling water from circa 1966 onwards, and so exhibit early stages of vegetative colonisation.
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Cutting through both Tartarus Dorsa and Pluto's heavily- cratered northern terrain (and thus formed more recently than both) is a set of six canyons radiating from a single point; the longest, informally named Sleipnir Fossa, is over 580 kilometers long. These chasms are thought to have originated from pressures caused by material upwelling at the center of the formation.
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The regime shift in the northern Benguela upwelling ecosystem is considered an example of ecosystem collapse in open marine environments. Prior to the 1970s sardines were the dominant vertebrate consumers, but overfishing and two adverse climatic events (Benguela Niño in 1974 and 1984) lead to an impoverished ecosystem state with high biomass of jellyfish and pelagic goby.
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The C. colorata is primarily preyed upon by leatherback turtles that inhabit the area. They are selected as prey due to the high concentrations of carbon and nitrogen in their four oral arms. They are particularly nutrient-dense during the post-upwelling season, which is when the leatherback concentration in the area is at its highest.
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Phosphorus is generally a limiting nutrient in the ocean. In Pacific Northwest estuaries, an important source of phosphorus comes from ocean upwelling in the summer (see below). Samples taken at the surface with varying salinities showed dissolved inorganic phosphorus more prevalent in areas with higher salinities compared to lower, thus indicating the ocean as the source for this system.
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MSU weighting functions based upon the U.S. Standard Atmosphere. Upwelling radiance is measured at different frequencies; these different frequency bands sample a different weighted range of the atmosphere. Since the atmosphere is partially but not completely opaque, the brightness measured is an average across a band of atmosphere, depending on the penetration depth of the microwaves.Dudhia, A. (2015).
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The effects of other submarine volcanoes along the Pacific Northwest, including Cobb Seamount off the coast of Washington, affect the composition and abundance of plankton up to away from the seamount summit due to the upwelling of nutrients from deeper waters. Because of its similar size, Bowie Seamount most likely has a similar effect on its adjacent waters.
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Floating wind turbines can be used to provide motive power for achieving artificial upwelling of nutrient-rich deep ocean water to the surface for enhancing fisheries growth in areas with tropical and temperate weather. Though deep seawater (below 50 metres depth) is rich in nutrients such as nitrogen and phosphorus, the phytoplankton growth is poor due to the absence of sunlight. The most productive ocean fishing grounds are located in cold water seas at high latitudes where natural upwelling of deep sea water occurs due to inverse thermocline temperatures. The electricity generated by the floating wind turbine would be used to drive high–flow and low–head water pumps to draw cold water from below 50 meters water depth and mixed with warm surface water by eductors before releasing into the sea.
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The stratosphere is a region of intense interactions among radiative, dynamical, and chemical processes, in which the horizontal mixing of gaseous components proceeds much more rapidly than does vertical mixing. The overall circulation of the stratosphere is termed as Brewer-Dobson circulation, which is a single celled circulation, spanning from the tropics up to the poles, consisting of the tropical upwelling of air from the tropical troposphere and the extra-tropical downwelling of air. Stratospheric circulation is a predominantly wave-driven circulation in that the tropical upwelling is induced by the wave force by the westward propagating Rossby waves, in a phenomenon called Rossby-wave pumping. An interesting feature of stratospheric circulation is the quasi-biennial oscillation (QBO) in the tropical latitudes, which is driven by gravity waves that are convectively generated in the troposphere.
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Overlooked Ocean Worlds Fill the Outer Solar System. John Wenz, Scientific American. October 4, 2017. In September 2016, scientists at Brown University simulated the impact thought to have formed Sputnik Planitia, and showed that it might have been the result of liquid water upwelling from below after the collision, implying the existence of a subsurface ocean at least 100 km deep.
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This is due to the moderate upwelling, which causes lower turbulence, as well as a weakened Ekman drift offshore. These two species experience population shifts related to climate changes and environmental events such as El Niño. This is due to changes in the availability of each species habitat. Anchoveta are an important component in the diets of marine mammals, seabirds, and larger fish.
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Upwelling magma vaporized the ocean water and steam explosions blew the magma into fine ash. The explosions built cones or rings of ash, which solidified into tuff. The eruptions shattered the sea floor—coral reef and basalt—and scattered pieces that are now embedded in the tuff. Wave erosion eventually cut through the low, southeast wall of the crater, forming the current bay.
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Megalodon inhabited a wide range of marine environments (i.e., shallow coastal waters, areas of coastal upwelling, swampy coastal lagoons, sandy littorals, and offshore deep water environments), and exhibited a transient lifestyle. Adult megalodon were not abundant in shallow water environments, and mostly inhabited offshore areas. Megalodon may have moved between coastal and oceanic waters, particularly in different stages of its life cycle.
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This upwelling supplies large quantities of nutrients to the surface, which supports biological activity. Surface supply of nutrients is critical to the ocean's functioning as a carbon sink on long timescales. Furthermore, upwelled water has low concentrations of dissolved carbon, as the water is typically 1000 years old and has not been sensitive to anthropogenic CO2 increases in the atmosphere.
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The Samoa hotspot is marked 35 on map. The Samoa hotspot is a volcanic hotspot located in the south Pacific Ocean. The hotspot model describes a hot upwelling plume of magma through the Earth's crust as an explanation of how volcanic islands are formed. The hotspot idea came from J. Tuzo Wilson in 1963 based on the Hawaii volcanic island chain.
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The hurricane turned to the southeast, after the cold front bypassed the system and the ridge rebuilt. Over the next day, Roxanne stalled off the northwest coast of the Yucatán Peninsula. Drier air, wind shear, and upwelling caused the hurricane to weaken back to a tropical storm. By late on October 17, the circulation had little convection associated with it.
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The water upwelling at Zmudowski State Beach has affected wildlife, particularly the fish population. Certain nutrients from the water rise to the surface, and stimulate high plankton productivity of the Monterey Bay region. The high nutrient content, salinity and density make this area attractive to anglers, year-round. Accordingly, Zmudowski State Beach is ranked a three star as a popular fishing destination.
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Some stocks migrate in large schools along the coast to suitable spawning grounds, where they spawn in fairly shallow waters. After spawning they return the way they came in smaller schools to suitable feeding grounds, often near an area of upwelling. From there they may move offshore into deeper waters and spend the winter in relative inactivity. Other stocks migrate across oceans.
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It then slowly returns poleward near the surface to repeat the cycle. The continual diffuse upwelling of deep water maintains the existence of the permanent thermocline found everywhere at low and mid-latitudes. This model was described by Henry Stommel and Arnold B. Arons in 1960 and is known as the Stommel-Arons box model for the MOC.Stommel, H., & Arons, A. B. (1960).
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MOPITT satellite computer image of carbon monoxide March 2010. MOPITT is a nadir sounding (vertically downward pointing) instrument that measures upwelling infrared radiation at 4.7 μm and 2.2-2.4 μm. It uses correlation spectroscopy to calculate total column observations and profiles of carbon monoxide in the lower atmosphere. Although observations of methane were also planned, to date no data have been released.
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The isostatic response to the detachment of the downgoing slab is rapid uplift. Slab detachment is also followed by the upwelling of relatively hot asthenosphere to fill the gap created, leading in many cases to magmatism. The uncritical use of the slab-detachment model to explain disparate observations of magmatism, uplift and exhumation in continental collision zones has been criticised.
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Another peculiarity of the Strait of Messina is the presence of a varied and numerous bathypelagic fauna that, transported to the surface by the upwelling current from the South, can be easily captured still alive in the points of greater turbulence, or found stranded along the coasts after adverse weather conditions. Examples are Chauliodus sloani, Argyropelecus hemigymnus and Myctophum punctatum.
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The Louisville Ridge Stretching for 4,300 km north- west from the Pacific-Antarctic Ridge to the Osbourn Seamount at Tonga and Kermadec Junction is a long line of seamounts called the Louisville Ridge – the longest such chain in the Pacific – thought to have formed from the Pacific Plate sliding over a long-lived center of upwelling magma called the Louisville hotspot.
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It has been shown that AT is often inversely proportional to sea surface temperature (SST). Therefore, it generally increases with high latitudes and depths. As a result, upwelling areas (where water from the deep ocean is pushed to the surface) also have higher alkalinity values.Millero, F. J.; Lee, K.; Roche, M. Distribution of alkalinity in the surface waters of the major oceans.
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Given continued favorable conditions, forecasters at the NHC predicted Blanca to achieve Category 5 status—the highest ranking on the scale, indicating winds in excess of . Contrary to forecasts, the still quasi-stationary Blanca soon degraded. The hurricane's persistence over the same location for several days resulted in tremendous upwelling of cooler waters, with temperatures underneath the storm falling from .
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Point Arena is one of the major upwelling zones along the West coast of the U.S., which means it is a source of nutrients for fish and wildlife. Kelp forests and rocky reefs shelter red abalone at Arena Rock and underwater caves host a highly diverse fish fauna that once included abundant populations of yelloweye and vermillion rockfish, lingcod and giant Pacific octopus.
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The slow movement caused upwelling, which cooled the waters, thus weakening the cyclone despite otherwise favorable conditions. The central core of convection diminished and became restricted to the eastern side of the circulation. On October 13, thunderstorm activity increased over the center, signaling some re- intensification. Luban again weakened as it approached land, affected by the cooler water and air temperatures.
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However albatrosses are not able to reach the adults because they cannot deep-dive. Tissue degeneration and upwelling bring mature squids up to the surface of the water for predation. Digested parts of G. glacialis have been found in the stomachs of a species of icefish native to the Southern Ocean. Galiteuthis glacialis are opportunistic feeders and prey upon whatever is available.
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Wind Driven Surface Currents: Upwelling and Downwelling These can transport nutrients which plankton thrive on. The result can be rich feeding grounds attractive to the plankton feeding forage fish. In turn, the forage fish themselves become a feeding ground for larger predator fish. Most upwellings are coastal, and many of them support some of the most productive fisheries in the world.
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Regions of notable upwelling include coastal Peru, Chile, Arabian Sea, western South Africa, eastern New Zealand and the California coast. Capelin are a forage fish of the smelt family found in the Atlantic and Arctic oceans. In summer, they graze on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat krill and other crustaceans.
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The array consists of two lines of moorings, one off Newport, Oregon (the Oregon Line) and the other off Grays Harbor, Washington (the Washington Line). Gliders sample between the mooring lines. The array focuses on observing the influence of the Columbia River on the coastal ecosystem. It also samples a prototypical upwelling regime on a narrow continental shelf where anoxia events are common.
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The river originates in an upwelling of the waters of the aquifer under the forest of Velours in the commune of Lux, Côte-d'Or. This is fed by water from the Tille and Venelle rivers. The Speleo-Club of Dijon has explored the source since 14 July 1950. Exploration continues today by scuba diving and by systematic study of the discovered network.
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Downwelling and Upwelling processes in the open ocean leads to a warm-core in Anticyclonic eddies and a cold-core in Cyclonic eddies. The fast-moving currents in the Gulf Stream meander and pinch-off to create eddies. These eddies retain the physical properties of their parent water mass (e.g. temperature, density, salinity, and other ocean dynamic properties) when they separate.
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Some of these volcanic centres are occasionally grouped with Ashikule in the Yutian- Yumen volcanic zone. A pronounced seismic velocity anomaly in southern Tarim may be associated with the volcanism at Ashikule, and a seismically imaged gap between the Tarim block and the Indian Plate below the crust may be a pathway for mantle upwelling that feeds the Ashikule volcanoes.
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Coastal upwellings and tides are a huge issue for Hood Canal. Because of the lack of upwelling and tides pushing in oxygen rich waters into the canal, the area's oxygen content suffers. Unfortunately, since the Puget Sound ecosystem is so large, it would be very difficult to oxygenate deeper waters. But surface-level DO could be improved by restoring natural flows of estuaries.
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This marine forest habitat is beneficial for many fish species, and the kelp itself is a renewable resource for food, animal feed, medicines and various other commercial products. It is also a powerful tool for carbon fixation. The upwelling can be powered by renewable energy on location. Vertical mixing has been reduced due to ocean stratification effects associated with climate change.
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Malgas Island is a small, , uninhabited island lying in the northern part of the entrance to Saldanha Bay, in the Western Cape province of South Africa. It lies about from the mainland in the Benguela upwelling system. It is circular in shape and flat, with the highest point about above sea level. It is known for its large breeding colony of Cape gannets.
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It also has one of the better simulations of El Nino among the IPCC models (van Oldenburgh et al., 2005; Wittenberg et al., 2006). However, as is the case with most AOGCMs run without flux adjustment, the models fail to capture the cold upwelling zones along the eastern boundaries of the Pacific and Atlantic, and tend to produce an overly dry Amazon basin.
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It is conspicuous that penguins and plotopterids – both wing-propelled divers that foraged over the continental shelf – are almost invariably found in the company of pseudotooth birds. Thus, pseudotooth birds seem to have gathered in some numbers in upwelling regions, presumably to feed but perhaps also to breed nearby.Hopson (1964), Olson (1985: pp. 200–201), Ono (1989), del Hoyo et al.
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Sea surface temperatures in the wake of Cyclone Mala decreased up to 4–5 °C (7–9 °F) due to upwelling. From April 28–29, the low-level inflow associated affected much of the northern Bay of Bengal and resulted in northwesterly winds as far away as Hyderabad, India. These winds brought dry, dust filled air over the bay with mean particulate-matter doubling over the region.
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The subducting slab undergoes backward sinking due to the negative buoyancy forces causing a retrogradation of the trench hinge along the surface. Upwelling of the mantle around the slab can create favorable conditions for the formation of a back-arc basin. Seismic tomography provides evidence for slab rollback. Results demonstrate high temperature anomalies within the mantle suggesting subducted material is present in the mantle.
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Basalt is the most common volcanic rock type on Earth. The crustal portions of oceanic tectonic plates are composed predominantly of basalt, produced from upwelling mantle below the ocean ridges.Philpotts and Ague 2009, pp.366-368 Basalt is also the principal volcanic rock in many oceanic islands, including the islands of Hawaiʻi,Philpotts and Ague 2009, pp.365-370 the Faroe Islands,Schminke 2003, p.
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Large amounts of carbon are exchanged each year between the ocean and the atmosphere. A major controlling factor in oceanic- atmospheric carbon exchange is thermohaline circulation. In regions of ocean upwelling, carbon-rich water from the deep ocean comes to the surface and releases carbon into the atmosphere as carbon dioxide. Large amounts of carbon dioxide are dissolved in cold water in higher latitudes.
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This water sinks down and brings the carbon into the deeper ocean levels, where it can stay for anywhere between decades and several centuries. Ocean circulation events cause this process to be variable. For example, during El Nino events there is less deep ocean upwelling, leading to lower outgassing of carbon dioxide into the atmosphere. Biological processes also lead to ocean-atmosphere carbon exchange.
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Siliceous ooze is present along the seafloor in these subpolar regions. Ocean basin boundary currents, such as the Humboldt Current and the Somali Current are examples of other upwelling currents that favor the formation of siliceous ooze. Siliceous ooze is often categorized based upon its composition. Diatomaceous oozes are predominantly formed of diatom skeletons and are typically found along continental margins in higher latitudes.
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Fossil evidence suggests that radiolarians first emerged during the late Cambrian as free-floating shallow water organisms. They did not become prominent in the fossil record until the Ordovician. Radiolarites evolved in upwelling regions in areas of high primary productivity and are the oldest known organisms capable of shell secretion. The remains of radiolarians are preserved in chert; a byproduct of siliceous ooze transformation.
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Landschützer, Peter, et al. "The reinvigoration of the Southern Ocean carbon sink." Science 349.6253 (2015): 1221–1224. After upwelling, the water is understood to take one of two pathways: water surfacing near to sea-ice generally forms dense bottomwater and is committed to AMOC's lower cell; water surfacing at lower latitudes moves further northward due to Ekman transport and is committed to the upper cell.
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Otariids are carnivorous, feeding on fish, cephalopods and krill. Sea lions tend to feed closer to shore in upwelling zones, feeding on larger fish, while the smaller fur seals tend to take longer, offshore foraging trips and can subsist on large numbers of smaller prey items. They are visual feeders. Some females are capable of dives of up to 400 m (1,300 ft) depth.
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Wind forcing and topography play a large role in the circulation and flow of the coastal waters. The Oregon coast experiences seasonal wind forcing and subsequently operates under two distinct systems: upwelling and downwelling. In the summer months, typically April to September, wind flow is generally southward. These southward flowing winds cause surface currents to move away from the coastline, in a process known as Ekman transport.
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Anaerobic forms of respiration, such as denitrification, consume nitrate rather than O2. Denitrification appears to be particularly important in shelf sediments in the California current system, due to the seasonally hypoxic bottom waters that typically emerge during summer upwelling. Further, denitrification in the Heceta Bank region by bacteria frees up O2 to be utilized by other organisms like rockfish and other demersal fish species.
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The convection continued to weaken due to continued shear and cooler waters from upwelling, and Krosa deteriorated to tropical storm status on November 3. The next day, the JTWC issued its final advisory after the circulation became exposed from the convection. Also on November 4, the JMA downgraded Krosa to tropical depression status off the northeast Vietnam coast. The system dissipated at 0000 UTC on November 5.
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Chiropsoides buitendijki have been shown to experience blooms in coastal upwelling regions, especially after monsoon season when the nutrients in the water are well mixed and distributed. However, these blooms in the Indian Ocean bring large numbers of jellyfish to coastal waters, where they are susceptible to bycatch from large fishing vessels. The jellyfish are not typically eaten, so a majority of catch is discarded on board.
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The potential indirect mortality associated with P. australis is of great concern to humans as toxic algae blooms, including blooms of P. australis, continue to increase in frequency and severity over recent years. Blooms of P. australis are believed to result from high concentrations of nitrates and phosphates in stream and river runoff, as well as coastal upwelling, which are also sources of other harmful algae blooms.
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The temperature at the cloud-tops in each polar vortex is much higher than in the nearby polar collars, reaching 250 K (−23 °C). The conventional interpretation of the polar vortices is that they are anticyclones with downwelling in the centre and upwelling in the cold polar collars. This type of circulation resembles a winter polar anticyclonic vortex on Earth, especially the one found over Antarctica.
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The ecosystem of the Humboldt current is affected by the El Niño phenomenon. During the El Niño, upwelling of nutrient-rich bottom water in the south-eastern Pacific Ocean is depressed, as well as sea surface temperature anomaly (SSTA) value increases. Massive mortality, especially of juveniles, nest desertion and lack of reproduction occurs. Humboldt penguins migrate south as marine productivity decreases, following the anchovy stocks.
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Mozambique and East Madagascar Currents, which meet south- west of Madagascar (not shown in the diagram). The cold Benguela Current originates from upwelling of water from the cold depths of the Atlantic Ocean against the west coast of the continent. The two currents do not "meet" anywhere along the south coast of Africa. The Agulhas Current is the western boundary current of the southwest Indian Ocean.
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Seasonal upwelling along the Pacific North American coast has been correlated to increased sea lettuce productivity and decreased eelgrass productivity. Japanese eelgrass (Zostera japonica) is an introduced species found in bays and estuaries ranging from Oregon to British Columbia, Canada. It was likely brought over by Pacific oyster seed shipments that began in the early 20th century used by commercial shellfisheries along the Pacific northwest coast.
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There is some evidence that global warming has resulted in some decrease of the salinity of the waters of the Ross Gyre since the 1950s. Due to the Coriolis effect acting to the left in the Southern Hemisphere and the resulting Ekman transport away from the centres of the Weddell Gyre, these regions are very productive due to upwelling of cold, nutrient rich water.
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These small home ranges suggest that dispersal of the species is mainly by planktonic larvae. Activity is markedly reduced during the night, and when cold-water upwelling occur, fish seek the shelter of caves. Over the spawning period, females wander beyond their normal home boundaries. This species is sought after by line fishers, operating from the shore or from boats within the inshore zone.
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Mycoplankton and heterotrophic bacteria mediate carbon, nitrogen, oxygen, and other nutrient fluxes in marine ecosystems. It has been shown that there are higher concentrations of mycoplankton near the surface and in shallow waters, which indicates their connection with the upwelling of organic matter. This further correlates with abundant phytoplankton communities at the surface, implying that mycoplankton is intimately involved in organic matter consumption in the euphotic zone.
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In the weeks and months after the passage of Sudal, water temperatures around Yap decreased from to , due to significant upwelling. The drastic decrease caused unusual amounts of fog over the island, as well as significantly lower tides. By September 2004, rebuilding was still underway, and half of the schools, which had previously been used as shelters, reopened to students. Power and water lines were completely restored.
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Most commonly, iron was available as an inorganic source to phytoplankton; however, organic forms of iron can also be used by specific diatoms which use a process of surface reductase mechanism. Uptake of iron by phytoplankton leads to lowest iron concentrations in surface seawater. Remineralization occurs when the sinking phytoplankton are degraded by zooplankton and bacteria. Upwelling recycles iron and causes higher deep water iron concentrations.
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Mozambique and East Madagascar Currents, which meet south-west of Madagascar (not shown in the diagram). The cold Benguela Current originates from upwelling of water from the cold depths of the Atlantic Ocean against the west coast of the continent. The two currents do not "meet" anywhere along the south coast of Africa. The Agulhas Current is the western boundary current of the southwest Indian Ocean.
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The Agulhas acts as an oceanic convergence zone. Due to mass continuity this drives surface waters down, resulting in the upwelling of cold, nutrient rich water south of the current. Additionally, the convergence tends to increase the concentration of plankton in and around the Agulhas. Both of these factors result in the area being one of enhanced primary productivity as compared to the surrounding waters.
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The Agulhas acts as an oceanic convergence zone. Due to mass continuity this drives surface waters down, resulting in the upwelling of cold, nutrient rich water south of the current. Additionally, the convergence tends to increase the concentration of plankton in and around the Agulhas. Both of these factors result in the area being one of enhanced primary productivity as compared to the surrounding waters.
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A rift is the result of pulling apart or extension of both the lithosphere and crust (note that the crust is a part of the lithosphere). This is a product of what is referred to as mantle upwelling where hotter asthenosphere rises up into colder lithosphere. This rise is associated with thinning and stretching of the lithosphere. The internal dynamics of a rift system.
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Subpolar gyres form at high latitudes (around 60°). Circulation of surface wind and ocean water is counterclockwise in the Northern Hemisphere, around a low-pressure area, such as the persistent Aleutian Low and the Icelandic Low. Surface currents generally move outward from the center of the system. This drives the Ekman transport, which creates an upwelling of nutrient-rich water from the lower depths.
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Regions of significant net DOC production (broad arrows) include coastal and equatorial upwelling regions that support much of the global new production. DOC is transported into and around the subtropical gyres with the wind-driven surface circulation. Export takes place if exportable DOC (elevated concentrations indicated by dark blue fields) is present during overturning of the water column. precursor for deep and intermediate water mass formation.
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Red tide in a harbor, Japan Red tide is a common name for algal blooms, which are large concentrations of aquatic microorganisms, such as protozoans and unicellular algae (e.g. dinoflagellates and diatoms). The upwelling of nutrients from the sea floor, often following massive storms, provides for the algae and triggers bloom events. Harmful algal blooms can occur worldwide, and natural cycles can vary regionally.
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The lack of motion resulted in upwelling which imparted additional weakening, and Aletta weakened to tropical storm status on May 27. It quickly deteriorated that day, and on May 28 the system dissipated well south of Cabo San Lucas after it began a slow north drift. The remnants lingered in the same area for the next several days. Aletta caused no known damages or casualties.
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Stratified waters, in combination with slow vertical mixing, are essential to maintaining euxinic conditions. Stratification occurs when two or more water masses with different densities occupy the same basin. While the less dense surface water can exchange gas with the oxygen-rich atmosphere, the denser bottom waters maintain low oxygen content. In the modern oceans, thermohaline circulation and upwelling prevent the oceans from maintaining anoxic bottom waters.
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The winds drive surface water to the right of the wind flow, that is offshore, which draws water up from below to replace it. The upwelling further cools the already cool California Current. This is the mechanism that produces California's characteristic coastal fog and cool ocean waters. As a result, ocean surf temperatures are much colder along the Pacific coast than the Atlantic coast.
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"East Africa: Coral reef programs of eastern Africa and the Western Indian Ocean". International Tropical Marine Ecosystems Management Symposium (ITMEMS) Proceedings, 1998. Fringing reefs are uncommon along the Mozambican coast, limited by freshwater input from numerous rivers, and cold-water upwelling in the Mozambique Channel. Patch reefs are best developed on the Quirimbas Islands, Primeiras and Segundas Archipelago, and Mozambique Island and neighboring islands in Mozambique Bay.
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By September 2, the storm curved north-northwestward while located north of the Leeward Islands. Thereafter, a blocking pattern over Atlantic Canada caused Leslie to drift for four days. Late on September 5, Leslie was upgraded to a Category 1 hurricane. However, due to its slow movement, the storm causing upwelling, which decreased sea surface temperatures (SST's), weakening Leslie back to a tropical storm on September 7\.
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The oxygen level may also be partially due to a change in wind direction. The prevailing north wind generally pushes oxygenated water into the oxygen-depleted area. A sustained south wind will cut off this source of oxygen. Coastal upwelling from the Strait of Juan de Fuca bring in a surplus of nutrients into the Puget Sound, but fail to circulate oxygen through Hood Canal.
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The crater Mersenius N lies across the southwestern rim. The interior has been flooded by basaltic lava, which bulges upwards forming a convex domed shape with an estimated height of 450 metres relative to the floor edges. This was most likely formed by lava upwelling beneath the surface. There are several tiny craterlets across the floor surface, but little in the way of a central peak.
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The Chumash tribes near the coast benefited most with the "close juxtaposition of a variety or marine and terrestrial habitats, intensive upwelling in coastal waters, and intentional burning of the landscape made the Santa Barbara Channel region one of the most resource abundant places on the planet."(Newton 416). While droughts were not uncommon in the centuries of the first millennium AD, a population explosion occurred with the coming of the medieval warm period. "Marine productivity soared between 950 and 1300 as natural upwelling intensified off the coast."Fagan, The Long Summer, 2004, p. 222 Before the mission period, the Chumash lived in over 150 independent villages, speaking variations of the same language. Much of their culture consisted of basketry, bead manufacturing and trading, cuisine of local abalone and clam, herbalism which consisted of using local herbs to produce teas and medical reliefs, rock art, and the scorpion tree.Barry.
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Aboriginal trade networks are believed to have deteriorated following European occupation. Governor Arthur Phillip explored the Prospect area in 1788 south west of the end of the headwaters of the Parramatta River and named the wide low hill Bellevue Hill (the hill is an ancient volcanic upwelling referred to as a 'Doleritic Laccolith'). Bellevue means "Fine Prospect". The area later became known as Prospect Hill and then gradually as Prospect.
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On 2 October, Zorbas moved over northwestern Turkey and dissipated. A cold wake was observed in the Mediterranean Sea, with sea surface temperatures dropping along the track of Zorbas due to strong upwelling. During its formative stages, the storm caused flash flooding in Tunisia and Libya, with around 200 mm (8 in) of rainfall observed. The floods killed five people in Tunisia, while also damaging homes, roads, and fields.
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He was known for his audacity: his Apologetic against Muhammad -- known only from fragments --, written during the most dangerous period of the Muslim invasion, condemned Christians who converted to Islam. Speraindeo's agitation of the Christian community in Córdoba resulted in an upwelling of religious fervor, and ultimately produced a wave of new martyrs collectively known as Martyrs of Córdoba. Among his disciples were Saint Eulogius, Alvarus Paulus, and Samson of Córdoba.
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Several studies, including and have compiled box and gravity cores in the North Pacific analyzing them for palynological content to determine the distribution of dinocysts and their relationships with sea surface temperature, salinity, productivity and upwelling. Similarly, and use a box core at 576.5 m of water depth from 1992 in the central Santa Barbara Basin to determine oceanographic and climatic changes during the past 40 kyr in the area.
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Abudefduf troschelii spawn within nine days on either side of the new moon, and hatching occurs after four days where newborns are hatched during the hour after sunset. Extended periods of spawning can occur during seasonal increases in plankton productivity. This seasonal increase is due to upwelling and leads to an increase in egg production of the species. During a wet season, this reproductive process lasts three to four days.
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These values are not outstandingly high, compared to very productive areas like the North Sea or upwelling regions, but the area over which it takes place is enormous, even compared to other large primary producers such as rainforests. In addition, during the Austral summer there are many hours of daylight to fuel the process. All of these factors make the plankton and the krill a critical part of the planet's ecocycle.
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The fact that there is size dependent predation on chelonians has led to the evolutionary development of large body sizes. In 1987, Carr discovered that the young of green and loggerhead sea turtles spent a great deal of their pelagic lives in floating sargassum mats. Within these mats, they found ample shelter and food. In the absence of sargassum, young sea turtles feed in the vicinity of upwelling "fronts".
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Kitchingman, A., Lai, S., Morato, T., and Pauly, D. (2007). "How many seamounts are there and where are they located?" p.26-40 in Seamounts: Ecology, Fisheries and Conservation. T.J. Pitcher, T. Morato, P.J.B. Hart, M.R. Clark, N. Haggan, and R.S. Santos (eds), Fish and Aquatic Resource Series, Blackwell, Oxford, UK. Seamounts enhance water flow through localised tides, eddies, and upwelling, and these physical processes may enhance primary production.
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The species are mostly pelagic: sardines, anchovies and jack mackerel. The system's high productivity supports other important fishery resources as well as marine mammals (eared seals and cetaceans) and seabirds. Periodically, the upwelling that drives the system's productivity is disrupted by the El Niño-Southern Oscillation (ENSO) event, often with large social and economic impacts. The Humboldt has a considerable cooling influence on the climate of Chile, Peru and Ecuador.
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Berkeley has a warm-summer Mediterranean climate (Csb) in the Köppen climate classification), with warm, dry summers and cool, wet winters. Berkeley's location directly opposite the Golden Gate ensures that typical eastward fog flow blankets the city more often than its neighbors. The summers are cooler than a typical Mediterranean climate thanks to upwelling ocean currents along the California coast. These help produce cool and foggy nights and mornings.
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Muller-Karger, F. E., R. Varela, R. Thunell, M. Scranton, R. Bohrer, G. Taylor, J. Capelo, Y. Astor, E. Tappa, T. Y. Ho, and J. J. Walsh. (2001). Annual Cycle of Primary Production in the Cariaco Basin: Response to upwelling and implications for vertical export. J. Geophys. Res. 106:C3. 4527-4542.Muller-Karger, F. E., R. Varela, R. Thunell, Y. Astor, H. Zhang, and C. Hu. (2004).
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At the mid-ocean divergent boundaries new magma is produced by mantle upwelling and a shallow melting zone. This juvenile basaltic magma is an early phase of the igneous portion of the cycle. As the tectonic plates on either side of the ridge move apart the new rock is carried away from the ridge, the interaction of heated circulating seawater through fractures starts the retrograde metamorphism of the new rock.
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This made Lorenzo the easternmost Category 5 Atlantic hurricane on record. After reaching peak intensity, Lorenzo began weakening due to upwelling and rapidly increasing southwesterly wind shear. Lorenzo dropped below major hurricane intensity at 18:00 UTC on September 29, only 15 hours after its peak intensity. Lorenzo then slowly weakened and its windfield expanded as the storm began an extratropical transition while passing northwest of the Azores.
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Most coral reefs exist in waters less than 50 m deep. Some inhabit tropical continental shelves where cool, nutrient-rich upwelling does not occur, such as the Great Barrier Reef. Others are found in the deep ocean surrounding islands or as atolls, such as in the Maldives. The reefs surrounding islands form when islands subside into the ocean, and atolls form when an island subsides below the surface of the sea.
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This, along with the positive gravity anomaly observed, implies a recently active region. Further evidence is observed in the Boala Corona (which lies inside, and postdates the Quetzalpetlatl Corona), where the grabens formed in the depression of the Corona are interpreted to be surface manifestations of terrestrial dikes. The mantle upwelling associated with hot spot tectonism appears to be the dominant process which formed and evolved the Lada Rise.
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The modern Manihiki Plateau rifted from the Hikurangi Plateau, now located adjacent to New Zealand, in the Early Cretaceous. In the Early Cretaceous the Manihiki Plateau was much shallower, below sea level or less. Shortly after emplacement the initiation of the Tongareva triple junction resulted in extension, upwelling and rifting. Renewed rifting at about 116 Ma created the eastern margin, the Manihiki Scarp, and separated Manihiki and Hikurangi.
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New magma of basalt composition emerges at and near the axis because of decompression melting in the underlying Earth's mantle. The isentropic upwelling solid mantle material exceeds the solidus temperature and melts. The crystallized magma forms new crust of basalt known as MORB for mid-ocean ridge basalt, and gabbro below it in the lower oceanic crust. Mid-ocean ridge basalt is a tholeiitic basalt and is low in incompatible elements.
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In oligotrophic oceanic regions such as the Sargasso Sea or the South Pacific Gyre, phytoplankton is dominated by the small sized cells, called picoplankton and nanoplankton (also referred to as picoflagellates and nanoflagellates), mostly composed of cyanobacteria (Prochlorococcus, Synechococcus) and picoeucaryotes such as Micromonas. Within more productive ecosystems, dominated by upwelling or high terrestrial inputs, larger dinoflagellates are the more dominant phytoplankton and reflect a larger portion of the biomass.
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Pulled slowly southeastward by a passing cold front, Chris intensified little throughout the rest of the day due to upwelling. However, on July 10, a developing trough over the northeastern United States accelerated Chris eastward into warmer waters, allowing for the formation of an inner core. With a well-defined eye and impressive appearance on satellite imagery, Chris strengthened into a hurricane at 12:00 UTC that day.
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A Great white shark near Dyer Island The shelf edge along the bank's southern tip is subject to sporadic upwelling. This slope and its surrounding seamounts are the spawning ground for sardine, anchovy, and horse mackerel. Eddies help transport water inshore and link the spawning habitat with important nursery areas. Eggs and larvae laid by the anchovy are transported via the Good Hope Jet to Africa's southwestern coast where they mature.
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The distribution of kingklip larvae was studied over a 12-month period, and yielded data on spawning areas and breeding seasons. The researchers concluded that there are different spawning strategies for the western Agulhas Bank and the West Coast. On the Agulhas Bank, spawning is initiated by a decrease in sea surface temperature, whereas on the West Coast, spawning only occurs when upwelling has decreased i.e. between June and December.
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Now Southern California, mostly areas around the Channel Islands, comprises 90% of the squid landings. The fishery in Monterey Bay occurs from April to November coinciding with the upwelling season. In Southern California landings begin in November and continue through April correlated with the greater mixing of winter storms. Since 1993 squid has been the #1 fishery in California with landings of 118,000 tons and $41 million in 2000.
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Common and Antarctic minke whales diverged from each other in the Southern Hemisphere 4.7 million years ago, during a prolonged period of global warming in the early Pliocene which disrupted the Antarctic Circumpolar Current and created local pockets of upwelling, facilitating speciation by fragmenting populations. The radiation of common minke whales into the Northern Hemisphere occurred rapidly about 1.5 million years ago during a period of cooling in the Pleistocene.
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The climate of the area is tropical, varying from tropical rainforest in some areas to tropical savanna in others. There are also some locations that are arid climates with considerable drought in some years. Rainfall varies with elevation, size and water currents (cool upwelling keep the ABC islands arid). Warm, moist trade winds blow consistently from the east, creating both rain forest and semi arid climates across the region.
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In September 1994, the Hubble telescope – using Wide Field Planetary Camera 2 – imaged storms on Saturn generated by upwelling of warmer air, similar to a terrestrial thunderhead. The east-west extent of the same-year storm equalled the diameter of Earth. The storm was observed earlier in September 1990 and acquired the name Dragon Storm. The dust storms of Mars vary in size, but can often cover the entire planet.
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Such seasonal extremes effectively accustom Oculina varicosa to wide temperature shifts. This temperature resilience indicates that O. varicosa may be more apt to survive despite rising global ocean temperatures. Temperate corals, such as Oculina arbuscula and Astrangia poculata, show relatively high tolerance to ocean warming because of these large seasonal shifts. During upwelling events at the Oculina Bank, temperatures can settle around 7 degrees Celsius for days at a time.
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They are fed high quality microalgae and diatoms and grow fast. At metamorphosis the juveniles may be allowed to settle on PVC sheets or pipes, or crushed shell. In some cases, they continue their development in "upwelling culture" in large tanks of moving water rather than being allowed to settle on the bottom. They then may be transferred to transitional, nursery beds before being moved to their final rearing quarters.
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In 2015, Fawcett was appointed a lecturer in oceanography at the University of Cape Town. She has worked to build up a diverse research group, aware of the discrimination still faced by female scientists. From 2016, she has participated in the SEAmester scheme that aims to train up postdoctoral oceanography researchers. In her doctorate Fawcett investigated the relationship between nitrogen and populations of phytoplankton in upwelling ecosystems of the Sargasso Sea.
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Upwelling brings nutrient-rich water to the surface, stimulating abundant growth of phytoplankton, which then settles to the bottom (a phenomenon known as the biological pump). Thus, there is a lot of organic material in the sediments, and all the oxygen is used up in its consumption. They have very stable temperature and pressure profiles. The population of microbes is orders of magnitude greater than in the abyssal plains.
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The isotopes dissolved in water are particularly useful in studying global circulation. For example, differences in lateral isotopic ratios within an ocean can indicate strong water fronts or gyres. Conversely, the isotopes attached to particles can be used to study mass transport within water columns. For instance, high levels of Am or Pu can indicate downwelling when observed at great depths, or upwelling when observed at the surface.
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Rain and snowmelt from the surrounding mountains and upwelling from deep groundwater within the basin periodically fill Lake Lucero with water containing dissolved gypsum. When filled, the lake covers about at a depth of . As the water evaporates, small selenite crystals about in diameter form on the surface of the lake. Most of the crystal formation occurs when large floods concentrate the mineralized water every ten to fourteen years.
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The extensive mangrove forests and coastal wetlands are important habitat for waterbirds, with over 73 species present.Pereira, Marcos & Litulo, Carlos & Santos, Rodrigo & Costa Leal, Miguel & Fernandes, Raquel & Tibirica, Yara & Williams, Jess & Atanassov, Boris & Carreira, Filipa & Massingue, Alice & Marques da Silva, Isabel. (2014). Mozambique marine ecosystems review. 10.13140/2.1.2092.5766. The turbid waters of the region, along with occasional cold-water upwelling, limits the growth of corals in the region.
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Patch coral reefs occur around Kiunga on Kenya's northern coast, and along the southern Somali coast. Cool water upwelling along the coast limits the development of coral reefs, and they are not as well developed as those in the East African coral coast further south. The Lamu Archipelago has extensive mangroves, covering approximately 32,000 ha – nearly 70% of Kenya's mangrove area.Nyawira Muthiga, Lionel Bigot and Agneta Nilsson (1998).
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Onatah Corona is a corona (a geological feature) on Venus adjacent to Ba'het Corona. Both features are surrounded by a ring of ridges and troughs, which in places cut more radially-oriented fractures. The centers of the features also contain radial fractures as well as volcanic domes and flows. Coronae are thought to form due to the upwelling of hot material from deep in the interior of Venus.
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The Mesozoic is well known for its distinct Ocean Anoxic Events (OAEs) which resulted in the burial of layers of black shale. Although these OAEs are not stand alone evidence for euxinia, many do contain biomarkers which support euxinic formation. Again, evidence is not universal. OAEs may have spurred the spread of existing euxinia, especially in upwelling regions or semi-restricted basins, but photic zone euxinia did not happen everywhere.
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This prevents nutrient-rich upwelling which has reduced productivity. Georges Bank and the Gulf of Maine are affected by this reduced cod catch. The strength of the NAO is also a determinant in the population fluctuations of the intensively studied Soay sheep. Strangely enough, Jonas and Joern (2007) found a strong signal between NAO and grasshopper species composition in the tall grass prairies of the midwestern United States.
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The influence of tectonic activity is very evident in the area. There are many depressions, solution valleys, small karst poljes, and the remains of former river valleys. During the Pliocene the rivers leveled the tectonic upwelling and filled the valleys. Traces were also left by Pliocene glaciation because glaciers created small cirques on what had been a relatively level surface, as well as ground moraines and terminal moraines.
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The major sources of marine silica include rivers, groundwater flux, seafloor weathering inputs, hydrothermal vents, and atmospheric deposition (aeolian flux). Rivers are by far the largest source of silica to the marine environment, accounting for up to 90% of all the silica delivered to the ocean. A source of silica to the marine biological silica cycle is silica that has been recycled by upwelling from the deep ocean and seafloor.
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The climate of the Patagonian region is influenced both by the close distance to Antarctica and by the Southern Hemisphere Westerlies. Polar cold air outbreaks, cool ocean upwelling, orographic precipitation and the Antarctic Circumpolar Current further affect the regional climate. About four stages of glaciation have been recognized in the area during the Pleistocene, although the glacial history is poorly known. Monte Burney was glaciated during the last glacial maximum.
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Much of the zone lacks nutrients for supporting fish, so epipelagic fish tend to be found in coastal water above the continental shelves, where land runoff can provide nutrients, or in those parts of the ocean where upwelling moves nutrients into the area.Moyle and Cech, p. 571 Epipelagic fish can be divided broadly into small forage fish and larger predator fish that feed on them. Forage fish school and filter feed on plankton.
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The rerouting of ocean currents led to climatic changes as the Earth entered a glacial cycle. Cold water upwelling around the Cape of Good Hope and reduction in water temperature at Cape Horn formed coldwater barriers to migrating turtles. The result was a complete isolation of the Atlantic and Pacific populations of loggerheads. During the most recent ice age, the beaches of southeastern North America were too cold for sea turtle eggs.
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Nutrients from rivers along with mixing and upwelling from storms contribute mixed layer nutrients which are essential for Arctic phytoplankton development. During summer, nearly continuous solar insolation encourages phytoplankta blooms. The Arctic Ocean is surrounded by continents and has a few narrow, relatively shallow connections to the large ocean basins to the south. Large amounts of riverine fresh water as well as abundant nutrients (gelbstoff) flow into the Arctic basin from Siberian rivers.
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The cyclone then levelled off in strength as the ocean upwelling beneath it abated. Bud made landfall near Cabo San Lucas shortly after 02:00 UTC on June 15, with winds of 45 mph (75 km/h), before progressing into the Gulf of California. Strong wind shear and land interaction reduced the storm to a remnant low by 12:00 UTC. On June 16 at 06:00 UTC, Bud's remnant low dissipated.
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This has led to historical fluctuations in water supply, which has been a crucial factor in the sustainability of human populations in certain sections of the various islands throughout the archipelago. This is especially evident in the low historical population of Ua Huka (maximum elevation 2,812 ft.) and the intermittent inhabitability of Eiao (maximum elevation 1,890 ft.). The Marquesas Islands are thought to have formed from a center of upwelling magma called the Marquesas hotspot.
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If there are not enough resources or producers in the ecosystem, there is not enough energy left for the rest of the animals in the food chain because of biomagnification and the ecological efficiency. An example would be how plankton populations are controlled by the availability of nutrients. Plankton populations tend to be higher and more complex in areas where upwelling brings nutrients to the surface. There are many different examples of these concepts.
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La Guaira Bank (),Pesquería artesanal de istiofóridos en Venezuela is a large, completely submerged bank in Venezuela. It is located in the Caribbean Sea 20 km to the NNE off the northern shore of La Guaira.La Guaira - Geographical Names This reef has an excellent reputation for deep-sea angling.Fishing El Placer Bank, la Guaira, Venezuela Currents create an upwelling of nutrients that attracts large pelagic fish such as sailfish, marlin, yellowfin tuna and mahi-mahi.
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2005 Tropical Eastern North Pacific Hurricane Outlook. . Retrieved May 2, 2006. Tropical cyclones also help maintain the global heat balance by moving warm, moist tropical air to the middle latitudes and polar regions, and by regulating the thermohaline circulation through upwelling. The storm surge and winds of hurricanes may be destructive to human-made structures, but they also stir up the waters of coastal estuaries, which are typically important fish breeding locales.
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As this energy is removed from the seas, a wake of colder water can be detected along the hurricane's path. This is because heat is withdrawn from the ocean mixed layer in a number of ways. For instance, sensible and latent heat are lost directly to the tropical cyclone across the air-sea interface. Also, the horizontal divergence of wind-driven mixed layer currents results in the upwelling of colder thermocline water.
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Much of the island's native plant cover, which outside the valleys consists primarily of dryland scrub, has been devastated by herds of feral goats and horses, which are estimated to number upwards of 3,000. Ua Huka is a shield volcano that was emplaced between 2.2 and 2.4 million years ago. It is thought to have formed by a center of upwelling magma called the Marquesas hotspot. The island is served by Ua Huka Airport.
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The current hotspot location is west of the spreading center known as the East Pacific Rise; an area near where the Nazca plate and the Pacific plate are diverging around 20°S, 115°W. This is where material is thought to be sourced from the core-mantle boundary, rising to surface as a localized plume. Opponents of the hotspot theory instead attribute Pitcairn hotspot to upwelling at the western end of the Easter Fracture Zone.
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Many geologists believe that the Wallowa Mountains in northeastern Oregon are a displaced fragment of the Insular Belt. The core of the Wallowas is composed of the Wallowa Batholith surrounded by Columbia River basalt. In addition there are many older terranes between the batholith and basalt flows. The Wallowa Batholith is formed of granite from a magma upwelling in Late Jurassic and Early Cretaceous time (between 160 million and 120 million years ago).
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In biological oceanography, new production is supported by nutrient inputs from outside the euphotic zone, especially upwelling of nutrients from deep water, but also from terrestrial and atmosphere sources (as opposite to regenerated production, which is supported by recycling of nutrients in the euphotic zone). New production depends on mixing and vertical advective processes associated with the circulation.Richard W. Eppley; Bruce J. Peterson. "Particulate organic matter flux and planktonic new production in the deep ocean".
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The Burubatial Formation, located in the West Balkhash region of Kazakhstan, is the oldest known abyssal biogenic deposit. The Burubaital Formation is primarily composed of chert which was formed over a period of 15 million years (late Cambrian-middle Ordovician). It is likely that these deposits were formed in an upwelling region in subequatorial latitudes. The Burubaital Formation is largely composed of radiolarites, as diatoms had yet to evolve at the time of its formation.
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Pacific oyster spat can be grown in nurseries by sea-based or land-based upwelling systems. Nursery culture reduces mortality in small spat, thus increasing the farm's efficiency. Sea-based nursery systems are often located in estuarine areas where the spat are mounted on barges or rafts. Land-based nursery systems have spat mounted on barges in large saltwater tanks, which either have a natural algae supply or are enriched with nutrients from fertilizers.
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500px NVPM are the result of rifting when a continent breaks up to form an ocean, producing transitional crust without volcanism. Extension causes a number of events to occur. First is lithospheric thinning, which allows asthenospheric upwelling; heating further erodes the lithosphere, furthering the thinning process. The extensional forces also cause listric faults and continentward dipping reflectors that help identify NVPM and distinguish them from VPM, characterized by seaward-dipping seismic reflectors.
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Insulated by the overlying roof rock, upwelling magma cooled slowly, and the mafic rock into which it cooled therefore is coarse-grained. These intrusions formed a sill some 16 km thick,Ojakangas & Matsch (1982), pp. 55–57. primarily of gabbro, but with significant amounts of anorthosite and other related granitic rocks.Jirsa & Southwick, Mineral Potential (2000); Topinka, America's Volcanic Past (2003); Miller, Green, Severson, Chandler, & Peterson, Geologic Map of the Duluth Complex (2001).
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The Iceland plume is a postulated upwelling of anomalously hot rock in the Earth's mantle beneath Iceland. Its origin is thought to lie deep in the mantle, perhaps at the boundary between the core and the mantle at approximately 2,880 km depth. Opinions differ as to whether seismic studies have imaged such a structure. In this framework, the volcanism of Iceland is attributed to this plume, according to the theory of W. Jason Morgan.
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Another model proposes that the upwelling in the Iceland region is driven by lateral temperature gradients between the suboceanic mantle and the neighbouring Greenland craton and therefore also restricted to the upper 200–300 km of the mantle. However, this convection mechanism is probably not strong enough under the conditions prevailing in the north Atlantic, with respect to the spreading rate, and it does not offer a simple explanation for the observed geoid anomaly.
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However, compared to protozoan grazing, the effect of viral lysis can be very different because lysis is highly host-specific to each marine bacteria. Both protozoan grazing and viral infection balance the major fraction of bacterial growth. In addition, the microbial loop dominates in oligotrophic waters, rather than in eutrophic areas - there the classical plankton food chain predominates, due to the frequent fresh supply of mineral nutrients (e.g. spring bloom in temperate waters, upwelling areas).
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The marine nitrogen cycle consists of complex microbial transformations which include the fixation of nitrogen, its assimilation, nitrification, anammox and denitrification. Some of these processes take place in deep water so that where there is an upwelling of cold waters, and also near estuaries where land-sourced nutrients are present, plant growth is higher. This means that the most productive areas, rich in plankton and therefore also in fish, are mainly coastal.
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Next to the Great Barrier Reef, the GSACUS and its ecosystem can be regarded as one of Australia's natural wonders. Due to its importance as a blue whale feeding and aggregation site, in 2002 the Bonney Upwelling was listed as critical habitat "requiring effective protection from user impacts"Australia. Department of Sustainability, Environment, Water, Population and Communities. National Oceans Office. South-east Regional Marine Plan: Implementing Australia’s Oceans Policy in the South-east Marine Region.
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Like Monterey Canyon to the north the canyon provides cold, nutrient-rich water to the surface during upwelling events. These nutrient-rich waters fuel the high primary productivity seen in Carmel and Monterey Bays, which in turn support the high diversity of life observed in the water and on land at Point Lobos. Point Lobos is one of only two places where the Monterey Cypress are native.C.Michael Hogan and Michael P. Frankis. 2009.
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Dusky dolphins at Kaikoura, New Zealand leaping off Kaikoura Dusky dolphins prefer cool, upwelling waters, as well as cold currents. They largely live in inshore waters and can be found up to the outer continental shelf and in similar zones in offshore islands. They can move over great distances (around 780 km), but have no well-defined seasonal migrations. However, dolphins off Argentina and New Zealand make inshore and offshore seasonal and diurnal movements.
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The average annual precipitation increases from about in the north to in the south. Fog is frequent along the coasts, especially in the upwelling cold- water areas. The sea has a warm cyclone current, forming part of the Kuroshio Current, which diverges near the western part of Japan and flows northward into the Yellow Sea at the speed of below . Southward currents prevail near the sea coast, especially in the winter monsoon period.
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In order for zooplankton to have a continuous food supply, the phytoplankton blooms must not occur too far apart. Pulses of upwelling in the Benguela system regularly have a duration of 10 days, an optimal period for biological production. It is estimated that the annual new production in the Benguela system is 4.7 × 10^13 gC/y, making the Benguela system 30 to 65 times more productive per unit area than the global ocean average.
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The Wieliczka Salt Mine (), in the town of Wieliczka, southern Poland, lies within the Kraków metropolitan area. From Neolithic times, sodium chloride (table salt) was produced there from the upwelling brine. The Wieliczka salt mine, excavated from the 13th century, produced table salt continuously until 2007, as one of the world's oldest operating salt mines. Throughout its history, the royal salt mine was operated by the Żupy Krakowskie (Kraków Salt Mines) company.
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Bartel, B., 2002. Magma dynamics at Taal Volcano, Philippines from continuous GPS measurements. Master's Thesis, Department of Geological Sciences, Indiana University, Bloomington, Indiana Surface deformation indicates magma upwelling: increased magma supply produces bulges in the volcanic center's surface. Gas emissions may be monitored with equipment including portable ultra-violet spectrometers (COSPEC, now superseded by the miniDOAS), which analyzes the presence of volcanic gases such as sulfur dioxide; or by infra-red spectroscopy (FTIR).
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Along with much of the central and northern California coast, Big Sur frequently has dense fog in summer. The summer fog and lack of precipitation both result from the North Pacific High's presence offshore during that season. The high pressure cell inhibits rainfall and generates northwesterly air flow. These prevailing summer winds from the northwest drive the ocean surface water slightly offshore (through the Ekman effect) which generates an upwelling of colder sub surface water.
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The resulting breccia is uniform in rock type and chemical composition. Lavas may also pick up rock fragments, especially if flowing over unconsolidated rubble on the flanks of a volcano, and these form volcanic breccias, also called pillow breccias. Within the volcanic conduits of explosive volcanoes the volcanic breccia environment merges into the intrusive breccia environment. There the upwelling lava tends to solidify during quiescent intervals only to be shattered by ensuing eruptions.
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In an attempt to explain the unprecedented and rapid spread of vegetation over dry land surfaces during the middle Paleozoic, Mark and Dianna McMenamin proposed the Hypersea Theory. Their Hypersea is a geophysiological entity consisting of eukaryotic organisms on land and their symbionts. By means of a process known as hypermarine upwelling, the expansion of Hypersea led to a dramatic increase in global species diversity and a one hundred-fold increase in global biomass.
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San Francisco is located only about seventy nautical miles north of Santa Cruz. The cool California Current offshore, enhanced by upwelling of cold sub-surface waters, often creates summer fog near the coast, and June 6, 1853, was no exception. As night approached, so did the fog. The captain of Carrier Pigeon, Azariah Doane, believed that the ship was far from shore, and so he gave the order to sail eastward toward the shore.
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Nitrification can then occur to convert the ammonium to nitrite and nitrate. Nitrate can be returned to the euphotic zone by vertical mixing and upwelling where it can be taken up by phytoplankton to continue the cycle. N2 can be returned to the atmosphere through denitrification. Ammonium is thought to be the preferred source of fixed nitrogen for phytoplankton because its assimilation does not involve a redox reaction and therefore requires little energy.
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Nitrate requires a redox reaction for assimilation but is more abundant so most phytoplankton have adapted to have the enzymes necessary to undertake this reduction (nitrate reductase). There are a few notable and well-known exceptions that include most Prochlorococcus and some Synechococcus that can only take up nitrogen as ammonium. The nutrients in the ocean are not uniformly distributed. Areas of upwelling provide supplies of nitrogen from below the euphotic zone.
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Nitrogen entering the euphotic zone is referred to as new nitrogen because it is newly arrived from outside the productive layer. The new nitrogen can come from below the euphotic zone or from outside sources. Outside sources are upwelling from deep water and nitrogen fixation. If the organic matter is eaten, respired, delivered to the water as ammonia, and re-incorporated into organic matter by phytoplankton it is considered recycled/regenerated production.
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These so-called "hotspots", for example Hawaii, are postulated to arise from upwelling diapirs with magma from the core–mantle boundary, 3,000 km deep in the Earth. Volcanoes are usually not created where two tectonic plates slide past one another. Sabancaya volcano erupting, Peru in 2017 Cordillera de Apaneca volcanic range in El Salvador. The country is home to 170 volcanoes, 23 which are active, including two calderas, one being a supervolcano.
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The occurrence of red tides in some locations appears to be entirely natural (algal blooms are a seasonal occurrence resulting from coastal upwelling, a natural result of the movement of certain ocean currents) while in others they appear to be a result of increased nutrient pollution from human activities.Lam CWY, Ho KC (1989) Red tides in Tolo Harbor, Hong Kong. In: Okaichi T, Anderson DM, Nemoto T (eds) Red tides. Biology, environmental science and toxicology.
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Wind shear also decreased, allowing Leslie to re-organize and strengthen into a hurricane at 1200 UTC on September 5. Six hours later, Leslie attained its maximum sustained wind speed of 80 mph (130 km/h). However, the slow movement of the storm caused upwelling - a process by which warm SSTs are replaced with colder waters. As a result, Leslie slowly began to weaken and fell to tropical storm intensity by early on September 8\.
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Soon afterwards, Trami lost its steering current and slowed as it is situated between two subtropical high pressure, an area called the pressure field of the saddle type. The typhoon's persistence over the same location for several days resulted in tremendous upwelling of cooler waters, with sea surface temperatures dropping from . The combined effect of cooler water and dry air resulted in significant weakening, and Trami dropping below super typhoon status late on September 25.
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Parallel to geological and geophysical measures (e.g. isotope ratios and seismic velocities) it is constructive to test hypotheses on computer based geodynamical models. A 3D numerical geodynamical model of the plume-crust coupling was capable of reproducing the lateral asymmetry of the EAR around the Tanzania craton. Numerical modeling of plume-induced continental break-up shows two distinct stages, crustal rifting followed by lithospheric breakup, and the upwelling between stages of an upper mantle plume.
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They are also found in the Western Block, indicating that the metamorphic events was a craton-wide event. Zhao, on the opposite, argued that based on the lithological evidences, for example, the Eastern and Western Blocks must have been formed in settings different from the central part 2.6 to 2.5 billion years ago. Therefore, they would have been separated at that time. The pluton upwelling may explain the metamorphic event 2.5 billion years ago.
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The marine nitrogen cycle consists of complex microbial transformations which include the fixation of nitrogen, its assimilation, nitrification, anammox and denitrification. Some of these processes take place in deep water so that where there is an upwelling of cold waters, and also near estuaries where land-sourced nutrients are present, plant growth is higher. This means that the most productive areas, rich in plankton and therefore also in fish, are mainly coastal.
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The upper photic zone of the ocean is filled with particle organic matter (POM) and is quite productive, especially in the coastal areas and the upwelling areas. However, most POM is small and light. It may take hundreds, or even thousands of years for these particles to settle through the water column into the deep ocean. This time delay is long enough for the particles to be remineralized and taken up by organisms in the food webs.
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It curved north while rapidly succumbing to the effects of ocean upwelling, making landfall on Baja California Sur as a minimal tropical storm early on June 15\. On the next day, land interaction and increasing wind shear caused Bud to degenerate to a remnant low, and Bud dissipated completely on June 16\. Bud prompted the issuance of multiple watches and warnings for Baja California Sur and Western Mexico. Additionally, Bud caused one death in Mexico City.
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It does this by producing warm core eddies, which allow the Tasman Seas to have a large biodiversity. The most southern tip of the EAC can produce these Eddies by wind currents. As instabilities in the current develop due to a westward Tasman Front, the meander pinches off to form eddies at a rate of once or twice per year. The EAC has nutrient poor water, however it does cause upwelling in places along the coast line.
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Exceptions to this rule are areas of permanently enriched nutrients such as upwelling areas and coastal watersheds. In the nutrient-depleted areas of the oceans, such as the central gyres, Synechococcus is apparently always present, although only at low concentrations, ranging from a few to 4×10³ cells per ml. Vertically Synechococcus is usually relatively equitably distributed throughout the mixed layer and exhibits an affinity for the higher-light areas. Below the mixed layer, cell concentrations rapidly decline.
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At issue are the current plate configuration and rate of subduction but Silverthrone's chemistry indicates that Silverthrone is subduction related. The Cascadia subduction zone is a long convergent plate boundary that separates the Juan de Fuca, Explorer, Gorda and North American Plates. Here, the oceanic crust of the Pacific Ocean sinks beneath North America at a rate of per year. Hot magma upwelling above the descending oceanic plate creates volcanoes, each of which erupts for a few million years.
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The upwelling region south of Madagascar, an important conveyor of nutrients for marine wildlife and fisheries off the coast of Madagascar, was found to be primarily wind-driven, but also influenced by a poleward eastern boundary flow coming from the Mozambique Channel. The system was subsequently identified as a previously unrecognized current. The current was likely not recognized as such before 2018 because the oceanic region in question has only been subject to relatively light oceanographic sampling so far.
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They measure radiances in various wavelength bands. Since 1978 microwave sounding units (MSUs) on National Oceanic and Atmospheric Administration polar orbiting satellites have measured the intensity of upwelling microwave radiation from atmospheric oxygen, which is related to the temperature of broad vertical layers of the atmosphere. Measurements of infrared radiation pertaining to sea surface temperature have been collected since 1967. Satellite datasets show that over the past four decades the troposphere has warmed and the stratosphere has cooled.
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Cymbula adansonii commonly inhabit intertidal regions of shores. Their habitat zones are located near the western coastline of Namibia, Angola, and South Africa. Geographic information was documented by Wilhelm Dunker in the coastal cities of Swakopmund and Langstrand. The presence of nutrient-rich upwelling across the western regions of Africa is a main factor behind this species’ distribution. As a result of this the western coast has a greater proportion of productivity in comparison to the continent’s other coastlines.
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Downwelling is the process of accumulation and sinking of higher density material beneath lower density material, such as cold or saline water beneath warmer or fresher water or cold air beneath warm air. It is the sinking limb of a convection cell. Upwelling is the opposite process and together these two forces are responsible in the oceans for the thermohaline circulation. The sinking of cold lithosphere at subduction zones is another example of downwelling in plate tectonics.
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A very gentle temperature gradient from the equator to the poles meant weaker global winds, which drive the ocean currents, resulted in less upwelling and more stagnant oceans than today. This is evidenced by widespread black shale deposition and frequent anoxic events. Sediment cores show that tropical sea surface temperatures may have briefly been as warm as , warmer than at present, and that they averaged around . Meanwhile, deep ocean temperatures were as much as warmer than today's.
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This upwelling in turn results in foggy conditions throughout the summer, with high temperatures commonly in the 50s and low 60s. Yet just a few miles inland the temperatures may be up to 25 degrees warmer in the summer and fall. Winter high temperatures average in the low 40s to mid-50s, with lows in the mid-30s to lower 40s. Temperatures infrequently dip below in the winter, and nearly as infrequently climb above in the summer and fall.
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The waters off the western coast seem to have featured upwelling and low-oxygen. The holotype was identified in the upper level of the Kuldana Formation at Locality 9209, which features green mud and silt as well as a bed of marine shells, including marine snails (such as Turritella) and bivalves. It was likely a coastal area. A redbed underlies this layer, which is followed by grey, green, and purple freshwater mud, silts, sandstones, and limestone.
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The system turned northwest around the periphery of a ridge, tracking into a region of low ocean heat content that prompted cold water upwelling. Simon rapidly weakened to a tropical storm early on October 6 before gradually degenerating to a remnant area of low pressure around 00:00 UTC on October 8\. The post-tropical cyclone turned east and moved ashore Baja California Sur several hours later before dissipating over rugged terrain by 06:00 UTC the next day.
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Subaqueous fumaroles are the probable cause of active upwelling that occurs at the two eastern lakes. The lakes have been a source of minor phreatic eruptions in historical time. The summit of the compound 1639-m-high Kelimutu volcano is elongated two km in a WNW-ESE direction; the older cones of Kelido and Kelibara are located respectively three km to the north and two km to the south. The scenic lakes are a popular tourist destination.
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Seasonal upwelling transports colder, more dense bottom waters up to the surface along the coastline due to the dominant southward wind stress on the coastal waters. The upwelled water brings nutrients up to the surface euphotic zone. Summer surface temperatures of the water range from approximately 7 °C on the coastline up to 14 °C along the outer edge of Heceta Bank. At the same time, high-density bottom water is advected over the bank by northward bottom currents.
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Chlorophyll a (Chl-a) concentrations in the Heceta Bank region are consistently higher than those in the surrounding shelf. These elevated values are the result of the outcropping of nutrient-rich water from the halocline. During spring, a coastal upwelling jet is located inshore of Heceta Bank and moves offshore during summer. Two immediate consequences of the invasion of subarctic water off Oregon are an increase in primary production and an increase in water column and benthic respiration.
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On the coast, the upwelling of the cold Benguela current gives rise to dense ocean fogs (called cassimbo by the Angolans) for much of the year. The winds blow from land to sea, rainfall rarely exceeds annually and the climate is highly inhospitable. There is a constant, heavy surf on the beaches. In the days before engine-powered ships and boats, it was possible to get ashore through the surf but impossible to launch from the shore.
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A study done at the Mahoney Lake suggested that purple sulfur bacteria contributes to the recycling of the inorganic nutrient, phosphorus. The upwelling of purple sulfur bacteria into the top layer of water creates a source of bound phosphorus, and phosphatase activity releases this phosphorus into the water. The soluble phosphorus is then incorporated into heterotrophic bacteria for use in developmental processes. In this way, purple sulfur bacteria participates in the phosphorus cycle and minimizes nutrient loss.
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The first noted occurrence of the unusual toxic bloom of pseudo-nitzschia species on the French Atlantic coast happened in 1995. Pseudo-nitschia species have been observed in the waters every spring and autumn since 2006, but in low quantities. 2010 was an outlier year in which there was a larger bloom most likely caused by upwelling and nutrient runoff from a large storm. Additionally, this was the first year the species P. australis had been observed.
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Blooms are the result of a nutrient that the particular algae need being introduced to the local aquatic system. This growth-limiting nutrient is typically nitrogen or phosphorus, but can also be iron, vitamins, or amino acids. There are several mechanisms for the addition of these nutrients in water. In the open ocean and along coastlines, upwelling from both winds and topographical ocean floor features can draw nutrients to the photic, or sunlit zone of the ocean.
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The hurricane's slow motion resulted in tremendous upwelling of cooler water, resulting in a period of weakening. Blanca gradually recovered from this and briefly regained Category 4 status on June 6 as it moved generally northwest toward the Baja California peninsula. Cooler waters and increased shear again prompted weakening on June 7 and the system struck Baja California Sur on June 8 as a weak tropical storm. It quickly degraded to a depression and dissipated early the next day.
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The Bodega Head area contains one of the most persistent and important upwelling plumes along the entire California coast and provides for significant downstream larval dispersal, resulting in an area of high abundance and natural diversity. The area provides important habitat for nearshore, shelf, and deeper nearshore rockfishes such as lingcod, kelp greenling, and cabezon, as well as a diversity of benthic invertebrates. Murres, auklets, guillemots, and marine mammals also depend on the habitat and forage fishes found here.
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Blakiston's fish owls are easily amongst the most aquatically-based owls in the world. Blakiston's fish owl occurs in dense old-growth forest near waterways or wooded coastlines. The species requires cavernous old-growth tree cavities for suitable nest sites and stretches of productive rivers that remain at least partially unfrozen in winter. In the frigid northern winters, open water is found only where the current is sufficiently fast-flowing or there is an upwelling of warm spring water.
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As a result of its slow motion, the storm caused significant upwelling, leading to a marked decrease in convection, and weakening accordingly. On September 11, Nate moved ashore Mexico as a tropical storm, producing several inches of rainfall and damaging several hundred structures. Ten oil rig workers went missing; seven were rescued, but one died of an unknown cause, and three other bodies were later recovered. In Veracruz, a boy was killed after being struck by lightning.
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The sanctuary serves as a breeding ground for migratory marine mammals, birds, and fish. The prevailing California Current flows southward along the coast, causing an upwelling of nutrient-rich water that provided the foundation for the area's marine ecosystem. Sanctuary regulations prohibit extraction of hydrocarbons (oil, natural gas), the removal of benthic (bottom-dwelling) organisms, discharge of wastes, and removal of cultural resources. Recreational SCUBA diving is not recommended in the sanctuary due to depth and currents.
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On average there is 0.07±0.04 nmol Fe kg−1 at the surface (<200 m) and 0.76±0.25 nmol Fe kg−1 at depth (>500 m). Therefore, upwelling zones contain more iron than other areas of the surface oceans. Soluble iron in ferrous form is bioavailable for utilization which commonly comes from aeolian resources. Iron primarily is present in particulate phases as ferric iron, and the dissolved iron fraction is removed out of the water column by coagulation.
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They can be found in tidal pools, fjords and estuaries, near sandy shores and rocky coastlines, around coral reefs and on or above the continental shelf. Coastal fish include forage fish and the predator fish that feed on them. Forage fish thrive in inshore waters where high productivity results from upwelling and shoreline run off of nutrients. Some are partial residents that spawn in streams, estuaries and bays, but most complete their life cycles in the zone.
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In 1953, Robert S. Dietz and his colleagues first identified the swell behavior. It was suggested that the cause was mantle upwelling. Later work pointed to tectonic uplift, caused by reheating within the lower lithosphere. However, normal seismic activity beneath the swell, as well as lack of detected heat flow, caused scientists to suggest dynamic topography as the cause, in which the motion of the hot and buoyant mantle plume supports the high surface topography around the islands.
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Here, the oceanic crust of the Pacific Ocean sinks beneath North America at a rate of per year. Hot magma upwelling above the descending oceanic plate creates volcanoes, and each individual volcano erupts for a few million years. The subduction zone has existed for at least 37 million years, and has created a line of volcanoes called the Cascade Volcanic Arc which stretches over along the subduction zone. Several volcanoes in the arc are potentially active.
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Wrinkle ridges can be viewed as the purple fill in figure C. These outcrops dominate the low-lying region and are marked with yellow lines that represent major trends. Figure D shows the distribution of fracture belts and their trends in black. The likely cause of these trends is due to mantel upwelling at Beta Regio to the west. The trend of these figures can be directly related to radiating fractures and grabens, interpreted as underlying dyke swarms.
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Selenium is made available to the food chain through four oxidation and methylation processes. The first process is oxidation and methylation of inorganic and organic selenium by plant roots and microorganisms. The second process is biological mixing and associated oxidation of sediments from the burrowing of benthic invertebrates and feeding of fish and wildlife. The third process is represented by physical movement and chemical oxidation from water circulation and mixing, such as current, wind, precipitation, and upwelling.
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Submarine eruptions may produce seamounts which may break the surface to form volcanic islands and island chains. Submarine volcanism is driven by various processes. Volcanoes near plate boundaries and mid-ocean ridges are built by the decompression melting of mantle rock that rises on an upwelling portion of a convection cell to the crustal surface. Eruptions associated with subducting zones, meanwhile, are driven by subducting plates that add volatiles to the rising plate, lowering its melting point.
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The Musgrave orogeny was one of three Mesoproterozoic orogenic events affecting the Musgrave Province in Central Australia between 1.22 and 1.12 billion years ago. Earlier, 1.29 billion years ago the Musgrave Province formed as the North, West and South Australian cratons converged. The granites of the Pitjantjatjara Supersuite intruded during the event at high temperatures above 1000 degrees Celsius. The event is interpreted as an intracontinental orogeny due to significant upwelling of heat and material from the mantle.
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The lower course through Vandenberg AFB has a perennial flow, in part because of irrigation tailwater, but primarily because of a geologic rift at Barka Slough which causes an upwelling. The principal crops grown within its watershed are vegetables in the flat fields, and winegrapes in the transitional upland slopes. All are irrigated from groundwater aquifer resources. In 1996 almost all of the water supply used by Vandenberg AFB was pumped from the San Antonio Aquifer.
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The Point Vicente Interpretive Center offers recreational and educational opportunities to the public and is a famous spot for observing migrating whales from shore, due in part to its high elevation. This area has all the right conditions to attract large whale species: steep, deep drop-off coupled with robust upwelling. Nearby Point Vicente Lighthouse is a cylindrical style lighthouse constructed in 1926. It is home to a third order Fresnel lens which is still active.
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Eastern boundary currents are relatively shallow, broad and slow-flowing. They are found on the eastern side of oceanic basins (adjacent to the western coasts of continents). Subtropical eastern boundary currents flow equatorward, transporting cold water from higher latitudes to lower latitudes; examples include the Benguela Current, the Canary Current, the Humboldt Current, and the California Current. Coastal upwelling often brings nutrient-rich water into eastern boundary current regions, making them productive areas of the ocean.
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Manado, Indonesia, 11–14 May 2009 Declarations. A report from NOAA scientists published in the journal Science in May 2008 found that large amounts of relatively acidified water are upwelling to within four miles of the Pacific continental shelf area of North America. This area is a critical zone where most local marine life lives or is born. While the paper dealt only with areas from Vancouver to northern California, other continental shelf areas may be experiencing similar effects.
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Umbrina canariensis occursin the western Mediterranean, as far east as the Sicilian Channel and northeastern Atlantic to the Canary Islands, along most of the western African coastline from Gibraltar to central Namibia. It is uncommon in northern Namibia and absent off southern Namibia and the west coast of South Africa caused by the cold Benguela Upwelling System. In the Western Indian Ocean it occurs from False Bay in Western Cape to Mozambique, it has also been reported from Pakistan.
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Indian Acad. Sci (Earth Planet. Sci.) 11: 227-236 producing a dominant period of northeasterly tradewinds known as the Panamá Jet, which results in a reversal of water circulation and becomes a cyclonic gyre with a coastal current flowing to the north. Upwelling develops in the Gulf of Panama during the dry season when northeast tradewinds from the Caribbean blow over to the Pacific through a physiographic gap in the central mountain range which divides the Isthmus.
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N. bolini is found in the Atlantic Ocean and the Mediterranean Sea. Its range extends in the North Atlantic from about 50°N to about 35°N, mainly to the east of 50°W. However, there are some separate areas where it is found, these being around the Canary Islands and off the coast of Mauritania where there is an area of upwelling water. It also occurs in the deep parts of both the eastern and western Mediterranean Sea.
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This extra tube segregates the flow into a central cold downcomer and an upwelling outer flow of heated water and boiling steam. In the thimble tube, there is no such segregation and so boiling is a random process with flow back and forth along the tube. The thimble tube boiler was developed after experiments by Thomas Clarkson and is still firmly associated with the Clarkson firm as a maker. Other makers also produced them in smaller quantities.
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It executed a clockwise loop to the west, weakening due to upwelling upon reaching its path again. Jeanne encountered favorable conditions as it continued westward, and it reached major hurricane status before crossing the northern Bahamas on September 25. The next day, it struck Martin County, Florida in nearly the same location as Hurricane Frances just weeks before. Jeanne weakened over land while turning the northwest, deteriorating to tropical depression status over Georgia on September 27.
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The cyclone passed west of Réunion on February 27, after beginning a steady motion to the south-southwest. By that time, Gamede had weakened due to upwelling cooler waters, and later weakened further due to stronger wind shear. On March 2, the MFR reclassified Gamede as an extratropical cyclone, and the agency tracked the storm for four more days as the circulation again stalled before drifting westward. Cyclone Gamede passed near St. Brandon, where its wind gusts damaged a few windows.
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Gershwin has worked with and for a range of scientific organisations, including CSIRO. She developed a system to predict blooms of the hazardous Irukandji jellyfish in north Queensland. She led a team that discovered that the blooms coincide with the blooming of salps, and that these were prompted by upwelling after the dying down of trade winds. In December 2017 Gershwin's team refined a model for the early warning forecasting systems for irukandjis, with water testing off Cairns' northern beaches.
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Ignacio weakened quickly on September 18, probably due to the combined effects of the storm's close proximity to land and persistence of waters likely cooled by upwelling. Strong winds aloft, shearing Ignacio from the southwest, might have contributed to the weakening as well. Ignacio was downgraded to a tropical depression on September 19 and became a remnant low later that day. The remnants of Ignacio, identified on satellite imagery as occasional flare-ups of convection, moved west-southwestwards over the next two days.
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The colonies in woodland settings are found under partial canopy in an open, primarily herbaceous understory shape. The Monterey Peninsula and northern Big Sur areas are influenced by a marine climate that is pronounced due to the upwelling of cool water from the Monterey submarine canyon. Rainfall is 40 to 50 centimeters per year, but summer fog drip is a primary source of moisture for Yadon's Piperia and other plants that would otherwise not be able to persist with such low precipitation.
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A superswell is a large area of anomalously high topography and shallow ocean regions. These areas of anomalous topography are byproducts of large upwelling of mantle material from the core–mantle boundary, referred to as superplumes. Two present day superswells have been identified: the African superswell and the South Pacific superswell. In addition to these, the Darwin Rise in the south central Pacific Ocean is thought to be a paleosuperswell, showing evidence of being uplifted compared to surrounding ancient ocean topography.
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At Bodega Marine Laboratory (near Bodega Head), Hill and colleagues studied the effect of ocean acidification in the natural laboratory of the California continental margin. Here, upwelling of carbon dioxide-rich water seasonally decreases the pH in local marine environments. One theory about this region is that local fauna would be well adapted to acidic (low pH) water. Hill and colleagues have shown that acidic waters have an adverse impact on growth characteristics of the protozoan zooplankton foraminifera, oysters, and mussels.
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Therefore, the predators of the targeted fish will begin to die off, and there will not be as many of them to feed the predators above them. This system continues throughout the entire food chain, resulting in a possible collapse of the ecosystem. It is possible that the ecosystem may be restored over time, but not all species can recover from events such as these. Even if the species can adapt, there may be a delay in the reconstruction of this upwelling community.
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Processes of Coastal Upwelling and Carbon Flux in the Cariaco Basin. Deep-Sea Research Part II. Special Issue: Views of Ocean Processes from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) Mission: Volume 2 - Edited by D. A. Siegel, A. C. Thomas and J. Marra. Vol 51/10-11 pp 927–943. This naturally occurring anoxic basin allows for sediments to be deposited without bioturbation, forming varves of alternating light and dark color, which correspond to the dry or rainy season.
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By alongshore winds, upwelling current flows to the coast. Near the equator, the East African Coast Current (EACC) flows northward across the equator. The southern Somali Current flows northward as an extension of the EACC from south to the 3-4°N. Northeastward current (Jun-Sep, Summer Monsoon): The Somali Current begins developing its strength from mid-May with the summer monsoon onset, and current velocities rapidly grow to the maximum until June and September with the southwest monsoon blowing.
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Artificial reefs tend to develop in more or less predictable stages. First, where an ocean current encounters a vertical structure, it can create a plankton-rich upwelling that provides a reliable feeding spot for small fish such as sardines and minnows, which draw in pelagic predators such as tuna and sharks. Next come creatures seeking protection from the ocean's lethal openness--hole and crevice dwellers such as grouper, snapper, squirrelfish, eels and triggerfish. Opportunistic predators such as jack and barracuda also appear.
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Shortly after peaking in intensity, the cyclone rapidly weakened in response to increasing wind shear, drier air and decreasing sea surface temperatures due to upwelling as it turned northwestwards around the edge of a subtropical ridge. By 18:00 UTC on October 27, Seymour had weakened to a tropical storm, shortly before degenerating into a remnant low early the next day. The low continued to drift northwards before dissipating on October 30 about west of Puerto Cortes, Baja California Sur, Mexico.
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The current brings nutrient rich water along the coast of Norway, and with it rich fisheries of cod, herring, and capelin. Wind driven upwelling along the Strait of Skagerrak brings abundant nutrients to the surface which are then carried along the coastline. Norway has one of the biggest fishing industries in the world, harvesting an average of 3 million metric tons of fish each year. The Norwegian coast is also an important spawning ground for many of the commercial fishes.
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Ocean-plate creation at upwellings, spreading and subduction are well accepted fundamentals of plate tectonics, with the upwelling of hot mantle materials and the sinking of the cooler ocean plates driving the mantle convection. In this model, tectonic plates diverge at mid-ocean ridges, where hot mantle rock flows upward to fill the space. Plate-tectonic processes account for the vast majority of Earth's volcanism. Beyond the effects of convectively driven motion, deep processes have other influences on the surface topography.
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The simplest interpretation is that zones are sites of atmospheric upwelling, whereas belts are manifestations of downwelling. When air enriched in ammonia rises in zones, it expands and cools, forming high and dense clouds. In belts, however, the air descends, warming adiabatically as in a convergence zone on Earth, and white ammonia clouds evaporate, revealing lower, darker clouds. The location and width of bands, speed and location of jets on Jupiter are remarkably stable, having changed only slightly between 1980 and 2000.
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In both the Atlantic and Pacific oceans, a tongue of cold surface water usually extends westward along the equator from the continental margins. These "cold tongues" consist of water upwelling from the ocean depths, and are surrounded by warmer surface water in both hemispheres. The temperature difference between the cold tongues and the surrounding warm water is largest during the southern hemisphere winter. The Pacific cold tongue is considerably stronger than the Atlantic one, and has a major influence on global climate patterns.
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Coral reefs, mangrove forests and seagrass meadows as well as rivers, estuaries, coastal waters and upwelling areas comprise some of the most important tropical coastal ecosystems. They are in close physical, biological and geochemical interaction as transitional areas between land and water and host high biodiversity. However, climate change, overexploitation of resources, population increase, and urbanisation profoundly alter these ecosystems. These developments impact social-ecological and socio-economic structures and confront society with the need for sustainable management of coastal ecosystems.
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The water in the vicinity of Asilomar State Beach is known for rip tides and unpredictable surf. The water is cold compared to other beaches in the Monterey area, due to its exposure to the open ocean and the upwelling of cold water from nearby Monterey Canyon, which funnels the icy water right to shore at this location. Despite the cold water the area is popular with surfers and visitors from around the world. The beach does not feature a bathroom facility.
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In addition, a dropsonde recorded winds of while descending to the surface, the highest dropsonde wind speed recording in a hurricane at the time. Around the time it peaked in intensity, Lenny's forward speed decreased in response to light steering currents between two ridges. Despite favorable conditions for strengthening, the hurricane weakened as it turned to an eastward drift, possibly due to the upwelling of cooler waters. Late on November 18, Lenny's eye moved over Saint Martin with winds of .
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Mantle upwelling thinned the crust in the Jurassic. In Mississippi, the Smackover Limestone covered over earlier evaporite deposits. A complex stratigraphic sequence formed during the Cretaceous, with the reef limestones, anhydrite and sandstones of the Rodessa Formation, Mooringsport Formation, Paluxy Formation, Gordo Formation and Coker Formation, overlain by the Eutaw Group, Austin Chalk, Selma Chalk and numerous thin marl, chalk and sandstone layers. The Richton Salt Dome was briefly famous in the early 1980s as a proposed site for US nuclear waste disposal.
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1930, Radioactivity and Earth movements. Geological Society of Glasgow Transactions, 18, pp.559-606. However, some studies have shown that the upper mantle (asthenosphere) is too plastic (flexible) to generate enough friction to pull the tectonic plate along. Moreover, mantle upwelling that causes magma to form beneath the ocean ridges appears to involve only its upper 400 km (250 mi), as deduced from seismic tomography and from observations of the seismic discontinuity in the upper mantle at about 400 km (250 mi).
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An oceanic plate is added to by upwelling (left) and consumed at a subduction zone (right). Mantle convection is the slow creeping motion of Earth's rocky mantle caused by convection currents carrying heat from the interior of the earth to the surface. It is one of 3 driving forces that causes tectonic plates to move around the Earth's surface. The Earth's surface is divided into a number of tectonic plates that are continuously being created and consumed at their opposite plate boundaries.
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Mars is considerably smaller than Earth and Venus, and there is evidence for ice on its surface and in its crust. In the 1990s, it was proposed that Martian Crustal Dichotomy was created by plate tectonic processes. Scientists today disagree, and think that it was created either by upwelling within the Martian mantle that thickened the crust of the Southern Highlands and formed Tharsis or by a giant impact that excavated the Northern Lowlands. Valles Marineris may be a tectonic boundary.
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Point Arena is one of the major upwelling zones along the West coast of the U.S., which means it is a source of nutrients for fish and wildlife. An unusually scenic spot, Sea Lion Cove is an abalone nursery that also hosts many other invertebrate communities. Many of these populations have become vulnerable due to the recent opening of public access to this site. The Sea Lion Cove SMCA contributes to the protection of fragile abalone populations and the intertidal ecosystem.
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The icy Benguela and the warm, south-flowing Agulhas current do not meet off the Cape of Good Hope (see diagram on the right, above), but there is a body of water off the South African south coast, east and particularly west of Cape Agulhas that consists of eddies from both currents, so that off-shore water temperatures along the south coast of Africa vary chaotically.The red areas show major upwelling areas. The Benguela Current is on the southwest coast of Africa.
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According to Mircea Eliade, the Middle Ages witnessed "an upwelling of mythical thought" in which each social group had its own "mythological traditions".Eliade, Myths, Rites, Symbols, vol. 1, 82 Often a profession had its own "origin myth" which established models for members of the profession to imitate; for example, the knights tried to imitate Lancelot or Parsifal. The medieval trouveres developed a "mythology of woman and Love" which incorporated Christian elements but, in some cases, ran contrary to official church teaching.
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The sea life activity both surface and sub- surface varies considerably as either deep water upwelling brings cold water into the Bay, or warm water eddies over from the Agulhas Indian Ocean current offshore. A distinctive flower-shaped sea shell called a pansy shell is endemic to this part of the coast, and is used as the symbol representing the town. Looking for these shells on the beach at low tide is a popular activity amongst visitors and locals alike.
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Harbor seal skull (Phoca vitulina) Adult phocids vary from in length and in weight in the ringed seal to and in land-based members of the Carnivora, although they retain powerful canines. Some species lack molars altogether. The dental formula is: While otariids are known for speed and maneuverability, phocids are known for efficient, economical movement. This allows most phocids to forage far from land to exploit prey resources, while otariids are tied to rich upwelling zones close to breeding sites.
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A process similar to seafloor spreading has been proposed to explain the presence of the concentric stripes around the Martian south pole. The process is that of a single large mantle plume rising in one hemisphere and downwelling in the opposite hemisphere. In such a process, new crust produced would be emplaced in concentric circles spreading radially from a single upwelling point, consistent with the pattern observed on Mars. This process has also been invoked to help explain the Martian hemispheric dichotomy.
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This second model describes the upwelling of a mantle flow (plume) that accommodates the formation of crustal thickening by magmatic underplating and volcanic activities associated with the thin lithosphere. Planetary scientists that support this model identify two categories of extensional structures: long- narrow graben, referred to as a ribbons, and more widely spaced graben. The sequence of formation for these structures is still debatable. Some group of scientists believed that the ribbons were formed first, followed later on by the wide spaced graben.
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The CGSN is made up of two coastal arrays and four global arrays. Coastal arrays provide sustained, adaptable access to complex coastal systems. Coastal arrays extend from the continental shelf to the continental slope, allowing scientists to examine coastal processes including upwelling, hypoxia, shelf break fronts, and the role of filaments and eddies in cross-shelf exchange. Technologies that gather data in the coastal region include moored buoys with fixed sensors, moored vertical profilers, seafloor cables, gliders and autonomous underwater vehicles.
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The geothermal structure in a subduction zone determines the melting rate of subduction slab and asthenosphere. The change in isotherm structure may have significant impact on the intensity of magmatism. Some factors may contribute to the change in geothermal structure: a) the change in convergence velocity of two plates in subduction zone; b) the dipping angle of subduction slab; c) the amounts of subducted low temperature materials (water and oceanic sediments); d) the mantle/asthenosphere upwelling event (slab window/slab breakoff).
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Circumferential ridges and graben are also highly reflective to radar, and therefore, easily observed around the Sappho Patera depression. These concentric features formed after Irnini Mons lost the high pressure dynamic support from the mantle upwelling due to the lack of overlying flows. The presence of circumferential structures along a shallow depression on Irnini Mons' summit is a characteristic of coronae on Venus. The presence of corona-like features suggest two possible theories for interpretation of how Irnini Mons developed.
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Heat flow at passive margins changes significantly over its lifespan, high at the beginning and decreasing with age. In the initial stage, the continental crust and lithosphere is stretched and thinned due to plate movement (plate tectonics) and associated igneous activity. The very thin lithosphere beneath the rift allows the upwelling mantle to melt by decompression. Lithospheric thinning also allows the asthenosphere to rise closer to the surface, heating the overlying lithosphere by conduction and advection of heat by intrusive dykes.
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Halemaʻumaʻu, then a small upwelling in the caldera floor, was topped by a lava lake that then drained, before refilling again, forming an enormous lava lake and nearly reaching the top edge of the caldera before draining once more. This activity eventually gave way to the construction of Mauna Iki, building up the large lava shield on the volcano's southwest rift zone over a period of eight months. The eruption also featured concurrent rift activity and a large amount of lava fountaining.
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Development of the Bransfield Rift, depicting trench rollback and upwelling of displaced mantle material. The last and most recent stage in the evolution of the Antarctic Peninsula subduction zone is the opening of the Bransfield Rift, creating the Bransfield back-arc basin from the Oligocene to the present day. This basin separates the inner, older magmatic arc (mainland Antarctic Peninsula) from the outer, younger magmatic arc (South Shetland Islands). Alkaline and tholeiitic volcanic activity is associated with this rifting event.
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The geophysical method of seismic tomography is a suitable tool to investigate Earth's subsurface structures deeper than the crust. It is an inverse problem technique that models which are the velocities of the inner Earth that reproduce the seismographic data recorded all around the world. Recent improvements of tomographic Earth models of P-wave and S-wave velocities suggest that a superplume upwelling from the lower mantle at the northeastern EAR feeds plumes of smaller scale into the upper mantle.
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Fertilisation is internal, with clusters of eggs being laid on rocks and guarded by the male. The larvae are planktonic in the open sea and metamorphosis into juvenile fish probably occurs at times when the upwelling of nutrient-rich water occurs along this coastline. If conditions deteriorate in the pool inhabited by the fluffy sculpin when the tide is out, it is able to leave the water and breathe air. It is less tolerant of adverse conditions than the tidepool sculpin.
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There is diveable reef off the Mzamba river just outside the MPA, and further south off the Mnyameni River in the northern controlled area, and off the Sikombe river at the border of the restricted zone. Further south there is a large area of reef off the Mtentu River inside the no-take zone, and off the Mkhambati reserve near Mgwegwe. Further south the visibility is often poor due to upwelling from an eddy between Port St Johns and Waterfall bluff.
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Thermobarometric data also indicate a magma origin depth of . Beneath Tuzgle, a high seismic attenuation plume rises from an earthquake cluster at depth up to the volcano and is probably linked to asthenospheric upwelling. In the ground beneath Tuzgle, seismic tomography has found a thick layer of low velocity, probably linked to a lower density of the rock, at a depth of . Magnetotelluric analysis has found several deep () conductive layers and one shallow one, possibly formed by the aquifers in the area.
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Asia blocks heat export and prevents the ventilation of the Indian Ocean thermocline. That continent also drives the Indian Ocean monsoon, the strongest on Earth, which causes large-scale seasonal variations in ocean currents, including the reversal of the Somali Current and Indian Monsoon Current. Because of the Indian Ocean Walker circulation there are no continuous equatorial easterlies. Upwelling occurs near the Horn of Africa and the Arabian Peninsula in the Northern Hemisphere and north of the trade winds in the Southern Hemisphere.
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The water clouds are assumed to generate thunderstorms in the same way as terrestrial thunderstorms, driven by the heat rising from the interior. The orange and brown coloration in the clouds of Jupiter are caused by upwelling compounds that change color when they are exposed to ultraviolet light from the Sun. The exact makeup remains uncertain, but the substances are thought to be phosphorus, sulfur or possibly hydrocarbons. These colorful compounds, known as chromophores, mix with the warmer, lower deck of clouds.
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Thereafter, a blocking pattern over Atlantic Canada caused Leslie to drift for four days. Late on September 5, Leslie was upgraded to a hurricane, shortly before strengthening to its peaking intensity with winds of 80 mph (130 km/h) and a minimum barometric pressure of 968 mbar (28.6 inHg). However, due to its slow movement, the storm caused upwelling, which decreased ocean temperatures, weakening Leslie to a tropical storm on September 7. The storm drifted until September 9, when it accelerated while passing east of Bermuda.
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The shearwaters breed only within the Cape Verde Islands. The largest colonies are on the islands of Brava, Branco and Raso, though the species also breeds in smaller numbers on other islands in the archipelago. Though their pelagic distribution and movements are not well known, they are regularly seen around the islands in the breeding season. After the breeding season they disperse and may sometimes be seen in the upwelling zone in Senegalese waters, where about 10% of the population has been recorded in October.
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The coastal plain has a Mediterranean climate but is affected by the upwelling cold Canary Current close off-shore; this gives it wet winters and warm summers. The Rif Mountains rise to and have mountain ridges cut by gorges and valleys and clad with forests of Atlas cedar, cork oak, holm oak, and Moroccan fir. The climate here is Mediterranean with up to of precipitation, hot summers and mild winters. The Middle and High Atlas mountains have a more continental climate, with colder winters and hotter summers.
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Carleton failed to capitalize on this upwelling of Loyalist support by using them for a relief expedition against the besieging Americans. After several weeks of inaction by Carleton, the rural men drifted away, called by the demands of home and harvest. (Carleton did take advantage of the moment to order the arrest of Thomas Walker, a Montreal merchant who was openly pro-American and had been reporting to the Americans.)Stanley, pp. 48–49 The conditions for the Americans constructing the siege works were difficult.
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This can be thought of as analogous to a rug on a table with little friction: when part of the rug is off of the table, its weight pulls the rest of the rug down with it. However, the Mid-Atlantic ridge itself is not bordered by plates that are being pulled into subduction zones, except the minor subduction in the Lesser Antilles and Scotia Arc. In this case the plates are sliding apart over the mantle upwelling in the process of ridge push.
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The geologic Toluca Lake is a body of water located near the district’s southeastern boundaries. The historic natural lake was fed by springs of upwelling groundwater from the Los Angeles River and San Fernando Valley subterranean aquifers. Late 19th and 20th century L. A. DWP well extraction and 1930s concrete river channelization lowered the water table, and currently community wells at the lake’s edges maintain the water level. The bottom of the lake is surfaced with four inches (102 mm) of asphalt concrete to prevent seepage.
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Investment prospectus and technical specifications, p.105 The system consists of six circular bags that are made of a heavy-gauge plastic installed in a steel frame floating at the surface and held in place by anchors in the same way as the net-pens. Electrical upwelling pumps continuously pump fresh seawater into the bags, and portable liquid oxygen tanks are used to provide oxygen to the cultured fish. A specially designed outlet is used to exit the waste-water and entered the marine environment untreated.
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The NHC had anticipated the movement to be part of a small loop in the Gulf of Honduras, although the agency noted continued uncertainty. Steadily deteriorating, Mitch weakened below major hurricane intensity late on October 28, due to land interaction, upwelling, and possibly an eyewall replacement cycle. On October 29, the hurricane made landfall in Honduras, east of La Ceiba, with winds of 80 mph (130 km/h). Despite being over land, the NHC continued to predict a turn to the north, which would allow for restrengthening.
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Unusually for the Pennines, rock of igneous origin (the Whin Sill) contributes to the surface geology and scenery of Teesdale. Around 295 million years ago upwelling magma spread through fissures and between strata in the earlier Carboniferous Limestone country rock. As it cooled (an event which is believed to have lasted 50 years) the rock contracted and caused itself to split into vertical columns. The heating of the limestone above the rock also caused it to be turned into a crumbly marble known as Sugar Limestone.
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The courses of the warm Agulhas current (red) along the east coast of South Africa, and the cold Benguela current (blue) along the west coast. Note that the Benguela current does not originate from Antarctic waters in the South Atlantic Ocean, but from upwelling of water from the cold depths of the Atlantic Ocean against the west coast of the continent. The two currents do not "meet" anywhere along the south coast of Africa. The chlorophyll concentration (or plankton density) in the oceans surrounding Southern Africa.
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Note the very high plankton density (the red colour) in the cold waters off the western coast. The temperature of the water and its fertility is due to its upwelling, along the coast. The vast majority of South Africa's border consists of the ocean—or two oceans, which, according to the International Hydrographic Organization, officially meet at Cape Agulhas, the most southern point of Africa. Its territory includes Marion and Prince Edward Islands, nearly south of Cape Town in the sub-antarctic Indian Ocean.
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In the winter, the northeasterly trade winds do not provide any moisture except in mountainous areas of northern Somalia, where rainfall in late autumn can produce annual totals as high as 500 mm (20 in). On the eastern coast, a strong upwelling and the fact that the winds blow parallel to the coast means annual rainfall can be as low as 50 mm (2 in). The climate in Ethiopia varies considerably between regions. It is generally hotter in the lowlands and temperate on the plateau.
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The total fluxes of brackish water through the river mouth during tidal events is often much higher (often by a factor of 10 to 100) than the volume flux from riverine inflow. Therefore, if measurements are not precise, the estimate of the net flux will be unreliable. Direct measurements of the return coefficient are often complicated by unsteady oceanic events such an upwelling, the passage of an eddy, or storms, so the success of a correct direct measurement of the return coefficient is rare.
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Acartia tonsa is a calanoid copepod species that can be found in a large portion of the world's estuaries and areas of upwelling where food concentrations are high. Like many plankton common to estuarine ecosystems, they can live in a wide range of temperatures and salinities. The wide distribution of Acartia tonsa may be a result of these copepods being transported as ballast in ships. Their tolerance to changes in salinity has likely contributed to their success as an invasive species in some regions.
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These zones are identified by typical seismic velocities between 7.2-7.7 km/s and are usually interpreted as layers of mafic to ultramafic rocks that have underplated the transitional crust. Asthenospheric upwelling leads to the formation of a mid-ocean ridge and new oceanic crust progressively separates the once-conjoined rift halves. Continued volcanic eruptions spread lava flows across transitional crust and onto oceanic crust. Due to the high rate of magmatic activity the new oceanic crust forms much thicker than typical oceanic crust.
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Examples of fauna observed at Coral Patch Seamount Many seamounts are biodiversity hotspots, as they interact with ocean currents enhancing the biological productivity around them. In the case of the northeast Atlantic seamounts, deep ocean currents are diverted at the seamount inducing upwelling. Outcropping rocks permit the settlement of species that would not find suitable substrates on sediment covered seafloor. Underwater video has identified a number of animals living on Coral Patch Seamount, but in general animals are rare and corals do not form large colonies.
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Most of the heat flow from the thicker continental crust is attributed to internal radiogenic sources; in contrast the thinner oceanic crust has only 2% internal radiogenic heat. The remaining heat flow at the surface would be due to basal heating of the crust from mantle convection. Heat fluxes are negatively correlated with rock age, with the highest heat fluxes from the youngest rock at mid-ocean ridge spreading centers (zones of mantle upwelling), as observed in the global map of Earth heat flow.
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The Tyrrhenian and Ionian meet in Straits of Messina, generating powerful currents and strong turbulence, aggravated by the abrupt changes of sea bottom topography in the vicinity of the town of Messina. As a consequence, many species known as rare in the Mediterranean are found in large numbers in the straits. It is common to find deep species at the surface and vice versa, or open-sea species along the coast. The upwelling water drags abyssal species to the surface and sometimes strands them on the shore.
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Purple sulfur bacteria are able to affect their environment by contributing to nutrient cycling, and by using their metabolism to alter their surroundings. They are able to play a significant role in primary production suggesting that these organisms affect the carbon cycle through carbon fixation. Purple sulfur bacteria also contribute to the phosphorus cycle in their habitat, and the iron cycle. Through upwelling of these organisms, phosphorus, a limiting nutrient in the oxic layer of lakes, is recycled and provided to heterotrophic bacteria for use.
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Almost all research into solar radiation management has to date consisted of computer modelling or laboratory tests. A 2014 paper in Nature found that among a variety of climate engineering subcategories including three carbon dioxide removal techniques (afforestation, ocean iron fertilization, and ocean alkalinization), as well as ocean upwelling, only solar radiation management was able to return global average temperatures to pre-industrial levels. Climate engineering approaches are sometimes viewed as potential options for limiting climate change or its impacts, alongside mitigation and adaptation. Ebook: .
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It is found on just two islands; Fernandina, and the northern and western coasts of Isabela. Distribution associates with the seasonal upwelling of the eastward flowing Equatorial Undercurrent (or Cromwell Current) which provides cold nutrient rich water to these western islands of the archipelago. The population has undergone severe fluctuations; the 1983 an El Niño-Southern Oscillation (ENSO) event resulted in a 50% reduction of the population to just 400 individuals. The population recovered quickly, however, and was estimated to number 900 individuals by 1999.
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The formation and development of plumes in the early mantle contributed to triggering the lateral movement of crust across the Earth's surface. The effect of upwelling mantle plumes on the lithosphere can be seen today through local depressions around hotspots such as Hawaii. The scale of this impact is much less than that exhibited in the Archean eon where mantle temperatures were much greater. Localised areas of hot mantle rose to the surface through a central plume wedge, weakening the damaged and already thin lithosphere.
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The nutrient contribution to False Bay surface waters by upwelling appears to be greater than that of terrestrial sources by runoff and groundwater seepage, but pollutants from terrestrial sources can be persistent and can have adverse effects on coastal ecosystems and recreational activities. Mixing with offshore water has a significant effect on surf zone and inshore water quality, but the effects of microbial processes on inshore water quality and the relative contribution of anthropogenic sources of nutrients remains unknown, but likely to be increasing.
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Assessment of the Conservation Values of the Bonney Upwelling Area: A Component of the Commonwealth Marine Conservation Assessment Program 2002–2004: Report to Environment Australia. Published by CSIRO Marine Research (now CSIRO Marine and Atmospheric Research) and Environment Australia, Dec. 2002. Accessed 12 July 2013. The industry is a significant employer and directly generates approximately $30 million in export and domestic earnings for the town with major flow-on benefits through local seafood processing (both export and domestic), transport & engineering services, fuel supplies and other ancillary industries.
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Mount McKay, a mafic sill related to volcanism of the Midcontinent Rift System in Thunder Bay, Ontario. During the Mesoproterozoic era of the Precambrian period 1,109 million years ago, northwestern Ontario began to split apart to form the Midcontinent Rift System, also called the Keweenawan Rift. Lava flows created by the rift in the Lake Superior area were formed from basaltic magma. The upwelling of this magma was the result of a hotspot which produced a triple junction in the vicinity of Lake Superior.
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Plate motion based on Global Positioning System (GPS) satellite data from NASA JPL. Each red dot is a measuring point and vectors show direction and magnitude of motion. It has generally been accepted that tectonic plates are able to move because of the relative density of oceanic lithosphere and the relative weakness of the asthenosphere. Dissipation of heat from the mantle is acknowledged to be the original source of the energy required to drive plate tectonics through convection or large scale upwelling and doming.
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During the austral summer, high-pressure systems over the Great Australian Bight cause southeasterly winds to blow over the coasts of Victoria and South Australia. When winds blow parallel to the shoreline, Ekman transport pushes water to the left of the wind direction (in the southern hemisphere), which in this case is westward and offshore. To replace the water moving offshore, cold waters from the ocean floor rise to the surface. During upwelling events, local sea surface temperature drops by 2-3 degrees Celsius.
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The materials for the building were shipped to Big River about to the north, then carted along the beach and hauled up a light tramway. The keeper's house is now a Department of Conservation hut. The Kahurangi upwelling system makes the area rich in oceanic biodiversity and the waters off Kahurangi Point is one of areas being frequented by pygmy blue whales along with off South Taranaki Bight which was discovered in 2007 and was confirmed in 2014.Torres G. L.. Klinck H.. et al. 2016.
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Upwelling of cooler waters further decayed the deep convection, prompting the NHC to downgrade Marty to a tropical storm at 06:00 UTC (1 a.m. CDT) on September 29. Continuing to steadily weaken, Marty degenerated into a post-tropical low a day later about 140 mi (225 km) west-southwest of Acapulco, while still producing gale-force winds. The shallow system turned westwards in the low- level flow and eventually opened up into a trough twelve hours later about 195 mi (315 km) west of Acapulco.
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Other proposed abiogenic processes include radiolysis by the radioactive isotope of potassium, 40K, or annual turnover of basin water combined with upwelling of iron-rich water in a stratified ocean. Another abiogenic mechanism is photooxidation of iron by sunlight. Laboratory experiments suggest that this could produce a sufficiently high deposition rate under likely conditions of pH and sunlight. However, if the iron came from a shallow hydrothermal source, other laboratory experiments suggest that precipitation of ferrous iron as carbonates or silicates could seriously compete with photooxidation.
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Rifting is said to have begun in the Late Cretaceous epoch to Paleogene period. At that time the African plate was experiencing far-field stresses caused by portions of the northern boundary of the African plate subducting under the Eurasian plate. Today, the Arabian plate is experiencing a crustal down pull, or slab pull, that has separated from the African plate. At the same time of the subduction in the north there was mantle upwelling causing the crust to down warp and swell into domes.
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While upwelling promotes abundant primary and secondary production in the upper parts of the water column and near the coast, deeper waters with limited oxygen exchange create hypoxic areas called oxygen minimum zones at the coastal shelf and upper coastal slope. The Benguela oxygen minimum zone starts around a depth of 100 m and is a few hundred meters thick. Bacteria that use sulpher rather than oxygen reside in the oxygen minimum zone. The most abundant fishes in the Benguela system are Sardinops and Engraulis.
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Upwelling of deep water under the sea ice brings substantial amounts of nutrients. As the ice melts, the melt water provides stability and the critical depth is well below the mixing depth, which allows for a positive net primary production. As the sea ice recedes epontic algae dominate the first phase of the bloom, and a strong bloom dominate by diatoms follows the ice melt south. Another phytoplankton bloom occurs more to the north near the Antarctic convergence, here nutrients are present from thermohaline circulation.
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The solar cycle spans approximately 11 years, from solar minimum to the following minimum. Since the solar magnetic field is continually wound up due to the faster rotation of mass at the Sun's equator (differential rotation), sunspot activity will be more pronounced at solar maximum where the magnetic field is more twisted. Associated with sunspots are coronal loops, loops of magnetic flux, upwelling from the solar interior. The magnetic flux pushes the hotter photosphere aside, exposing the cooler plasma below, thus creating the relatively dark sun spots.
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The south-eastern maximum is due to the direction of the predominant winds. The maximum in the west is mainly due to the effects of the sun when the sky is clear, due to anabatic upwelling of air in the valleys bringing cloud up the mountain by the early afternoon. Without this effect this area would be expected to be in a rain shadow. Above most of the precipitation falls as snow, but as the air is very dry there is not much of this.
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Organisms like crabs, nematodes, small fish, corals, and other species cycle to these areas as the tides rise and fall typically about every twelve hours. The cycle movements are associated with foraging of marine and bird species. Typically, during low tide smaller or younger species will emerge to forage because they can survive in the shallower water and have less chance of being preyed upon. During high tide, larger species can be found due to the deeper water and nutrient upwelling from the tidal movements.
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Close to 90% of the world's fishery catches come from oceans and seas, as opposed to inland waters. These marine catches have remained relatively stable since the mid-nineties (between 80 and 86 million tonnes). Most marine fisheries are based near the coast. This is not only because harvesting from relatively shallow waters is easier than in the open ocean, but also because fish are much more abundant near the coastal shelf, due to the abundance of nutrients available there from coastal upwelling and land runoff.
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20 mm/yr and in the SWIR there is an absence of volcanic activity along stretches of ridge axis. Along large sections, the SWIR runs obliquely relative to the spreading direction, typically about 60°. Because obliquity increases ridge length while decreasing mantle upwelling rates, the SWIR is transitional between slow and ultra-slow ridges. The slow- spreading sections of the SWIR have magmatic segments linked by transform faults, while the ultra-slow sections lack such transforms and have magmatic segments linked by amagmatic troughs.
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The reduction in upwelling leads to fish kills off the shore of Peru. The local fishing industry along the affected coastline can suffer during long-lasting El Niño events. The world's largest fishery collapsed due to overfishing during the 1972 El Niño Peruvian anchoveta reduction. During the 1982–83 event, jack mackerel and anchoveta populations were reduced, scallops increased in warmer water, but hake followed cooler water down the continental slope, while shrimp and sardines moved southward, so some catches decreased while others increased.
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The volcano has been dormant since the 7200 BP eruption. On October 10, 2007, a small swarm of earthquakes appeared 20 kilometres west of Nazko Cone.Chronology of Events in 2007 at Nazko Cone Most of these earthquakes were magnitude 1.0 or less; some as strong as M 3.1 or 3.2 were centered 25 kilometres below the surface. The cause of this seismic activity is believed to be the upwelling of magma because the area is not close to any faults or tectonic plate boundaries.
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The Peruvian Desert has a low range of temperature changes due to the moderating effect of the nearby Pacific Ocean. Because of the upwelling of cold coastal waters and subtropical atmospheric subsidence, the desert is one of the most arid on Earth. Summer (December through March) is warm and sunny with temperatures above during the day, and temperatures that average over . In the winter (June through September) the weather is cool and cloudy with temperatures that vary from at night to during the day.
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The Bering Sea shelf break is the dominant driver of primary productivity in the Bering Sea. This zone, where the shallower continental shelf drops off into the North Aleutians Basin is also known as the "Greenbelt". Nutrient upwelling from the cold waters of the Aleutian basin flowing up the slope and mixing with shallower waters of the shelf provide for constant production of phytoplankton. The second driver of productivity in the Bering Sea is seasonal sea ice that, in part, triggers the spring phytoplankton bloom.
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De Filippi's petrel spends the greatest part of the year at sea in the eastern Pacific Ocean south of the equator where the Humboldt Current causes a major upwelling of nutrient-rich cold water. Here the bird feeds by skimming across the surface of the water and scooping up prey on the wing. It nests in two island groups off the coast of Chile. On the Desventuradas Islands, the largest colony is on San Ambrosio where more than 10,000 birds were estimated to be present in 1970.
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Coastal upwelling regions usually have high nitrate and chlorophyll levels as a result of the increased production. However, there are regions of high surface nitrate but low chlorophyll that are referred to as HNLC (high nitrogen, low chlorophyll) regions. The best explanation for HNLC regions relates to iron scarcity in the ocean, which may play an important part in ocean dynamics and nutrient cycles. The input of iron varies by region and is delivered to the ocean by dust (from dust storms) and leached out of rocks.
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Below convergence zones narrow jets of downward flow form and the magnitude of the current will be comparable to the horizontal flow. The downward propagation will typically be in the order of meters or tenths of meters and will not penetrate the pycnocline. The upwelling is less intense and takes place over a wider band under the divergence zone. In wind speeds ranging from the maximum vertical velocity ranged from with a ratio of down-welling to wind velocities ranging from −0.0025 to −0.0085.
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The California Current System comprises the eastern boundary of the North Pacific Subtropical Gyre and flows south along the coast of California. Here coastal upwelling drives the eastern boundary current and an undercurrent that flows poleward. In the western region of the North Pacific, the surface of the Subtropical Gyre generally has a "C-shape". The Kuroshio current and Kuroshio Extension roughly from the outside of this "C-shape" where it then turns westwards into recirculation, where it then flows south parallel to the Kuroshio Current.
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Elsevier, New York, pp 49–52. The growth of marine phytoplankton is generally limited by the availability of nitrates and phosphates, which can be abundant in agricultural run-off as well as coastal upwelling zones. Coastal water pollution produced by humans and systematic increase in seawater temperature have also been implicated as contributing factors in red tides. Other factors such as iron-rich dust influx from large desert areas such as the Sahara Desert are thought to play a major role in causing red tides.
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Tessellated pavement, a rare rock formation on the Tasman Peninsula The island was adjoined to the mainland of Australia until the end of the last glacial period about 11,700 years ago. Much of the island is composed of Jurassic dolerite intrusions (the upwelling of magma) through other rock types, sometimes forming large columnar joints. Tasmania has the world's largest areas of dolerite, with many distinctive mountains and cliffs formed from this rock type. The central plateau and the southeast portions of the island are mostly dolerites.
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The peak ground acceleration (PGA) was extremely high, and simultaneous vertical and horizontal ground movement was "almost impossible" for buildings to survive intact. Liquefaction was significantly greater than that of the 2010 quake, causing the upwelling of more than 200,000 tonnes of silt which needed to be cleared. The increased liquefaction caused significant ground movement, undermining many foundations and destroying infrastructure, damage which "may be the greatest ever recorded anywhere in a modern city". 80% of the water and sewerage system was severely damaged.
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Rocky and sandy shores of Dakhla. Like most areas in Western Sahara, Dakhla and vicinity areas are very poor in vegetation and are mostly covered by the Sahara Desert. Unlike on land however, sea waters are or had been very rich in sea life due to the highly productive Current System of Canary flowing offshore and the renown Nouadhibou upwelling which is located nearby as well. These environmental factors provide excellent conditions for local fisheries, and result in strong local biodiversity for birds in particular.
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Coastal margins have high sedimentation rates due to sediment input by rivers, which account for the vast majority of sediment delivery to the ocean. In most cases, sediments are deposited near the river mouth or are transported in the alongshore direction due to wave forcing. In some places sediment falls into submarine canyons and is transported off-shelf, if the canyon is sufficiently large or the shelf is narrow. Coastal margins also contain diverse and plentiful marine species, especially in places that experience periodic upwelling.
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This gives them a crystalline structure that resembles ice and can appear as white to yellow mounds covered by sediment on the seafloor. The region is influenced by a major ocean current system. Off the coast, the west wind drift current splits to create the Alaska and the California currents (the California current system). The direction and strength of the currents regulate the upwelling/downwelling regime along the coast, with a flow towards the equator in summer (California current) and reversal in winter (Alaska current).
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From an oceanographic point of view, the equatorial cold tongue is caused by easterly winds. Were the earth climate symmetric about the equator, cross-equatorial wind would vanish, and the cold tongue would be much weaker and have a very different zonal structure than is observed today.Ocean-atmosphere interaction in the making of the Walker circulation and equatorial cold tongue The Walker cell is indirectly related to upwelling off the coasts of Peru and Ecuador. This brings nutrient-rich cold water to the surface, increasing fishing stocks.
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Environmental conditions remained highly favorable for intensification and the NHC forecast the system to strengthen just below Category 5 status by September 13; however, the system soon weakened and degraded to Category 3 status by 18:00 UTC. Florence steadily grew in size during this time, with tropical storm-force winds extending 195 mi (315 km) by the end of September 12. The hurricane's core soon unraveled on September 13 as mid-level wind shear increased and upwelling of colder water reduced available energy.
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Production of REE around the world A rare-earth element-iron-lead-zinc (REE-Fe-Pb-Zn) system was formed from extensional rifting with upwelling of mantle, and therefore magma fractionation. There were multiple rifting events resulting in the deposition of iron minerals and the occurrence rare earth element was closely related to the iron and carbonatite dykes. The REE-Fe-Pb-Zn system occurs in an alternating volcanic and sedimentary succession. Apart from REE, LREE (light rare earth elements) are also found in carbonatite dykes.
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Venus flytrap sea anemone is a passive suspension feeder, and orients itself on its often slender column so that it faces the upwelling current. Its pedal disc is small, and its tentacles are short compared to the large, concave oral disc, which is funnel or mushroom- shaped. It extends its tentacles in two rows, one reflexed back and one sloping forward, and collects food particles as they drift past. Although usually considered sessile, the Venus flytrap sea anemone sometimes moves, particularly as a juvenile.
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From 1979 to 2005 the microwave sounding units (MSUs) and since 1998 the Advanced Microwave Sounding Units on NOAA polar orbiting satellites have measured the intensity of upwelling microwave radiation from atmospheric oxygen. The intensity is proportional to the temperature of broad vertical layers of the atmosphere, as demonstrated by theory and direct comparisons with atmospheric temperatures from radiosonde (balloon) profiles. Different frequencies sample a different weighted range of the atmosphere, depending on the absorption depth (i.e., optical depth) of the microwaves through the atmosphere.
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As the weak typhoon continued west, upwelling of itself due to its quasi-stationary movement combined with moderate wind shear hindered significant intensification of Kammuri over the next three days. It eventually entered the Philippine Area of Responsibility (PAR) with PAGASA assigning the name Tisoy on November 30. After entering the PAGASA's area of responsibility, Kammuri began to show signs of intensification again, and PAGASA noted the possibility of Kammuri making landfall in the Philippines as a somewhat powerful typhoon. After very slowly moving west and on approach to the Philippines, the system began to accelerate towards the Philippines and then began to rapidly intensify by the time it came within 200 miles of the coast of Catanduanes, due to the lowering of wind shear and increasing ocean heat content; all of which combined to counteract the upwelling. It became a category 2 typhoon and soon after, a category 3 typhoon. Kammuri reached its peak intensity as a 140mph category 4-equivalent typhoon on 07:00 UTC on December 2, and PAGASA reported that Kammuri had made its first landfall over Gubat, Sorsogon at 11:00 pm, 2 December, very shortly after reaching its peak intensity.
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These flood basalt lava flows were erupted during a single event that lasted less than five million years. Analysis of the chemical composition of the lavas gives important clues about the origin and dynamics of the flood basalt volcanism. The lowermost lavas were produced by melting in the garnet stability field below the surface at a depth of more than in a mantle plume environment beneath the North American lithosphere. As the mantle plume intruded rocks of the Canadian Shield, it created an upwelling zone of molten rock known as the Mackenzie hotspot.
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Some bacteria interact with diatoms, and form a critical link in the cycling of silicon in the ocean. One anaerobic species, Thiomargarita namibiensis, plays an important part in the breakdown of hydrogen sulfide eruptions from diatomaceous sediments off the Namibian coast, and generated by high rates of phytoplankton growth in the Benguela Current upwelling zone, eventually falling to the seafloor. Bacteria-like Archaea surprised marine microbiologists by their survival and thriving in extreme environments, such as the hydrothermal vents on the ocean floor. Alkalotolerant marine bacteria such as Pseudomonas and Vibrio spp.
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The mantle of a planet with plate tectonics has driving forces that exceed the yield strength of the brittle lithosphere, causing the lithosphere to fracture into plates that move relative to each other. A critical element of the plate tectonic system is these lithospheric plates become negatively buoyant at some point in their evolution, sinking into the mantle. The surface mass deficit is balanced by new plate being formed elsewhere through upwelling mantle plumes. Plate tectonics is an efficient method of heat transfer from the interior of the planet to the surface.
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Tropical Storm Bud approaching the Baja California Peninsula on June 14 Despite exhibiting trochoidal oscillations as is typical for major hurricanes, Bud continued to move generally north-northwestward after peak. Progressively cooler water and ocean heat content values near zero resulted in significant ocean upwelling underneath the cyclone, leading to a rapid reduction in central convection. Bud then began to weaken, falling to Category 1 intensity by 06:00 UTC on June 13 as its eye disappeared. Bud continued to weaken, falling to tropical storm status 6 hours later.
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After briefly weakening to a tropical depression off the coast of Haiti, Jeanne turned sharply northward and regained tropical storm status. Weak steering currents in the vicinity of the storm caused it to take a long, clockwise loop roughly 575 mi (925 km) east of the Bahamas. During this loop, Jeanne re-attained hurricane status although it fluctuated in intensity due to the upwelling of cooler waters. By September 24, the storm maintained a steady westward track and reached Category 3 strength on the Saffir–Simpson Hurricane Scale.
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Moreover, winters will usually be wetter than normal in the south and southwest with more snowfall in the alpine areas, but drier in the east coast due to less moist onshore flows from the east. This phase will usually be more frequent with an El Niño event. Winds associated with the Southern Annular Mode cause oceanic upwelling of warm circumpolar deep water along the Antarctic continental shelf, which has been linked to ice shelf basal melt, representing a possible wind-driven mechanism that could destabilize large portions of the Antarctic ice sheet.
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During this time, Gamede executed a small loop, and the cyclone attained its peak intensity. The MFR estimated peak 10 minute winds of 165 km/h (105 mph) late on February 25\. At the same time, the JTWC estimated peak 1 minute winds of 195 km/h (120 mph). While remaining nearly stationary northwest of the Mascarene Islands, Gamede lost some of its deep convection due to upwelling, the process in which a stationary storm causes the water temperatures to decrease by bringing the cooler, deeper waters to the surface.
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At the present time the CCD in the Pacific Ocean is about 4200–4500 metres except beneath the equatorial upwelling zone, where the CCD is about 5000 m. In the temperate and tropical Atlantic Ocean the CCD is at approximately 5000 m. In the Indian Ocean it is intermediate between the Atlantic and the Pacific at approximately 4300 meters. The variation in the depth of the CCD largely results from the length of time since the bottom water has been exposed to the surface; this is called the "age" of the water mass.
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Isotopic samples taken from the Pacific-Antarctic ridge basalts have disassembled the long-held belief that there was a coherent geochemical province stretching from the Australian- Antarctic discordance to the Juan de Fuca plate. Instead, samples have shown that there are instead two distinct geochemical domains above and below the Easter microplate. Measurements of the average depth of ridge axes also shows that this boundary line lies on the southeastern side of the Darwin Rise/Pacific Superswell. It was concluded that this upwelling was responsible for the disparity between the two geochemical regions.
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Among the Uranian satellites, Ariel appears to have the youngest surface with the fewest impact craters and Umbriel's the oldest. Miranda has fault canyons deep, terraced layers, and a chaotic variation in surface ages and features. Miranda's past geologic activity is thought to have been driven by tidal heating at a time when its orbit was more eccentric than currently, probably as a result of a former 3:1 orbital resonance with Umbriel. Extensional processes associated with upwelling diapirs are the likely origin of Miranda's 'racetrack'-like coronae.
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El Niño and La Niña are opposite surface temperature anomalies of the Southern Pacific, which heavily influence the weather on a large scale. In the case of El Niño, warm surface water approaches the coasts of South America which results in blocking the upwelling of nutrient-rich deep water. This has serious impacts on the fish populations. In the La Niña case, the convective cell over the western Pacific strengthens inordinately, resulting in colder than normal winters in North America and a more robust cyclone season in South-East Asia and Eastern Australia.
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The cold Benguela current is a mineral-rich upwelling current, which flows away to the north along the western coastline, after having come up from the cold depths of the Atlantic Ocean. Plankton grow in these fertile waters, and support large numbers of fish, and therefore a prosperous (in the past) fishing industry. Over-fishing has, however, reduced the importance of this fishing industry both for the local as well as the country's economy. The east coast has the north-to-south Mozambique/Agulhas Current, which provides warm waters.
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The abundance of methane, ethane and acetylene at Neptune's equator is 10–100 times greater than at the poles. This is interpreted as evidence for upwelling at the equator and subsidence near the poles because photochemistry cannot account for the distribution without meridional circulation. In 2007, it was discovered that the upper troposphere of Neptune's south pole was about 10 K warmer than the rest of its atmosphere, which averages approximately . The temperature differential is enough to let methane, which elsewhere is frozen in the troposphere, escape into the stratosphere near the pole.
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Iceland lies on the spreading axis of the Mid-Atlantic Ridge (MAR) where it is influenced by the Iceland hotspot, a major mantle upwelling. The active spreading axis of the MAR is moving westward with respect to the hotspot. This means that the active rifts above the hotspot have progressively jumped towards the east, causing the development of two major transform zones in the north and south of the island. To the south the zone is the South Iceland Seismic Zone (SISZ), which has a west–east trend and is about 20 km wide.
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In September 2007, Lovelock and Chris Rapley proposed the construction of ocean pumps to pump water up from below the thermocline to "fertilize algae in the surface waters and encourage them to bloom". The basic idea was to accelerate the transfer of carbon dioxide from the atmosphere to the ocean by increasing primary production and enhancing the export of organic carbon (as marine snow) to the deep ocean. A scheme similar to that proposed by Lovelock and Rapley is already being independently developed by a commercial company.Biological Ocean Sequestration of Using Atmocean Upwelling , Atmocean.
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Impurities in the water ice crust of Europa are presumed both to emerge from the interior as cryovolcanic events that resurface the body, and to accumulate from space as interplanetary dust. Tholins bring important astrobiological implications, as they may play a role in prebiotic chemistry and abiogenesis. The presence of sodium chloride in the internal ocean has been suggested by a 450 nm absorption feature, characteristic of irradiated NaCl crystals, that has been spotted in HST observations of the chaos regions, presumed to be areas of recent subsurface upwelling.
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The active rift model sees rupture driven by hotspot or mantle plume activity. Upwellings of hot mantle, known as mantle plumes, originate deep in Earth and rise to heat and thin the lithosphere. Heated lithosphere thins, weakens, rises, and finally rifts, Enhanced melting following continental breakup is very important in VPMs, creating thicker than normal oceanic crust of 20 to 40 km thick. Other melts caused by convection related upwelling form reservoirs of magma from which dike swarms and sills eventually radiate to the surface, creating the characteristic seaward dipping lava flows.
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Langmuir circulation results in the occurrence of thin, visible stripes, called windrows on the surface of the ocean parallel to the direction that the wind is blowing. If the wind is blowing with more than 3 m s−1, it can create parallel windrows alternating upwelling and downwelling about 5–300 m apart. These windrows are created by adjacent ovular water cells (extending to about deep) alternating rotating clockwise and counterclockwise. In the convergence zones debris, foam and seaweed accumulates, while at the divergence zones plankton are caught and carried to the surface.
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Arcata has a cool summer Mediterranean climate (Köppen Csb), which is dominated by marine influences associated with Humboldt Bay and the Pacific Ocean. These influences make the climate in the city much cooler than that of a typical Mediterranean climate and more on par with that of an oceanic climate. On average, Arcata experiences of rain per year, though there is a short but pronounced dry season from June to September. Northerly winds keep the spring very cool and create a coastal upwelling of deep, cold ocean water.
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Marine deposition was common across much of the area in the Paleozoic. Within the Mackenzie Basin, tabulate and rugose corals grew formed the Horn Plateau Formation—a group of isolated reefs from the Devonian fed by nutrients from eroding Canadian Shield rocks and offshore upwelling in the ocean. The Selwyn Basin, which now spans into the Yukon Territory formed at the same time and accumulated graptolite fossils and bitumen. The siliclastic, fossiliferous wackestone and mudstone of the Ordovician Bad Cache Rapids Formation record a shallow shelf environment on Southampton Island.
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Northward surface flow transports a substantial amount of heat energy from the tropics and Southern Hemisphere toward the North Atlantic, where the heat is lost to the atmosphere due to the strong temperature gradient. Upon losing its heat, the water becomes denser and sinks. This densification links the warm, surface limb with the cold, deep return limb at regions of convection in the Nordic and Labrador Seas. The limbs are also linked in regions of upwelling, where a divergence of surface waters causes Ekman suction and an upward flux of deep water.
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The steep slopes of the canyons and seamounts interact with oceanographic currents to create localized eddies, causing upwelling. The currents lift nutrients to surface waters, fueling an outburst of phytoplankton and zooplankton that form the base of the food chain. These plankton draw large schools of small fish, and those fish draw even larger predators such as whales, sharks, tunas and seabirds to the area. In all, “the geology, currents, and productivity create diverse and vibrant ecosystems.” As a result, the area has been the subject of “intense scientific interest” and discovery since the 1970s.
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The storm weakened due to land interaction and upwelling, falling below major hurricane late on September 3\. An eastward-moving, large mid-level trough forced Dorian to move north- northwestward and then northward, causing it to remain offshore Florida. The cyclone re-strengthened into a Category 3 hurricane over the Gulf Stream on September 5, but weakened back to a Category 2 later that day. Dorian then curved northeastward and scraped the Outer Banks of North Carolina on September 6 before moving ashore at Cape Hatteras with winds of 100 mph (155 km/h).
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Hotspots are sites of upwelling of relatively hot mantle, possibly associated with mantle plumes, that cause partial melting of the asthenosphere. This type of magmatism forms volcanic seamounts or oceanic islands when they become emergent. Over short geological timescales the hotspots appear to be fixed relative to one another, forming a reference frame against which plate motions can be measured. As tectonic plates move relative to a hotspot, the location of magmatic activity on the plate shifts, causing the development of time-progressive chains of volcanoes such as the Hawaiian–Emperor seamount chain.
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However, the return of dry air and upwelling caused the storm to deteriorate into a tropical storm. Paralleling the Mexican coast, Carlos regained hurricane intensity on June 15 and peaked with sustained winds of 90 mph (150 km/h) and a pressure of 978 mbar (hPa; 28.88 inHg) the next day. Wind shear and dry air afterwards caused Carlos to rapidly weaken, falling to tropical storm intensity on June 17 and degenerating into a remnant low- pressure area hours later. Carlos' formation prompted coastal authorities to enact precautionary measures along states deemed at risk.
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The north Atlantic is characterized by strong, large-scale anomalies of the gravity field and the geoid. The geoid rises up to 70 m above the geodetic reference ellipsoid in an approximately circular area with a diameter of several hundred kilometers. In the context of the plume hypothesis, this has been explained by the dynamic effect of the upwelling plume which bulges up the surface of the Earth. Furthermore, the plume and the thickened crust cause a positive gravity anomaly of about 60 mGal (=0.0006 m/s²) (free-air).
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This upwelling magma then cools and solidifies by conduction and convection of heat to form new oceanic crust. Accretion occurs as mantle is added to the growing edges of a tectonic plate, usually associated with seafloor spreading. The age of oceanic crust is therefore a function of distance from the mid-ocean ridge. The youngest oceanic crust is at the mid-ocean ridges, and it becomes progressively older, cooler and denser as it migrates outwards from the mid- ocean ridges as part of the process called mantle convection.
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It takes the rain with it, causing extensive drought in the western Pacific and rainfall in the normally dry eastern Pacific. El Niño's warm rush of nutrient- poor tropical water, heated by its eastward passage in the Equatorial Current, replaces the cold, nutrient-rich surface water of the Humboldt Current. When El Niño conditions last for many months, extensive ocean warming and the reduction in Easterly Trade winds limits upwelling of cold nutrient-rich deep water and its economic impact to local fishing for an international market can be serious.
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Thin layers persist from hours to weeks while other small-scale patches of plankton exist for minutes. The presence of nutrients as well as coastal fronts, eddies, and upwelling zones greatly increase the persistence of thin layers. One of the main criteria for an aggregation of plankton to be considered a thin layer is that the increased concentration at a certain depth of the water column must appear in subsequently measured profiles. However, thin layers are dynamic and horizontally extensive so their persistence cannot be defined using multiple measurements at only one location.
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Geological setting and some geochemistry of petroleum source rocks in the Permian Phosphoria Formation. Rocky Mountain Association of Geologists. The upwelling of cold, nutrient-rich marine water at that time stimulated the growth of plankton and nekton, resulting in the accumulation of organic matter on the sea floor. That, coupled with low rates of clastic and carbonate sedimentation, led to the high phosphate and hydrocarbon content of the formation, as well as elevated levels of cadmium, chromium, copper, fluorine, molybdenum, nickel, rare earth elements, selenium, uranium, vanadium, and zinc.
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It is unclear what causes HABs; their occurrence in some locations appears to be entirely natural, while in others they appear to be a result of human activities. Furthermore, there are many different species of algae that can form HABs, each with different environmental requirements for optimal growth. The frequency and severity of HABs in some parts of the world have been linked to increased nutrient loading from human activities. In other areas, HABs are a predictable seasonal occurrence resulting from coastal upwelling, a natural result of the movement of certain ocean currents.
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The growth of marine phytoplankton (both non-toxic and toxic) is generally limited by the availability of nitrates and phosphates, which can be abundant in coastal upwelling zones as well as in agricultural run-off. The type of nitrates and phosphates available in the system are also a factor, since phytoplankton can grow at different rates depending on the relative abundance of these substances (e.g. ammonia, urea, nitrate ion). A variety of other nutrient sources can also play an important role in affecting algal bloom formation, including iron, silica or carbon.
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This breaking is much more pronounced in the winter hemisphere where this region is called the surf zone. This breaking is caused due to a highly non-linear interaction between the vertically propagating planetary waves and the isolated high potential vorticity region known as the polar vortex. The resultant breaking causes large scale mixing of air and other trace gases throughout the midlatitude surf zone. The timescale of this rapid mixing is much smaller than the much slower timescales of upwelling in the tropics and downwelling in the extratropics.
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Once the plume head breaks the surface, crust either side of the head is forced downwards through the conservation of mass, initiating subduction. Numerical modelling shows only strongly energetic plumes are capable of weakening the lithosphere enough to rupture it, such plumes would have been present in the hot Archean mantle. Pre-tectonic subduction can also be inferred from the internal volcanism on Venus. Artemis Corona is a large plume formed by the upwelling of mantle derived magma and is on a scale potentially comparable to that in the Archean mantle.
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The water circulation is primarily wind driven. Gordon's Bay is in the wind shadow of the Hottentots-Holland Mountains for south easterly winds, and this causes a semi-permanent anticyclonic eddy and associated anticlockwise gyre, in the opposite direction to the usual cyclonic circulation of the main part of the bay. In the summer to early autumn (January–March), cold water upwelling near Cape Hangklip causes a strong surface temperature gradient between the south- western and north-eastern corners of the bay. In winter the surface temperature tends to be much the same everywhere.
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The origin of the Samoan volcanic chain has been explained with either a hotspot influenced by the Tonga Trench or by cracking of the Pacific crust; today the preferred theory is that the Samoan chain is a hotspot-generated volcanic chain while the "anomalous" younger volcanism is produced through an interaction between the islands and the Tonga Trench and a neighboring transform fault. This hotspot is under the influence of the mantle flows triggered by the Tonga Trench, which distort the rising plume and also changes its upwelling flux. This interaction has only begun recently.
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Analysis of statoliths suggest that the life span of this species is roughly one year but growth rates are subject to considerable individual variation and are correlated variable environmental effects of the northern Benguela Upwelling System. Angolan flying squid are opportunistic predators and their prey includes a variety of fish species such as the Cape hake Merluccius capensis, in the northern Benguela Current. It is also an important prey item for a number of predatory fish species sharks and marine mammals and may make up the majority of their diet.
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These flood basalt lava flows were erupted during a single event that lasted less than five million years. Analysis of the chemical composition of the lavas gives important clues about the origin and dynamics of the flood basalt volcanism. The lowermost lavas were produced by melting in the garnet stability field below the surface at a depth of more than in a mantle plume environment beneath the North American lithosphere. As the mantle plume intruded rocks of the Canadian Shield, it created an upwelling zone of molten rock known as the Mackenzie hotspot.
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While almost all phytoplankton species are obligate photoautotrophs, there are some that are mixotrophic and other, non-pigmented species that are actually heterotrophic (the latter are often viewed as zooplankton). Of these, the best known are dinoflagellate genera such as Noctiluca and Dinophysis, that obtain organic carbon by ingesting other organisms or detrital material. Phytoplankton are crucially dependent on minerals. These are primarily macronutrients such as nitrate, phosphate or silicic acid, whose availability is governed by the balance between the so-called biological pump and upwelling of deep, nutrient-rich waters.
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The main rift or "syn-rift" stage describes the phase of active stretching and fault block rotation. Syn-rift subsidence results from the elastic/isostatic adjustment of the crust due to mechanical stretching of the lithosphere. The subsidence is counteracted by upwelling of the asthenosphere into the space created by the mechanical stretching and thermal upward displacement of the asthenosphere-lithosphere boundary, causing uplift of the rift zone. The fundamental architectural element in many extensional basins is the half-graben, formed within the hanging walls of major rift-bounding or intra-rift basin faults.
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El Niño is a reversal of the normal situation in the Pacific Ocean. Surface water is blown westwards by the prevailing winds and deeper water is forced upwards to replace it. Every now and then, the surface water sloshes back across the ocean, bringing warm water temperatures along the eastern coasts of the pacific. In non-El Niño years, the Cromwell current is forced to the surface by underwater seamounts near the Galapagos islands (this is called upwelling.) However, during El Nino years the current does not upwell in this way.
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The increased upwelling was caused by stronger winds, which in turn released more CO2 into the atmosphere enhancing global warming during the Holocene and the shrinkage of ice sheets. Thus, demonstrating that a possible cause of the warming was a change in ocean circulation. Holocene ocean temperature and climate evolution of the western Antarctic Peninsula. TEX86 proxy analysis of sediments from the western Antarctic Peninsula continental shelf documented the changing influence of warm Circumpolar Deep Water on regional glacier and sea ice extent since the last deglaciation, ~13,000 years ago.
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The GCFR is delimited to the north by the Cape Fold Belt and the limited space south of it resulted in the development of social networks out of which complex Stone Age technologies emerged. Human history thus begins on the coasts of South Africa where the Atlantic Benguela Upwelling and Indian Ocean Agulhas Current meet to produce an intertidal zone on which shellfish, fur seal, fish and sea birds provided the necessary protein sources. The African origin of this modern behaviour is evidenced by 70,000 years-old engravings from Blombos Cave, South Africa.
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The Point Reyes peninsula hosts 45% of North American bird species and almost 18% of California's plant species, including 23 threatened and endangered species. At the receiving end of one of California's major upwelling zones, this coastal habitat is also home to humpback and gray whales, seals, sea lions, and elephant seals. Point Reyes SMR and Point Reyes SMCA protect multiple habitats including exposed high energy rocky shoreline, sand & gravel beaches, offshore islets, surf grass, and soft & hard substrates, and the diverse fish, seabird and marine mammals associated with them.
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However, this is less likely as dolphins congregate in large pods with hundreds of members to prevent predation. The whale probably follows seasonal squid migrations from offshore in the summer to nearshore in the winter. It is possible it prefers a slope habitat as it allows the whale to herd squid against the wall, or it causes upwelling which the whale can ride on in order to save energy while hunting. Younger animals may congregate in shallower areas and adults in deeper areas; the slope around South Africa may be a nursery grounds.
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Colling, pp 42-44 This phenomenon was first noted by Fridtjof Nansen, who recorded that ice transport appeared to occur at an angle to the wind direction during his Arctic expedition during the 1890s.Pond & Pickard, p 101 Ekman transport has significant impacts on the biogeochemical properties of the world's oceans. This is because they lead to upwelling (Ekman suction) and downwelling (Ekman pumping) in order to obey mass conservation laws. Mass conservation, in reference to Ekman transfer, requires that any water displaced within an area must be replenished.
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On the other hand, if the wind is moving in such a way that surface waters move towards the shoreline then Ekman pumping will take place. The second mechanism of wind currents resulting in Ekman transfer is the trade winds both north and south of the equator pulling surface waters towards the poles. There is a great deal of Ekman suction at the equator because water is being pulled northward north of the equator and southward south of the equator. This leads to a divergence in the water, resulting in Ekman suction, and therefore, upwelling.
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The diorites found in the area are high in magnesium and REE (rare-earth elements), which suggest further that the rocks were formed from a mixture of the mantle and remelted basaltic crust. Overall, the presence of tonalite- trondhjemite-granodiorites, as well as the iron present for the banded iron formations (BIFs), are determined to have been caused by hydrothermal alteration at high temperatures. BIFs are typically found in intra-oceanic, arc or forearc settings, which are associated with convergent boundaries. The intrusions were formed when upwelling asthenosphere partially melted thick overlying oceanic crust.
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The outer margins of the wide continental shelves of Yucatán and Florida receive cooler, nutrient-enriched waters from the deep by a process known as upwelling, which stimulates plankton growth in the euphotic zone. This attracts fish, shrimp, and squid. River drainage and atmospheric fallout from industrial coastal cities also provide nutrients to the coastal zone. The Gulf Stream, a warm Atlantic Ocean current and one of the strongest ocean currents known, originates in the gulf, as a continuation of the Caribbean Current-Yucatán Current-Loop Current system.
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Large scale surface features due to dynamic topography are mid-ocean ridges and oceanic trenches. Other prominent examples include areas overlying mantle plumes such as the African superswell. The mid-ocean ridges are high due to dynamic topography because the upwelling hot material underneath them pushes them up above the surrounding seafloor. This provides an important driving force in plate tectonics called ridge push: the increased gravitational potential energy of the mid-ocean ridge due to its dynamic uplift causes it to extend and push the surrounding lithosphere away from the ridge axis.
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If the coronae formed through downwelling from a catastrophic disruption, then the concentric faults would present as compressed. If they formed through upwelling, such as by diapirism, then they would be extensional tilt blocks, and present extensional features, as current evidence suggests they do. The concentric rings would have formed as ice moved away from the heat source. The diapirs may have changed the density distribution within Miranda, which could have caused Miranda to reorient itself, similar to a process believed to have occurred at Saturn's geologically active moon Enceladus.
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In what is now Grand Portage State Park, upwelling magma did not reach the surface but intruded into fractures in the Rove Formation, cooling more slowly into diabase rather than basalt. One set of intrusions formed northeast-to-southwest trending sills while a later event formed northwest-to-southeast trending dikes. Together they are known as the Logan Intrusions after Canadian geologist William Edmond Logan. From 2 million years ago to 10,000 years ago a series of glacial periods repeatedly covered the region with ice, scouring the bedrock and scooping out a great basin.
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The primary source of iron into the estuary is from geologic rock weathering and subsequent runoff delivery to the system. In addition, some iron may come from the Pacific Ocean and is transported into the estuary during tidal oscillation, enhanced seasonally during periods of upwelling. Iron inputs derived from riverine and oceanic origins are typically on the magnitude of 14-30 nM and 6 nM in concentration respectively. These sources of iron are generally sufficient to meet biological demands, including those of primary production, in the estuary and upriver.
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The Sechura Desert is a coastal desert located south of the Piura Region of Peru along the Pacific Ocean coast and inland to the foothills of the Andes Mountains. Its extreme aridity is caused by the upwelling of cold coastal waters and subtropical atmospheric subsidence, but it is also subject to occasional flooding during El Niño years. In 1728, the town of Sechura was destroyed by a tsunami and was later rebuilt in its present location. In 1998, runoff from flooding rivers caused the formation of a temporary lake some long filling the Bayóvar Depression.
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She has continued to work on these relationships, concentrating on the subpolar North Atlantic and Southern Ocean as areas of particular importance. The sequestration of carbon through the biological pump in these regions may be an important regulatory of the global ocean system, but the dynamics of the nitrogen- phytoplankton system limit its efficiency. Much of Fawcett's works is based on measurements of stable nitrogen isotopes. Fawcett is also addressing the lack of research in the Benguela Upwelling System, which is important for the biodiversity and economy of the region.
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A sheet of aufeis in a glacial valley in Mongolia Aufeis accumulates during winter along stream and river valleys in arctic and subarctic environments. It forms by upwelling of river water behind ice dams, or by ground-water discharge. The latter mechanism prevails in high-gradient alpine streams as they freeze solid. Ground-water discharge is blocked by ice, perturbing the steady-state condition and causing a small incremental rise in the local water table until discharge occurs along the bank and over the top of the previously formed ice.
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Seabird species include tufted puffins, the endangered short-tailed albatross, spectacled eider, and red-legged kittiwakes. Many of these species are unique to the area, which provides highly productive foraging habitat, particularly along the shelf edge and in other nutrient-rich upwelling regions, such as the Pribilof, Zhemchug, and Pervenets canyons. The Bering Sea is also home to colonies of crested auklets, with upwards of a million individuals. Two Bering Sea species, the Steller's sea cow (Hydrodamalis gigas) and spectacled cormorant (Phalacrocorax perspicillatus), are extinct because of overexploitation by man.
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Charleston Bump (National Oceanic and Atmospheric Administration) The Charleston Bump is a deepwater rocky ocean bottom feature approximately 90 miles (140 km) southeast of Charleston, South Carolina. The Bump, rising from the Blake Plateau, lies in the path of the Gulf Stream and deflects the Gulf Stream offshore away from the coast of the eastern United States. This deflection amplifies downstream eddies and gyres and enhances upwelling of nutrient rich waters onto the continental shelf. These nutrient inputs support an ecosystem of plankton, fish, and other sea life.
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Marine stratocumulus is a type of stratocumulus cloud that form in the stable air off the west coast of major land masses. The Earth spins on its axis, which results in the Coriolis force pushing the ocean surface water away from the coast in the mid-latitudes. This results in upwelling of cold water from below that creates a pool of cool water at the surface, which in turn cools the air directly above it. The surface cooling results in a large temperature inversion at the top of the marine layer.
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In these carbonate factories, precipitation is biotically controlled by heterotrophic organisms, sometimes in association with photo-autotrophic organisms such as red algae. The typical skeletal association includes foraminifers, red algae and molluscs. Despite being autotrophic, red algae are mostly associated to heterotrophic carbonate producers, and need less light than green algae. The range of occurrence of cool-water factories extends from the limit of the tropical factory (at about 30◦) up to polar latitudes, but they could also occur at low latitudes in the thermocline below the warm surface waters or in upwelling areas.
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The chain has been produced by the movement of the ocean crust over the Hawaii hotspot, an upwelling of hot rock from the Earth's mantle. As the oceanic crust moves the volcanoes farther away from their source of magma, their eruptions become less frequent and less powerful until they eventually cease to erupt altogether. At that point erosion of the volcano and subsidence of the seafloor cause the volcano to gradually diminish. As the volcano sinks and erodes, it first becomes an atoll island and then an atoll.
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Occasionally also termed "Cool-summer Mediterranean climate", this subtype of the Mediterranean climate (Csb) is a less common form of the Mediterranean climate. As stated earlier, regions with this subtype of the Mediterranean climate experience warm (but not hot) and dry summers, with no average monthly temperatures above during its warmest month and an average in the coldest month between or, in some applications, between . Also, at least four months must average above . Cool ocean currents and upwelling are often the reason for this cooler type of Mediterranean climate.
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The reason for this was discovered upon analyzing data from the USARRAY project. It was found that the asthenosphere had invaded the overlying lithosphere, as a result of an area of mantle upwelling stemming from either the disintegration of the descending Farallon Plate, or the survival of the subducted spreading center connected to the East Pacific Rise and Gorda Ridge beneath western North America, or possibly both. The asthenosphere erodes the lower levels of the Plateau. At the same time, as it cools, it expands and lifts the upper layers of the Plateau.
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Panthalassa was a hemisphere-sized ocean, much larger than the modern Pacific. It could be expected that the large size would result in relatively simple ocean current circulation patterns, such as a single gyre in each hemisphere, and a mostly stagnant and stratified ocean. Modelling studies, however, suggest that an east-west sea surface temperature (SST) gradient was present in which the coldest water was brought to the surface by upwelling in the east while the warmest water extended west into the Tethys Ocean. Subtropical gyres dominated the circulation pattern.
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When a plate of oceanic crust is subducted beneath an overriding plate of oceanic crust, as the underthrusting crust melts, it can cause upwelling of magma that can cause volcanism along the subduction front on the overriding plate. This produces an oceanic chain of volcanoes, like Japan. This volcanism causes metamorphism of rocks, intrusions of magma that produce rocks such as granite, and thickens the crust by depositing additional layers of rock from volcanoes. This tends to make the crust lighter and thicker, as a result making it immune to subduction.
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Some of these changes are forced externally, such as the seasonal shift of the Sun into the Northern Hemisphere in summer. Other changes appear to be the result of coupled ocean- atmosphere feedback in which, for example, easterly winds cause the sea surface temperature to fall in the east, enhancing the zonal heat contrast and hence intensifying easterly winds across the basin. These enhanced easterlies induce more equatorial upwelling and raise the thermocline in the east, amplifying the initial cooling by the southerlies. This coupled ocean- atmosphere feedback was originally proposed by Bjerknes.
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On top of this gradual trend is overprinted the signal of Milankovic cycles, which ultimately trigger the switch between P- and S- episodes. These events become longer during the Devonian; the enlarging land plant biota probably acted as a large buffer to carbon dioxide concentrations. The end-Ordovician Hirnantian event may alternatively be a result of algal blooms, caused by sudden supply of nutrients through wind-driven upwelling or an influx of nutrient-rich meltwater from melting glaciers, which by virtue of its fresh nature would also slow down oceanic circulation.
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Although persistent wind shear and dry air hampered intensification early on, Carlos strengthened into a hurricane on June 13 after moving into a more favorable environment. However, the return of dry air and upwelling of cooler waters caused the system to deteriorate into a tropical storm. Paralleling the Mexican coast, Carlos later regained hurricane intensity on June 15 and attained peak winds of 90 mph (150 km/h) a day later. The reprieve was brief, however, as the onset of wind shear, land interaction, and dry air afterward led to rapid weakening.
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However, the storm began to weaken due to increasing wind shear, drier air, and upwelling of cold water, caused by Debby's slow movement. It was initially composed of multiple small swirls, but consolidated into one well-defined low-level circulation by early on June 25. Due to its excessively slow movement and no prediction for acceleration, the National Hurricane Center remarked that, "the cyclone does not seem to be going anywhere anytime soon." A burst in deep convection occurred later on June 25, though adverse environmental conditions prevented re-intensification.
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Unlike other rivers that empty into the sea, the Congo River is not building a delta because essentially all of its sediments are carried by turbidity currents via the submarine canyon to the fan. This accumulation is probably the greatest in the world for a currently active submarine system. The fan is built up by sediment gravity flows and other submarine mass movements, but also represents a very large active turbidite system. Although there exists a net up-canyon bottom current due to upwelling, these events overwhelm the normal bottom flow and ensure continued deposition.
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WHOI scientists at LJL installing a Video Plankton RecorderThis nutrient rich upwelling such as occurs in the Gulf of Panama, can stimulate Plankton production leading to blooms of centric, colonial, and penate diatoms and dinoflagellates. Zooplankton populations often respond to this by subsequently increasing growth and reproduction rates. Scientists are now able to quantify the abundance and diversity of these microscopic organisms in-situ with sensors such as the Video Plankton Recorder (a specialized underwater microscope and imaging system).Davis, CS, Hu, Q, SM Gallager, x Tang, C Ashjian.
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A rip current can occur when water piles up near the shore from advancing waves and is funnelled out to sea through a channel in the seabed. It may occur at a gap in a sandbar or near a man-made structure such as a groyne. These strong currents can have a velocity of per second, can form at different places at different stages of the tide and can carry away unwary bathers. Temporary upwelling currents occur when the wind pushes water away from the land and deeper water rises to replace it.
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As the mantle rises it cools and melts, as the pressure decreases and it crosses the solidus. The amount of melt produced depends only on the temperature of the mantle as it rises. Hence most oceanic crust is the same thickness (7±1 km). Very slow spreading ridges (<1 cm·yr−1 half-rate) produce thinner crust (4–5 km thick) as the mantle has a chance to cool on upwelling and so it crosses the solidus and melts at lesser depth, thereby producing less melt and thinner crust.
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It moved slowly over waters it traversed just four days prior, causing upwelling; this is the process in which a stationary storm causes the water temperatures to decrease by bringing the cooler, deeper waters to the surface. As a result, Jeanne weakened to a minimal hurricane midday on September 23, though it was forecast to re- intensify and attain major hurricane status. By early on September 24, the winds had decreased to 80 mph (130 km/h); its convection weakened in intensity, and the eyewall eroded due to dry air entrainment.
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Diagram of a mid-ocean ridge showing ridge push near the mid-ocean ridge and the lack of ridge push after 90 Ma Ridge push is the result of gravitational forces acting on the young, raised oceanic lithosphere around mid-ocean ridges, causing it to slide down the similarly raised but weaker asthenosphere and push on lithospheric material farther from the ridges. Mid-ocean ridges are long underwater mountain chains that occur at divergent plate boundaries in the ocean, where new oceanic crust is formed by upwelling mantle material as a result of tectonic plate spreading and relatively shallow (above ~60 km) decompression melting. The upwelling mantle and fresh crust are hotter and less dense than the surrounding crust and mantle, but cool and contract with age until reaching equilibrium with older crust at around 90 Ma. This produces an isostatic response that causes the young regions nearest the plate boundary to rise above older regions and gradually sink with age, producing the mid-ocean ridge morphology. The greater heat at the ridge also weakens rock closer to the surface, raising the boundary between the brittle lithosphere and the weaker, ductile asthenosphere to create a similar elevated and sloped feature underneath the ridge.
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A trough of low pressure in the central Gulf of Mexico developed into Tropical Storm Debby at 1200 UTC on June 23, while located about south-southeast of the mouth of the Mississippi River. Despite a projected track toward landfall in Louisiana or Texas, the storm headed the opposite direction, moving slowly north-northeast or northeastward. It steadily strengthened, and at 1800 UTC on June 25, the storm attained its peak intensity with maximum sustained winds of 65 mph (100 km/h) and a minimum barometric pressure of 990 mbar (29 inHg). Dry air, westerly wind shear, and upwelling prevented further intensification.
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Polybius henslowii is a capable swimmer, and can be found swimming near the ocean surface, where it feeds on a mixture of squid, fish, and other crustaceans, including specimens of the same species . Indeed, P. henslowii has been observed to form pelagic swarms. These swarms are mostly composed of females, excluding that aggregations are for mating, while they might be related to feeding . When they swim inshore, along the coastal upwelling areas of Galicia (NW Spain), they rely more on benthic prey, such as polychaetes and detritus and are influenced by terrestrial organic matter coming from the rivers .
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It has been estimated that 70% of global wind energy is transferred to the ocean and takes place within the Antarctic Circumpolar Current (ACC). Eventually, upwelling due to wind-stress transports cold Antarctic waters through the Atlantic surface current, while warming them over the equator, and into the Arctic environment. Thus, warming in the Arctic depends on the efficiency of the global ocean transport and plays a role in the polar see-saw effect. Decreased oxygen and low-pH during La Niña are processes that correlate with decreased primary production and a more pronounced poleward flow of ocean currents.
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Erlandson et al. (2007) suggest that coastal migrations and settlements happened in higher latitudes, such as 35-70°N, where coastal ecosystems would be more productive because of geography and upwelling in the Northern Pacific Rim. The different kelps of the Pacific Rim are major contributors to the areas of productivity and biodiversity and support a wide variety of life such as marine mammals, shellfish, fish, seabirds, and edible seaweeds that would also support a coastal community of hunter-gatherers. While the benefits of kelp forests are very clear in the present day Pacific Rim, Erlandson et al.
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The site suffers from a host of threats, including collapse of ancient structures, erosion from flooding and improper rainwater drainage, weathering from salt upwelling, improper restoration of ancient structures and unsustainable tourism. The last has increased substantially, especially since the site received widespread media coverage in 2007 during the New7Wonders of the World Internet and cellphone campaign. In an attempt to reduce the impact of these threats, the Petra National Trust (PNT) was established in 1989. It has worked with numerous local and international organisations on projects that promote the protection, conservation, and preservation of the Petra site.
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One way to increase the carbon sequestration efficiency of the oceans is to add micrometre-sized iron particles in the form of either hematite (iron oxide) or melanterite (iron sulfate) to certain regions of the ocean. This has the effect of stimulating growth of plankton. Iron is an important nutrient for phytoplankton, usually made available via upwelling along the continental shelves, inflows from rivers and streams, as well as deposition of dust suspended in the atmosphere. Natural sources of ocean iron have been declining in recent decades, contributing to an overall decline in ocean productivity (NASA, 2003).
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One is upwelling at the periphery; the other is the convective mixing caused by the cooling of surface water as the ring moves north of the current. The thermostad is the deep mixed layer that has discrete boundaries and uniform temperature. Within this layer, nutrient-rich water is brought to the surface, which generates a burst of primary production. Given that the water in the core of a ring has a different temperature regime than the shelf waters, there are times when a warm-core ring is undergoing its spring bloom while the surrounding shelf waters are not.
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E. Linacre and B. Geerts. Movement of the South Pacific convergence zone Retrieved on 2006-11-26. The southern ITCZ in the southeast Pacific and southern Atlantic, known as the SITCZ, occurs during the Southern Hemisphere fall between 3° and 10° south of the equator east of the 140th meridian west longitude during cool or neutral El Niño–Southern Oscillation (ENSO) patterns. When ENSO reaches its warm phase, otherwise known as El Niño, the tongue of lowered sea surface temperatures due to upwelling off the South American continent disappears, which causes this convergence zone to vanish as well.
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The relatively thin crust and short lifespan of the Aegir Ridge is anomalous given its proximity to the Iceland hotspot. Mantle hotspots deliver warm, actively-upwelling material to mid-ocean ridges, increasing mantle melting and crustal production. Likely, the stresses associated with plate tectonics and the mechanical structure of the lithosphere created a situation in which spreading at the Kolbeinsey Ridge was energetically favorable to spreading at the Aegir Ridge. As the Kolbeinsey Ridge began rifting, hotspot material would then draw out of the Aegir Ridge and flow preferentially towards the Kolbeinsey Ridge, leading to the ultimate extinction of the spreading center.
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Juvenile preparing to receive food from parent The California least tern hunts primarily in shallow estuaries and lagoons, or beyond the breakers, even beyond 24 km offshore in areas of upwelling, and where smaller fishes are abundant. They hover until spotting prey, and then plunge into the water without full submersion to extract prey. In the bays and lagoons of Southern California and northern Mexico, the favored prey include anchovy, smelt, silversides, shiner surfperch and small crustaceans. The terns often feed near shore in the open ocean, especially in proximity to lagoons or bay mouths (Baird 2010).
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The Findlater jet, a narrow low-level, atmospheric jet, also develops during the Southwest monsoon, and blows diagonally across the Indian Ocean, parallel to the coasts of Somalia and Oman. As a result, an Ekman transport is created to the right of the wind. At the center of the jet, the transport is maximum and decreases to the right and left with increasing distance. To the left of the jet center, there is less water movement toward the center than is leaving, creating a divergence in the upper layer and resulting in an upwelling event (Ekman suction).
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At the mouth of rivers where fresh water mixes with salt water, energy associated with the salinity gradient can be harnessed using pressure-retarded reverse osmosis process and associated conversion technologies. Another system is based on using freshwater upwelling through a turbine immersed in seawater, and one involving electrochemical reactions is also in development. Significant research took place from 1975 to 1985 and gave various results regarding the economy of PRO and RED plants. It is important to note that small-scale investigations into salinity power production take place in other countries like Japan, Israel, and the United States.
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The European bass, a common sight near the islands The Berlengas archipelago is situated off of Peniche, south of the Nazaré Canyon and on the edge of the continental shelf (in Farilhões Islets) on a maritime zone known by its relatively high biological productivity, acting as a meeting point between coastal and oceanic fish species. On the other hand, the upwelling currents originating in deep waters contribute to the development of an aquatic fauna with evident commercial interest. Its variety of fish and marine mammals, marine plants and other marine organisms as led to its classification as a marine reserve.
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Beneath the Superswell, a region of upwelling has been identified in the mantle, although the scarcity of seismic stations in the regions make it difficult to reliably image it. In the case of Macdonald, it seems like a low velocity anomaly in the mantle rises from another anomaly at depth to the surface. This has been explained by the presence of a "superplume", a very large mantle plume which also formed oceanic plateaus during the Cretaceous, with present-day volcanism at the Society and Macdonald volcanoes originating from secondary plumes that rise from the superplume to the crust.
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In Cape May, New Jersey, since the 1940s water withdrawals have lowered groundwater levels by up to 30 meters, reducing the water table to below sea level and causing widespread intrusion and contamination of water supply wells. Groundwater extraction can also lead to well contamination by causing upwelling, or upcoming, of saltwater from the depths of the aquifer. Under baseline conditions, a saltwater wedge extends inland, underneath the freshwater because of its higher density. Water supply wells located over or near the saltwater wedge can draw the saltwater upward, creating a saltwater cone that might reach and contaminate the well.
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Tropical cyclones also help maintain the global heat balance by moving warm, moist tropical air to the middle latitudes and polar regions, and by regulating the thermohaline circulation through upwelling. The storm surge and winds of hurricanes may be destructive to human-made structures, but they also stir up the waters of coastal estuaries, which are typically important fish breeding locales. Tropical cyclone destruction spurs redevelopment, greatly increasing local property values. When hurricanes surge upon shore from the ocean, salt is introduced to many freshwater areas and raises the salinity levels too high for some habitats to withstand.
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The project involved participants from Oregon State University (OSU), the University of North Carolina at Chapel Hill (UNC) and the Lamont-Doherty Earth Observatory (LDEO). The Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) program has also collected data through moorings and played a large role in expanding knowledge of the Oregon upwelling system of the inner shelf. One area of research still relatively unexplored is the impacts of biological and physical processes in the formation of hypoxic water in this area. Most of the research of hypoxic events were conducted after 2002, but much remains unknown.
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The concept envisions using artificial upwelling and floating, submerged platforms as substrate to replicate natural seaweed ecosystems that provide habitat and the basis of a trophic pyramid for marine life. Following the principles of permaculture, seaweeds and fish can be sustainably harvested while sequestering atmospheric carbon. As of 2020, a number of successful trials have taken place in Hawaii, the Philippines, Puerto Rico and Tasmania. The idea has received substantial public attention, notably featuring as a key solution covered by Damon Gameau’s documentary 2040 and in the book Drawdown: The Most Comprehensive Plan Ever Proposed to Reverse Global Warming edited by Paul Hawken.
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Thus, the northern fur seal and the South American sea lion tend to herd specific harem- associated females, occasionally injuring them, while the Steller sea lion and the New Zealand sea lion control spatial territories, but do not generally interfere with the movement of the females. Otariids are carnivorous, feeding on fish, squid and krill. Sea lions tend to feed closer to shore in upwelling zones, feeding on larger fish, while the smaller fur seals tend to take longer, offshore foraging trips and can subsist on large numbers of smaller prey items. They are visual feeders.
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A half dynamo cycle corresponds to a single sunspot solar cycle. At solar maximum, the external poloidal dipolar magnetic field is near its dynamo-cycle minimum strength, but an internal toroidal quadrupolar field, generated through differential rotation, is near its maximum strength. At this point in the dynamo cycle, buoyant upwelling within the convective zone forces emergence of a toroidal magnetic field through the photosphere, giving rise to patches of concentrated magnetic field corresponding to sunspots. During the solar cycle’s declining phase, energy shifts from the internal toroidal magnetic field to the external poloidal field, and sunspots diminish in number.
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L. celtica are suspension feeders that take in organic particles that fall from the photic zone. Shelf-break upwelling and water turbulence increases the transportation of organic matter up the water column, leading to high-concentrations of crinoids like L. celtica that feed on organic matter around these shelf breaks. The species plays an important role in marine environments by taking in large amounts of organic particles and regulating food chain production. For this reason, the presence of benthopelagic fish alongside crinoids like L. celtica can serve as indicators of highly productive regions of shelf-breaks.
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The South Pacific Gyre. Earth’s trade winds and Coriolis force cause the ocean currents in South Pacific Ocean to circulate counter clockwise. The currents act to isolate the center of the gyre from nutrient upwelling and few nutrients are transported there by the wind (eolian processes) because there is relatively little land in the Southern Hemisphere to supply dust to the prevailing winds. The low levels of nutrients in the region result in extremely low primary productivity in the ocean surface and subsequently very low flux of organic material settling to the ocean floor as marine snow.
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Temperatures of have been estimated for the lava erupted by the Black Tank cone. The magma erupted in the field ultimately appears to originate from the lithospheric or asthenospheric mantle with little contribution of crustal components, unlike earlier felsic volcanism. Upwelling of asthenosphere material appears to be responsible for the volcanism at the end, possibly associated with the change in the tectonics of the region from subduction-dominated to tectonics of a transform boundary. Fractional crystallization, magma ponding in the crust, differences in the mantle sources and partial melting processes have been invoked to explain certain compositional differences in the erupted rocks.
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Computer models of ocean circulation increasingly place most of the deep upwelling in the Southern Ocean, associated with the strong winds in the open latitudes between South America and Antarctica. While this picture is consistent with the global observational synthesis of William Schmitz at Woods Hole and with low observed values of diffusion, not all observational syntheses agree. Recent papers by Lynne Talley at the Scripps Institution of Oceanography and Bernadette Sloyan and Stephen Rintoul in Australia suggest that a significant amount of dense deep water must be transformed to light water somewhere north of the Southern Ocean.
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Some of the bottom water spreads through a gap to fill the South Sandwich Trench. Because of upwelling the new Weddell Sea Bottom Water turns clockwise west of 20°W and are a mixture of shelf water and a part of the Circumpolar Deep Water that follows the southern part of the gyre to the west. East, another part of the Circumpolar Deep Water mixes with shelf water and may establish a particular source of Weddell Sea Deep Water. In the Weddell Sea Deep Water, there is a 2 gyre cyclonic system inferred and is able to spill over the South Scotia Ridge.
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The circulation patterns in the upper mesosphere and thermosphere of Venus are completely different from those in the lower atmosphere. At altitudes 90–150 km the Venusian air moves from the dayside to nightside of the planet, with upwelling over sunlit hemisphere and downwelling over dark hemisphere. The downwelling over the nightside causes adiabatic heating of the air, which forms a warm layer in the nightside mesosphere at the altitudes 90–120 km. The temperature of this layer—230 K (−43 °C)—is far higher than the typical temperature found in the nightside thermosphere—100 K (−173 °C).
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Antarctic Convergence The Antarctic Convergence or Antarctic Polar Front is a curve continuously encircling Antarctica, varying in latitude seasonally, where cold, northward-flowing Antarctic waters meet the relatively warmer waters of the Subantarctic. Antarctic waters predominantly sink beneath the warmer subantarctic waters, while associated zones of mixing and upwelling create a zone very high in marine productivity, especially for Antarctic krill. This line, like the arctic tree line, is a natural boundary rather than an artificial one, such as the borders of nations and time zones. It not only separates two hydrological regions, but also separates areas of distinctive marine life and climates.
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Higher elevations are made temperate by their altitude, and the Arabian Sea coastline can receive surprisingly cool, humid breezes in summer due to cold upwelling offshore. The peninsula has no thick forests. Desert-adapted wildlife is present throughout the region. According to NASA's Gravity Recovery and Climate Experiment (GRACE) satellite data (2003–2013) analysed in a University of California, Irvine (UCI)-led study published in Water Resources Research on 16 June 2015, the most over-stressed aquifer system in the world is the Arabian Aquifer System, upon which more than 60 million people depend for water.
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Most phytoplankton need sunlight and nutrients from the ocean to survive, so they thrive in areas with large inputs of nutrient rich water upwelling from the lower levels of the ocean. Most coccolithophores, only require sunlight for energy production and have a higher ratio of nitrate uptake over ammonium uptake (nitrogen is required for growth and can be used directly from nitrate but not ammonium). Because of this they thrive in still, nutrient-poor environments where other phytoplankton are starving. Trade-offs associated with these faster growth rates, however, include a smaller cell radius and lower cell volume than other types of phytoplankton.
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Western- central Pacific westerly winds from El Nino force westward moving-equatorial Rossby waves and eastward currents that hit eastern New Guinea and propagate around the west coast as coastal Kelvin waves and down through the ITF along the west Australia Shelf coast serving to reduce the ITF. Upwelling (i.e. reduced sea level) associated with Rossby waves on the Pacific side reduces the Pacific-to-Indian pressure gradient and reduces the ITF. Interannual variability of Indian Ocean westerlies acts in the same manner as the seasonal equatorial Kelvin waves to reduce the normal westward ITF flow as well.
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The production of new seafloor and oceanic lithosphere results from mantle upwelling in response to plate separation. The melt rises as magma at the linear weakness between the separating plates, and emerges as lava, creating new oceanic crust and lithosphere upon cooling. The first discovered mid-ocean ridge was the Mid-Atlantic Ridge, which is a spreading center that bisects the North and South Atlantic basins; hence the origin of the name 'mid-ocean ridge'. Most oceanic spreading centers are not in the middle of their hosting ocean basis but regardless, are traditionally called mid-ocean ridges.
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Maximum tidal range at Simon's Town is 2.0 m at highest astronomical tide, with minimum range of about 0.56 m at mean neap tides. When large waves break at Macassar on a high tide the beach is known to be dangerous for swimming and beach erosion is increased. The circulation patterns of False Bay are variable over time, with seasonal and longer term cycles. There are cold-water upwelling events associated with south-easterly winds in summer, and periodic intrusions of warm water eddies from the Agulhas Current of the south coast, both of which contribute to the biodiversity.
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A hornito on the island of Réunion An example of a hornito on Hawaii that has built lava spatter deposits into a mound over its vent Hornitos are conical structures built up by lava ejected through an opening in the crust of a lava flow. Hornitos are similar to spatter cones but are rootless, meaning they were once a source of lava but that source was not directly associated with a true vent or magma source. They are usually created by the slow upwelling of lava through the roof of a lava tube. High pressure causes lava to ooze and spatter out.
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Like most large igneous provinces, the Mackenzie Large Igneous Province has its origins in a mantle plume--an upwelling zone of abnormally hot rock within the Earth's mantle. As the head of the Mackenzie plume encountered the Earth's lithosphere, it spread out and melted catastrophically to form large volumes of basaltic magma. This resulted in the creation of a stationary volcanic zone west of Victoria Island that experienced considerable volcanism known as the Mackenzie hotspot. Evidence for the Mackenzie hotspot include the existence of the giant mafic Mackenzie dike swarm because of its fanning pattern adjacent to the Muskox intrusion.
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Ice sheets have been observed to form later, separate earlier, and rapidly decline in age, thickness distribution and regional coverage. The ice in the Southern Beaufort Sea separates 7 weeks earlier than it used to during 1964 to 1974. An instance of climate change contributing to ice loss was the 13th most extreme Arctic storm recorded that impacted sea ice in the Beaufort and Chuckchi seas. In 2012, a cyclone had formed over Siberia and ended in the Canadian Arctic Archipelago during a period where large wave generation, oceanic upwelling, and mechanical forcing affected the ocean and its covering ice sheets.
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Their surfaces are heavily cratered, though all of them (except Umbriel) show signs of endogenic resurfacing in the form of lineaments (canyons) and, in the case of Miranda, ovoid race-track like structures called coronae. Extensional processes associated with upwelling diapirs are likely responsible for the origin of the coronae. Ariel appears to have the youngest surface with the fewest impact craters, while Umbriel's appears oldest. A past 3:1 orbital resonance between Miranda and Umbriel and a past 4:1 resonance between Ariel and Titania are thought to be responsible for the heating that caused substantial endogenic activity on Miranda and Ariel.
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The oceans are normally a natural carbon sink, absorbing carbon dioxide from the atmosphere. Because the levels of atmospheric carbon dioxide are increasing, the oceans are becoming more acidic. The potential consequences of ocean acidification are not fully understood, but there are concerns that structures made of calcium carbonate may become vulnerable to dissolution, affecting corals and the ability of shellfish to form shells. A report from NOAA scientists published in the journal Science in May 2008 found that large amounts of relatively acidified water are upwelling to within four miles of the Pacific continental shelf area of North America.
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The accommodation of this plate configuration results in a transform boundary along the Mendocino Fracture Zone, and a divergent boundary at the Gorda Ridge. Due to the relative plate motions, the triple junction has been migrating northwards for the past 25–30 million years, and assuming rigid plates, the geometry requires that a void, called slab window, develop southeast of the MTJ. At this point, removal of the subducting Gorda lithosphere from beneath North America causes asthenospheric upwelling. This instigates different tectonic processes, which include surficial uplift, crustal deformation, intense seismic activity, high heat flow, and even the extrusion of volcanic rocks.
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The Convincing Ground massacre, which took place near Portland, Victoria in 1829, arose over a dispute between European whalers and the Gunditjmara people over ownership of a beached whale.Ian D. Clark, pp17-22, Scars on the Landscape. A Register of Massacre sites in Western Victoria 1803-1859, Aboriginal Studies Press, 1995 Excerpt also published on Museum Victoria website , accessed 26 November 2008 Beginning in the mid-1840s, whaling and sealing were established as organized industries off the Bonney Coast. Today, southern rock lobster (referred to locally as crayfish) and trawling are the most important fishing industries in the Bonney Upwelling.
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Degree-1 mantle convection is a convective process in which one hemisphere is dominated by an upwelling, while the other hemisphere is downwelling. Some of the evidence is the abundance of extensive fracturing and igneous activity of late Noachian to early Hesperian age. A counter argument to the endogenic hypothesis is the possibility of those tectonic events occurring in the Borealis Basin due to the post-impact weakening of the crust. In order to further support the endogenic origin hypothesis geologic evidence of faulting and flexing of the crust prior to the end of the primordial bombardment is needed.
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Globigerina bulloides is a species of heterotrophic planktonic foraminifer with a wide distribution in the photic zone of the world's oceans. It is able to tolerate a range of sea surface temperatures, salinities and water densities, and is most abundant at high southern latitudes (up to 40° S), certain high northern latitudes (up to 80° N), and in low-latitude upwelling regions. The density or presence of G. bulloides may change as a function of phytoplankton bloom successions,NOAA National Geophysical Data Center: . and they are known to be most abundant during winter and spring months.
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Seamounts are exceptionally important to their biome ecologically, but their role in their environment is poorly understood. Because they project out above the surrounding sea floor, they disturb standard water flow, causing eddies and associated hydrological phenomena that ultimately result in water movement in an otherwise still ocean bottom. Currents have been measured at up to 0.9 knots, or 48 centimeters per second. Because of this upwelling seamounts often carry above-average plankton populations, seamounts are thus centers where the fish that feed on them aggregate, in turn falling prey to further predation, making seamounts important biological hotspots.
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Upwelling of itself due to its quasi-stationary movement combined with moderate wind shear hindered significant intensification of Kammuri over the next three days as it moved into the Philippine Area of Responsibility, with PAGASA subsequently assigning the typhoon the name Tisoy. Kammuri began to show signs of rapid intensification again on December 1, ultimately intensifying to a Category 4 typhoon the next day. It made landfall at peak intensity on that day in the Bicol Region and began to weaken, weakening to a Category 3 typhoon that evening. On November 30, Kammuri produced possibly the record lowest known cloud top temperature at .
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As a result, its structure deteriorated, the eye fading and the surrounding cloud tops warming. A faraway mid-latitude ridge caused Sergio to turn towards the southwest from October 5–6. After bottoming out as a low- end Category 3 hurricane on October 5 at 06:00 UTC, Sergio began to intensify once more, reaching a secondary peak with winds of 125 mph (205 km/h) on October 6 at 00:00 UTC. After maintaining its intensity for 18 hours, the hurricane began to weaken around 00:00 UTC on October 7 due to upwelling and a third eyewall replacement cycle.
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A number of separate water masses surround Echo Bank, which originate from regions such as the North Atlantic, the South Atlantic and Antarctica and are stacked over each other. In general, the region is under the influence of the nutrient-poor waters of the subtropical gyre and the upwelling regions off northwestern Africa. Bottom net trawlings of Echo Bank have revealed remarkable findings such as a rich decapod fauna. African cuttlefish, the barnacle Poecilasma aurantia, the common cuttlefish, the elegant cuttlefish and the giant African cuttlefish occur at Echo Bank; the giant African cuttlefish is the most commercially important cuttlefish in the region.
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On October 2, the British ship Plainsman observed gale-force winds, prompting the NHC to upgrade the depression to Tropical Storm Fern. A small system, the storm intensified further to hurricane status on October 3, reaching peak winds of 85 mph (140 km/h) and a minimum barometric pressure of . Upwelling and cold air left in the wake of Hurricane Beulah caused Fern to weaken slightly as it approached the Gulf Coast of Mexico. Around 06:00 UTC on October 4, Fern made landfall about 30 mi (50 km) north of Tampico, Tamaulipas, possibly having weakened to a tropical storm.
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Some details of Cloud's original model were abandoned. For example, improved dating of Precambrian strata has shown that the late Archean peak of BIF deposition was spread out over tens of millions of years, rather than taking place in a very short interval of time following the evolution of oxygen- coping mechanisms. However, his general concepts continue to shape thinking about the origins of banded iron formations. In particular, the concept of the upwelling of deep ocean water, rich in reduced iron, into an oxygenated surface layer poor in iron remains a key element of most theories of deposition.
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One example of the effects of lithosphere delamination is seen in the Sierra Nevada (US)², Basin and Range Province and Colorado Plateau in the western USA. During crustal extension in the Basin and Range Province 10 million years ago, the upwelling of asthenosphere thinned the lithosphere. Heating caused by the rise of the warmer asthenosphere created a crustal lower-viscosity zone and delamination occurred on the flanks of the Basin and Range. Uplift of the Sierra Nevada mountain range in California and the Colorado Plateau has occurred on the flanks as a result of the loss of high density lower lithosphere.
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Eddies from the warm South Indian Ocean Agulhas current along South Africa's east coast do round the Cape of Good Hope from time to time to join the Bengulela current. The Benguela current is 200 to 300 km wide and widens further as it flows north and northwest. Its western, seaward edge is well-defined, with many temporary and seasonal eddies and meanders. There is however a well-defined thermal front between the waters associated with the Benguela Upwelling System and those of the eastward flowing Atlantic currents which are not deflected northward by the African continent.
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Similar to the Pacific El Niño, a thick slab of warm, nutrient poor water enters the northern part of the Benguela upwelling system off the Namibia coast about once per decade. During the Benguela Niño, warm, salty waters from the Angola Current move southward, from 15°S to as far as 25°S. This slab of warm salty water extends to 150 km offshore and to 50 m depth. Heavy rains, changes in fish abundance, and temporal proximity to the Pacific El Niño have been observed; however, the causes and effects of the Benguela Niño are not well understood.
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Large-scale oceanic circulation has a direct impact on opal deposition. The Pacific (characterized by nutrient poor surface waters, and deep nutrient rich waters) and Atlantic Ocean circulations, are favoring the production/preservation of silica and carbonate, respectively. For instance, Si/N and Si/P ratios increase from the Atlantic to the Pacific and Southern Ocean, favoring opal versus carbonate producers. Consequently, the modern configuration of large-scale oceanic circulation resulted in the localization of major opal burial zones in the Equatorial Pacific, in the eastern boundary current upwelling systems, and by far the most important, the Southern Ocean.
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The passive margin switched to active margin in the early-to-mid Mesozoic when the Farallon Plate under the Pacific Ocean started to dive below the North American Plate, creating a subduction zone; volcanoes and uplifting mountains were created as a result. Erosion over many millions of years created a relatively featureless plain. Stretching of the crust under western North America started around 16 Ma and is thought to be caused by upwelling from the subducted spreading-zone of the Farallon Plate. This process continues into the present and is thought to be responsible for creating the Basin and Range province.
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They can measure the spread of an ash plume, such as the one from Eyjafjallajökull's 2010 eruption, as well as SO2 emissions. InSAR and thermal imaging can monitor large, scarcely populated areas where it would be too expensive to maintain instruments on the ground. Other geophysical techniques (electrical, gravity and magnetic observations) include monitoring fluctuations and sudden change in resistivity, gravity anomalies or magnetic anomaly patterns that may indicate volcano-induced faulting and magma upwelling. Stratigraphic analyses includes analyzing tephra and lava deposits and dating these to give volcano eruption patterns, with estimated cycles of intense activity and size of eruptions.
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About 2 billion years ago, a massive upwelling of molten magma resulted in what is now known as the Bushveld Igneous Complex. The enormous weight of this intrusion depressed the sediments that lay beneath and tilted the sediments along the edges so that the broken escarpments faced outward and upward, and the gentler dip slopes inward. During the same period, these sediments were fractured and igneous intrusions of dolerite filled the cracks. With the passage of time these intrusions eroded, especially on the dip slopes, forming deep kloofs or ravines providing rock-climbing potential to modern man.
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El Niño has the most direct impacts on life in the equatorial Pacific, its effects propagate north and south along the coast of the Americas, affecting marine life all around the Pacific. Changes in chlorophyll-a concentrations are visible in this animation, which compares phytoplankton in January and July 1998. Since then, scientists have improved both the collection and presentation of chlorophyll data. When El Niño conditions last for many months, extensive ocean warming and the reduction in easterly trade winds limits upwelling of cold nutrient-rich deep water, and its economic effect on local fishing for an international market can be serious.
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Coastal upwelling, river discharge, tidal mixing, estuarine circulation, climate oscillation, and remineralization, are sources or sinks for the Columbia River basin nutrient budget. Due to these transport processes the Columbia River Estuary provides large nutrient sources to the adjacent sub-arctic Northeast Pacific coastal surface water. Nitrogen is added to rivers through many natural processes, such as the decomposition of leaf litter and organic matter. Nitrogen gas is the most abundant molecule in earth's atmosphere, comprising about 78 percent of the total composition of air, however not typically a large source of nitrogen to the river.
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Due to coastal upwelling, ocean sources of nitrate (an oxidized form of nitrogen) exceed river sources by a magnitude of roughly 3 to 1, and is a primary source of nitrogen for the Columbia River Estuary. This is evident within the estuary by the positively correlated relationship of nitrate availability and salinity, the latter an identifying characteristic of highly saline marine waters. As a result of differences in delivery to the system, nitrate is the primary limiting nutrient in the estuary. Consequently, during seasonal periods of downwelling when less ocean water is mixed into the estuary, local nitrate concentrations may be very low.
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The significant decrease in pacific sardine population can be linked to the levels of nitrogen within their habitat, a limiting factor in plankton production. Pacific sardines in the California current system rely on wind driven upwelling to push cooler, nitrogen rich waters towards the surface, maintaining a sustainable, nutrient abundant environment. Continued environmental disruptions, such as El Niño, rising ocean temperatures, and increased commercial fishing, have drastic effects on nutrient cycling within the California current system, leading to lasting impacts on Pacific sardine productivity and reproductive success. The brown pelican has been predicted to have high vulnerability to declining sardine populations .
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Upwelling in coastal systems also promotes increased productivity by conveying deep, nutrient-rich waters to the surface, where the nutrients can be assimilated by algae. Examples of anthropogenic sources of nitrogen- rich pollution to coastal waters include seacage fish farming and discharges of ammonia from the production of coke from coal. The World Resources Institute has identified 375 hypoxic coastal zones in the world, concentrated in coastal areas in Western Europe, the Eastern and Southern coasts of the US, and East Asia, particularly Japan. Selman, Mindy (2007) Eutrophication: An Overview of Status, Trends, Policies, and Strategies.
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Modeling eddy development, as it relates to turbulence and fate transport phenomena, is vital in grasping an understanding of environmental systems. By understanding the transport of both particulate and dissolved solids in environmental flows, scientists and engineers will be able to efficiently formulate remediation strategies for pollution events. Eddy formations play a vital role in the fate and transport of solutes and particles in environmental flows such as in rivers, lakes, oceans, and the atmosphere. Upwelling in stratified coastal estuaries warrant the formation of dynamic eddies which distribute nutrients out from beneath the boundary layer to form plumes.
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This second episode of alkalic volcanism occurred along the eastern part of the graben in the early Cretaceous. The products of this event are the Monteregian Hills in Montérégie, Quebec. These are thought to have formed as a result of the North American Plate sliding westward over a long-lived center of upwelling magma called the New England hotspot, and is the eroded remnants of intrusive stocks. These intrusive stocks have been variously interpreted as the feeder intrusions of long extinct volcanoes, which would have been active about 125 million years ago, or as intrusives that never breached the surface in volcanic activity.
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Phytoplankton production is dramatically increased in these areas because the nutrient-rich water lying below the pycnocline is relatively close to the surface and is thus easily upwelled. Scientists at Scripps Institution of Oceanography said in 2011 that the average surface temperature of the water at Scripps Pier has increased by almost 3 degrees since 1950. The "Bakun upwelling index" is based on a 20-year average of the monthly mean Ekman transport for different regions off the California coast. It ranges from 300 meters-cubed/second (in the offshore direction) to −212 meters-cubed/second (toward the coast, or onshore direction).
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A model put forward by Lee Kump, Alexander Pavlov and Michael Arthur in 2005 suggests that oceanic anoxic events may have been characterized by upwelling of water rich in highly toxic hydrogen sulfide gas, which was then released into the atmosphere. This phenomenon would probably have poisoned plants and animals and caused mass extinctions. Furthermore, it has been proposed that the hydrogen sulfide rose to the upper atmosphere and attacked the ozone layer, which normally blocks the deadly ultraviolet radiation of the Sun. The increased UV radiation caused by this ozone depletion would have amplified the destruction of plant and animal life.
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The reef environment during the first stage of development was described as warm (around ), shallow, high energy, clear water that was free from debris and which had a normal salinity level of 27 to 40 ppt (parts per thousand). The basin water provided plenty of nutrients, since there was continuous upwelling of water that mixed newly brought marine water with anoxic water from the basin floor. The makeup of the reef is described as being built primarily from erect sponges, which have large, rigid skeletons, and abundant red algae, microbial micrite, and inorganic cement. The microbial micrite worked to trap sediment.
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Marine bioregions of the South African Exclusive Economic Zone: The Tsitsikamma Marine Protected Area is in the Agulhas bioregion. The MPA is in the warm temperate Agulhas inshore marine bioregion to the east of Cape Point which extends eastwards to the Mbashe River. The Mbashe River was chosen as the most appropriate boundary between the subtropical Natal province to the north, and the warm temperate Agulhas region to the south, but change is gradual between these regions. Upwelling on the south coast of South Africa is largely driven by the Agulhas current and the continental shelf.
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Pelagic fish aggregation near Isla Pacora, Liquid Jungle Lab WHOI scientist observing gelatinous zooplankton (Salp) in open ocean water near Coiba Current areas of marine research at the Liquid Jungle include plankton community dynamicsGallager, Scott M., A.D. York, C. Mingione and S. Lerner. Plankton community structure in the Gulf of Chiriqui, Pacific-Panama, as modulated by upwelling and large internal waves. (in prep) and marine larval ecology and transport,Starczak, Victoria, P. Perez-Brunius, J. Pineda, J. Gyory, and H. Levine. The role of season, salinity and flushing in determine barnacle distributions in tow adjacent mangrove coastal lagoons.
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The prevailing Brazil Current brings warm surface waters from the north, supporting a local reef fish population that is closer to the fauna of the tropical Western Atlantic and Northeastern Brazilian coast than the fauna of southern temperate reefs. A seasonal upwelling brings colder waters of up from the shelf slope to the deepest areas of the reef, where temperate species are found. The result is a fauna that ranges from that of tropical regions to subtropical endemics and species found as far south as Patagonia. 196 reef fish species have been recorded, in 124 genera and 66 families.
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Sargassum is a genus of brown (class Phaeophyceae) macroalgae (seaweed) in the order Fucales. Numerous species are distributed throughout the temperate and tropical oceans of the world, where they generally inhabit shallow water and coral reefs, and the genus is widely known for its planktonic (free-floating) species. Most species within the class Phaeophyceae are predominantly cold- water organisms that benefit from nutrients upwelling, but the genus Sargassum appears to be an exception. Any number of the normally benthic species may take on a planktonic, often pelagic existence after being removed from reefs during rough weather; however, two species (S.
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Ocean Thermal Energy Conversion (OTEC) uses the ocean thermal gradient between cooler deep and warmer shallow or surface seawaters to run a heat engine and produce useful work, usually in the form of electricity. OTEC can operate with a very high capacity factor and so can operate in base load mode. The denser cold water masses, formed by ocean surface water interaction with cold atmosphere in quite specific areas of the North Atlantic and the Southern Ocean, sink into the deep sea basins and spread in entire deep ocean by the thermohaline circulation. Upwelling of cold water from the deep ocean is replenished by the downwelling of cold surface sea water.
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Some of the drains originate from one-time watercress beds fed by clear chalk water springs and feed into either the Western Stream arising off the 'Sand Boils' or the Eastern Stream arising off Alexanders Moors. Both streams flow into Waltham Mill Pond and from where the water passes to The Moors Stream, a headwater of the River Hamble. The 'Sand Boils' is an area at the head of the West Stream in which upwelling spring water creates swirling sandy patches in the gravelly streambed. The Moors comprises the wetland area fed by springs and surface watercourses within the SSSI and adjacent land and which discharge into the Waltham Mill Pond.
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Tropical Storm Matthew developed on September 28 from a tropical wave moving through the southern Lesser Antilles. Low wind shear and warm waters favored strengthening, and the storm intensified into a hurricane on September 29. Early on October 1, following a period of rapid deepening, Matthew reached Category 5 on the Saffir–Simpson scale, with peak sustained winds of 270 km/h (165 mph) while north of the Colombia coast. Upwelling of cooler waters subsequently caused Matthew to weaken to a Category 4 hurricane. By October 3, the hurricane was moving northward through the Caribbean around the western periphery of a large ridge, while maintaining Category 4 intensity.
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At first the driving force for spreading was argued to be convection currents in the mantle. Since then, it has been shown that the motion of the continents is linked to seafloor spreading by the theory of plate tectonics, which is driven by convection that includes the crust itself as well. The driver for seafloor spreading in plates with active margins is the weight of the cool, dense, subducting slabs that pull them along, or slab pull. The magmatism at the ridge is considered to be passive upwelling, which is caused by the plates being pulled apart under the weight of their own slabs.
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In Southern Africa, the range is associated with cold currents up the western and southern coasts, ranging northwards as far as about 23°S due to the cold counter clockwise Benguela Current. The species has been found to occur year-round in a localized area on the southwestern coast of Namibia, in Lüderitz, linked to the strong Lüderitz upwelling cell area and high productivity waters. These animals may occasionally extend their range into South African waters although more sampling effort is needed to support this. Just one confirmed sighting of the species exists from the South African coast, just south of the Orange River.
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The Orcinus lineage, like many other predatory marine lineages, may have fished up the food chain and progressively evolved to eat bigger and bigger food items, with Pliocene killer whales able to hunt large fish, and the modern killer whale able to hunt large whales. Stockach is situated in the Molasse basin, which dates to the Early Miocene, and was submerged in the Western Paratethys Sea. The basin represents coastal waters and strong tidal currents, with an average depth of less than . Central Europe, at this time, probably represented an upwelling area along a continental shelf, which attracted a variety of sea life, including swarming fish.
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Other large marine animals found include ancient elephant seals, dugongs, sea turtles, ancient penguins such as Pseudaptenodytes, the extinct albatross Diomedea thyridata, and the extinct toothed seabirds of the genus Pelagornis. The South African teeth attributed as cf. Livyatan are from the Avontuur Member of the Alexander Bay Formation near the village of Hondeklip Bay, Namaqualand, which is also dated to around 5mya in the Pliocene. The Hondeklip Bay locality enjoys a rich heritage of marine fossils, whose diversity may have been thanks to the initiation of the Benguela Upwelling during the late Miocene, which likely provided large populations of phytoplankton traveling the cold nutrient-rich waters.
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Ridge push (also known as gravitational sliding) or sliding plate force is a proposed driving force for plate motion in plate tectonics that occurs at mid- ocean ridges as the result of the rigid lithosphere sliding down the hot, raised asthenosphere below mid-ocean ridges. Although it is called ridge push, the term is somewhat misleading; it is actually a body force that acts throughout an ocean plate, not just at the ridge, as a result of gravitational pull. The name comes from earlier models of plate tectonics in which ridge push was primarily ascribed to upwelling magma at mid-ocean ridges pushing or wedging the plates apart.
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However, no difference in the abundance of euphausiids, planktonic shrimp-like marine crustaceans, was found between areas of upwelling and warm-core eddies, but in 2004 the hyperiid abundance was found to be lower within Loop Current Eddies as opposed to outside. Concurrently, it was found that nutrient (nitrate) levels were low above 100 meters within warm-core eddies, while nitrate levels were high within cold features. Low standing stock of chlorophyll, primary production, and zooplankton biomass was found to be low in LCEs. Low chlorophyll concentrations and primary production are likely a result of low nutrients levels, as many planktonic species require nitrate and other nutrients to survive.
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The Attawapiskat kimberlite field is a field of kimberlite pipes located astride the Attawapiskat River in the Hudson Bay Lowlands, in Northern Ontario, Canada. It is thought to have formed about 180 million years ago in the Jurassic period when the North American Plate moved westward over a centre of upwelling magma called the New England hotspot, also referred to as the Great Meteor hotspot. Since June 26, 2008, the De Beers open pit Victor Diamond Mine has been in operation mining two pipes in the field at , about west of the community of Attawapiskat. The mine was expected to produce of diamonds a year.
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In August, 1978, a bloom stretched 100 km eastwards in Roaringwater Bay from Fastnet Rock to Kinsale Harbor in Irish waters. The next year at around the same time, a similar bloom appeared, and again in 1984. These blooms resulted in the deaths of benthic organisms as well as farmed culture and their consistency suggests the water zone between the upwelling open ocean and the more stratified inner bay might be favorable conditions for phytoplankton growth. The English Channel experienced a major bloom in 2003 that traveled from the western English Channel at end of June to the French coast of Brittany at the beginning of August.
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Estimated change in seawater alt=World map showing the varying change to pH across different parts of different oceans NOAA provides evidence for the upwelling of "acidified" water onto the Continental Shelf. In the figure above, note the vertical sections of (A) temperature, (B) aragonite saturation, (C) pH, (D) DIC, and (E) p on transect line 5 off Pt. St. George, California. The potential density surfaces are superimposed on the temperature section. The 26.2 potential density surface delineates the location of the first instance in which the undersaturated water is upwelled from depths of 150 to 200 m onto the shelf and outcropping at the surface near the coast.
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10°N latitude and not along the geographic equator. The reasons are the two cold currents: California Current at Northeast and Humboldt Current along the equatorial line. The Hawaiian Islands (in white) have higher temperatures than the equatorial line near the coast of South America because cold waters from upwelling along the California coast are farther away than the thermal equator, and therefore these cold waters warm up for several thousands of kilometres. The thermal equator (also known as "the heat equator") is a belt encircling the Earth, defined by the set of locations having the highest mean annual temperature at each longitude around the globe.
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The spot's prominence indicated that it was composed of high- altitude aerosols similar to those seen during the SL9 impact. Using near- infrared wavelengths and the IRTF, Glenn Orton and his team detected bright upwelling particles in the planet's upper atmosphere and using mid-infrared wavelengths, found possible extra emission of ammonia gas. The force of the explosion on Jupiter was thousands of times more powerful than the suspected comet or asteroid that exploded over the Tunguska River Valley in Siberia in June 1908. (This would be approximately 12,500–13,000 Megatons of TNT, over a million times more powerful than the bomb dropped on Hiroshima.).
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273 Mean heat flow is 65 mW/m2 over continental crust and 101 mW/m2 over oceanic crust. This is 0.087 watt/square metre on average (0.03 percent of solar power absorbed by Earth), but is much more concentrated in areas where the lithosphere is thin, such as along mid- ocean ridges (where new oceanic lithosphere is created) and near mantle plumes. Earth's crust effectively acts as a thick insulating blanket which must be pierced by fluid conduits (of magma, water or other) in order to release the heat underneath. More of the heat in Earth is lost through plate tectonics, by mantle upwelling associated with mid-ocean ridges.
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Amanda originated as a tropical wave that moved into the eastern Pacific on May 16\. It continued west, organizing into a tropical depression around 18:00 UTC on May 22 and further intensifying into a tropical storm a day later. After attaining hurricane strength at 12:00 UTC on May 24, the storm began a period of rapid intensification, peaking as high-end Category 4 hurricane with winds of 155 mph (250 km/h) within 24 hours; this made Amanda the strongest May tropical cyclone and second earliest major hurricane on record in the basin. As the system slowed to a crawl, cold water upwelling beneath it began a weakening trend.
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Julio originated from a tropical wave that moved off Africa on July 20, ultimately organizing into a tropical depression well southwest of Baja California by 00:00 UTC on August 4\. After intensifying into a tropical storm six hours later, it tracked west-northwest. Light northeasterly wind shear allowed the cyclone to reach hurricane strength around 06:00 UTC on August 6 and further organize to its peak as a Category 3 with winds of 120 mph (195 km/h) two days later, despite cool ocean temperatures. Shortly after entering the central Pacific, Julio began to weaken as a result of cold water upwelling.
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La Guaira Bank () is an underwater ridge that is approximately 12 miles off the coast from the city of La Guaira. The bank is approximately long from east to west and wide from north to south, and it rises from in the surrounding area to . The area provides the structure to deep-sea animals, and other organisms such as gorgonians, sponges, and coral, that require ocean currents to bring their food to them. Westerly currents flow off the coast of Venezuela, and the bank acts as a barrier to the current, creating an upwelling of nutrients to the ocean surface from deep-water stockpiles.
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Two moon jellyfish disturbing the pycnocline in the top water layer of Gullmarn fjord, Sweden A pycnocline is the cline or layer where the density gradient () is greatest within a body of water. An ocean current is generated by the forces such as breaking waves, temperature and salinity differences, wind, Coriolis effect, and tides caused by the gravitational pull of the Moon and the Sun. In addition, the physical properties in a pycnocline driven by density gradients also affect the flows and vertical profiles in the ocean. These changes can be connected to the transport of heat, salt, and nutrients through the ocean, and the pycnocline diffusion controls upwelling.1\.
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The reserve is located on an Atlantic island in the south east of the municipality of Arraial do Cabo, Rio de Janeiro. The upwelling of cold waters of the Malvinas Current near the island creates a seasonal semi-arid micro-climate and provides the conditions for dunes, hyper-saline lagoons and several endemic and unique communities of vegetation. It has been called the "Plant Diversity Center of Cabo Frio" and recognized by the World Wildlife Fund and International Union for Conservation of Nature. The island, also called the Ilha do Farol (Lighthouse Island), is accessible via boat by visitors to the beach of fine, white sand and the old lighthouse ruins.
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Ultimately, diatom cells in these resting populations re-enter the upper mixed layer when vertical mixing entrains them. In most circumstances, this mixing also replenishes nutrients in the upper mixed layer, setting the scene for the next round of diatom blooms. In the open ocean (away from areas of continuous upwelling), this cycle of bloom, bust, then return to pre-bloom conditions typically occurs over an annual cycle, with diatoms only being prevalent during the spring and early summer. In some locations, however, an autumn bloom may occur, caused by the breakdown of summer stratification and the entrainment of nutrients while light levels are still sufficient for growth.
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The Gulf of Tehuantepec is located on the Pacific coast of southern Mexico Gulf of Tehuantepec () is a large body of water on the Pacific coast of the Isthmus of Tehuantepec, southeastern Mexico, at . Many (but not all) Pacific hurricanes form in or near this body of water. A strong, gale-force wind called the Tehuano periodically blows out over the waters of the Gulf of Tehuantepec, inducing strong upwelling of nutrient-rich waters which support abundant sea life. The gulf is in the path of the lowest landform between Mexico and Northern Central America, allowing unhindered wind passage from the Gulf of Mexico, and the Eastern Pacific Ocean.
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A rift about long and wide, named the Alpha-Lada extensional belt, spans the northwestern edge of Lada Terra separating the relatively high lands of Lada Terra from the broad lowlands of Lavinia Planitia. The Lavinia Planitia basin is suspected to be an area of mantle downwelling, where there are less thermal stresses on the lithosphere. Because the nearby Lada Rise is speculated to be an area of mantle upwelling, models predict this could create a zone of weakness between these two convection cells which stretches the lithosphere, thus creating the rift zone. Associated with the rift zone are large lava flow fields and corona.
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These massive lava flows along with the suspected adjacent mantle upwelling slowly built and uplifted the Lada Rise some time after the initial formation of the Quetzalpetlatl Corona. This is indicated by the Quetzalpetlatl corona being offset with respect to the summit of the Lada Rise, or in other words, the corona is tilted at a different angle relative to the summit, implying the rock was tilted by the formation of the rise. Volcanism due to the formation of the Boala Corona (with its deposits cross cutting the previously mentioned structures) form the youngest lava flows observed and represents the latest episode of the evolution of the Lada Rise.
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Shiny Toy Guns, Vedera and the Upwelling each appeared on select dates. "The Wind Blows" was released as the album's second single on April 21 and was swiftly followed by the release of its music video on April 27, an alternative version was published the following October. On June 8, the album's opening track "I Wanna" was released as its third and final single, In June, the band performed a few shows in Europe with Sparks the Rescue. Two music videos (aimed at different music markets) for "I Wanna" were released: the first one premiered in mid-July, while the second was released on October 13, 2009.
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The strength of this subsidence inversion affects the strength of the marine layer, and how long it will take the clouds to dissipate. Additionally, the cool ocean water of the California Current, which flows out of the cold Gulf of Alaska, enhances the contrast between the cool air below the inversion layer and the warm air above it. A stronger inversion layer – one with a greater difference in temperature between the air above and the air below – often results in more and deeper marine layer clouds that persist longer into the day. Upwelling of colder-than-normal ocean water, associated with a La Niña, can strengthen this effect even more.
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During the climax of lithospheric rifting, as the crust is thinned, the Earth's surface subsides and the Moho becomes correspondingly raised. At the same time, the mantle lithosphere becomes thinned, causing a rise of the top of the asthenosphere. This brings high heat flow from the upwelling asthenosphere into the thinning lithosphere, heating the orogenic lithosphere for dehydration melting, typically causing extreme metamorphism at high thermal gradients of greater than 30 °C. The metamorphic products are high to ultrahigh temperature granulites and their associated migmatite and granites in collisional orogens, with possible emplacement of metamorphic core complexes in continental rift zones but oceanic core complexes in spreading ridges.
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The Summer Monsoon Current, located between 10 and 15 North latitude in the Arabian Sea, bends around India and Sri Lanka, and enters the Bay of Bengal. The Great Whirl is a gyre located around 10 N and 55 E, and is only present during the summer season. During the summer when the current flows toward the northeast, Ekman transport (to the right of the flow in the Northern Hemisphere) is offshore, transporting warmer waters deeper into the Arabian sea, and permitting upwelling of cooler waters along the coast. This sea surface temperature pattern (cooler waters west of warmer waters) reinforces the northward current through geostrophic flow.
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Satellite image of the Tibetan Plateau between the Himalayan mountains to the south and the Taklamakan Desert to the north In geology and physical geography, a plateau (, , or ; ; plural plateaus or plateaux), also called a high plain or a tableland, is an area of a highland consisting of flat terrain, that is raised sharply above the surrounding area on at least one side. Often one or more sides have deep hills. Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers. Plateaus are classified according to their surrounding environment as intermontane, piedmont, or continental.
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The terms summer, autumn, winter and spring do not generally apply. Lowlands around the equator generally have a tropical rainforest climate, also known as an equatorial climate, though cold ocean currents cause some regions to have tropical monsoon climates with a dry season in the middle of the year, and the Somali Current generated by the Asian monsoon due to continental heating via the high Tibetan Plateau causes Greater Somalia to have an arid climate despite its equatorial location. Average annual temperatures in equatorial lowlands are around during the afternoon and around sunrise. Rainfall is very high away from cold ocean current upwelling zones, from per year.
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The Coquimbo Region forms the narrowest part, or 'waist' of Chile, and is hence one of the country's more mountainous regions, as the Andes range runs closer to the sea than elsewhere. The region has notable marine species as well as taxa that are associated with the mountainous regions. With respect to marine organisms, the upwelling areas encourage bioproductivity off of this Pacific Coast area of Chile.R.N. Gibson, R.J.A. Atkinson and J.D.M. Gordon, 2007 In the southern mountainous areas of the Coquimbo Region, the rare and endangered Chilean Wine Palm is found, whose habitat is threatened by human overpopulation in the region and associated deforestation for residential expansion and agriculture.
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The Kaikōura Peninsula extends into the sea south of the town, and the resulting upwelling currents bring an abundance of marine life from the depths of the nearby Hikurangi Trench. The town owes its origin to this effect, since it developed as a centre for the whaling industry. The name Kaikōura means 'meal of crayfish' (kai – food/meal, kōura – crayfish) and the crayfish industry still plays a role in the economy of the region. However Kaikōura has now become a popular tourist destination, mainly for whale watching (the sperm whale watching is perhaps the best and most developed in the world) and swimming with or near dolphins.
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Zelenci Springs is considered the beginning of the longer of the two sources of the Sava, the longest Slovenian river at 221 km. The spring is actually the re-emergence of underground Nadiža Creek, whose first source is near the mountain lodge in the Tamar Valley, but which spends most of its course underground after disappearing at the Ledine gravel basin near Rateče. The porous chalk of the Zelenci Springs lake bed allows the constant upwelling of groundwater in the form of tiny jets, a phenomenon unique in Slovenia. The lake formed by the springs has a constant year-round temperature of 5 to 6 °C.
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This can occur when, for example, a warmer, less-dense air mass moves over a cooler, denser air mass. This type of inversion occurs in the vicinity of warm fronts, and also in areas of oceanic upwelling such as along the California coast in the United States. With sufficient humidity in the cooler layer, fog is typically present below the inversion cap. An inversion is also produced whenever radiation from the surface of the earth exceeds the amount of radiation received from the sun, which commonly occurs at night, or during the winter when the angle of the sun is very low in the sky.
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Oceanic primary production accounts for about half of the carbon fixation carried out on Earth. Approximately 50–60 Pg of carbon are fixed by marine phytoplankton each year despite the fact that they comprise less than 1% of the total photosynthetic biomass on Earth. The majority of this carbon fixation (~80%) is carried out in the open ocean while the remaining amount occurs in the very productive upwelling regions of the ocean. Despite these productive regions producing 2 to 3 times as much fixed carbon per area, the open ocean accounts for greater than 90% of the ocean area and therefore is the larger contributor.
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Fish are more abundant in the Later Stone Age but a wider range of species are present in the Middle Stone Age sequence. Chemical analysis of fish bone from the Later Stone Age and Middle Stone Age levels, using the carbon/nitrogen method, confirms the antiquity of the Middle Stone Age specimens. Most of the species present are not known to wash up after cold water upwelling events, hence scavenging of wash-ups was not the primary source of fish. No artefacts that appear to be obvious fishing equipment have been found, but the range and sizes of species present indicate that a number of methods must have been employed.
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Location of Anahim hotspot in millions of years ago, including the Anahim Volcanic Belt Nazko Cone probably began erupting about 340,000 years ago and has grown steadily since then. Like all of the Anahim volcanoes, Nazko Cone has its origins in the Anahim hotspot--a plume of magma rising from deep in the Earth's mantle. The hotspot remains in a fixed position, while the North American Plate drifts over it at a rate of 2 to 3.3 centimetres per year. The upwelling of the hot magma creates volcanoes, and each individual volcano erupts for a few million years before the movement of the plate carries it away from the rising magma.
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Though shellfish harvest closures are typically based on cells counts of Pseudo-nitzschia present, these cell counts do not always correlate with DA levels. Thus, it is important to understand the other environmental drivers that may lead to higher production of DA. The largest recorded DA event caused by Pseudo-nitzschia took place along the North American west coast in 2015, causing prolonged closures of razor clam, rock crab, and Dungeness crab fisheries. Later in 2015, DA was detected in whales, dolphins, porpoises, seals, and sea lions. This bloom was dominated by P. australis and likely caused by anomalous warm water and nutrients brought to the surface by upwelling conditions.
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Nutrient dynamics are also affected on a long-term scale by human and climate influences. Specifically, the Columbia River discharge rates, which govern bulk nutrient transport, follow Pacific Decadal Oscillation (PDO) and El Niño Southern Oscillation (ENSO). This is because of how these oscillations affect regional air temperature, precipitation patterns, and off shore wind, which in turn affect annual snowpack, sea surface temperatures, and upwelling and downwelling trends. Changes in these trends can alter the magnitude of runoff from land incorporated into the Columbia River system as well as coastal ocean inflow, which ultimately alter nutrient loading by either bringing in additional nutrients or washing them out.
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At 02:00 UTC on September 2, Dorian made landfall on Grand Bahama near the same intensity, with the same sustained wind speed. Afterward, Dorian's forward speed slowed to just , as the Bermuda High that was steering the storm westward weakened. Later that day, the storm began to undergo an eyewall replacement cycle to the north of Grand Bahama; the Bermuda High to the northeast of Dorian also collapsed, causing Dorian to stall just north of Grand Bahama. Around the same time, the combination of the eyewall replacement cycle and upwelling of cold water caused Dorian to begin weakening, with Dorian dropping to Category 4 status at 15:00 UTC.
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The marine effect: The in the atmosphere transfers to the ocean by dissolving in the surface water as carbonate and bicarbonate ions; at the same time the carbonate ions in the water are returning to the air as . This exchange process brings from the atmosphere into the surface waters of the ocean, but the thus introduced takes a long time to percolate through the entire volume of the ocean. The deepest parts of the ocean mix very slowly with the surface waters, and the mixing is uneven. The main mechanism that brings deep water to the surface is upwelling, which is more common in regions closer to the equator.
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These coastal eddies generate the upwelling of cold water from greater ocean depths where the rising cold water then mixes with the warmer water near the surface and subsequently lowers sea surface temperatures. Therefore, the Papagayo jet indirectly cools the coastal waters off the shores of Nicaragua and Costa Rica, extending the Costa Rica Dome. During the winter months, the coastal eddies and by extension the Papagayo jet, are thought to be the primary drivers of the dome. Model simulations indicate that without the Papagayo jet the Costa Rica Dome would not grow to such a large extent and may not even persist year-round.
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The medina is home to many small arts and crafts businesses, notably cabinet making and 'thuya' wood-carving (using roots of the Tetraclinis tree), both of which have been practised in Essaouira for centuries. The fishing harbour, suffering from the competition of Agadir and Safi remains rather small, although the catches (sardines, conger eels) are surprisingly abundant due to the coastal upwelling generated by the powerful trade winds and the Canaries Current. Essaouira remains one of the major fishing harbours of Morocco. Essaouira is also renowned for its kitesurfing and windsurfing, with the powerful trade wind blowing almost constantly onto the protected, almost waveless, bay.
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The Pliocene of Tuscany is representative of a nutrient-rich upwelling in coastal waters and the upper midnight zone along a continental slope. The Pliocene of Italy featured a wide array of marine mammals, for example dolphins such as Etruridelphis, the small sperm whale Kogia pusilla, beaked whales such as Tusciziphius, baleen whales such as Eschrichtioides, the dugong Metaxytherium subapenninum, and the monk seal Pliophoca. It also featured several sharks. The area has one of the most diverse Pliocene decapod crustacean assemblages, which indicates a sandy-muddy and at places hard-rock seafloor with calm, well-oxygenated, nearshore water, settings which are conducive to decapod life.
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Heating reduces the density of the lithosphere and elevates the lower crust and lithosphere. In addition, mantle plumes may heat the lithosphere and cause prodigious igneous activity. Once a mid-oceanic ridge forms and seafloor spreading begins, the original site of rifting is separated into conjugate passive margins (for example, the eastern US and NW African margins were parts of the same rift in early Mesozoic time and are now conjugate margins) and migrates away from the zone of mantle upwelling and heating and cooling begins. The mantle lithosphere below the thinned and faulted continental oceanic transition cools, thickens, increases in density and thus begins to subside.
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The steering flow hence diminished, causing Dorian to decelerate. Creeping slowly westwards, Dorian weakened slightly before making landfall near South Riding Point, Grand Bahama with winds of 180 mph (285 km/h) at 02:15 UTC on September 2\. The system moved off the north coast of Grand Bahama six hours later still as a Category 5 hurricane, albeit with a larger eye and lower winds because of land interaction and upwelling of cooler waters beneath the system. These factors, coupled with Dorian's slow motion, caused steady weakening over the next couple of days, with Dorian dropping to Category 3 status at 06:00 UTC September 3\.
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The winds blow at speeds of 80 km/h or more down the hillsides from Chivela Pass and over the waters of the Gulf of Tehuantepec, sometimes extending more than 500 miles (800 km) into the Pacific Ocean. The surface waters under the Gulf of Tehuantepec wind jet can cool by as much as 10 °C in a day. In addition to the cold water that is detectable from other satellite sensors, the ocean's response to these winds shows up in satellite estimates of chlorophyll from ocean color measurements. The cold water and high chlorophyll concentration are signatures of mixing and upwelling of cold, nutrient-rich deep water.
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The ultimate fate of crustal material is key to understanding geochemical cycling, as well as persistent heterogeneities in the mantle, upwelling and myriad effects on magma composition, melting, plate tectonics, mantle dynamics and heat flow. If slabs are stalled out at the 660-km boundary, as the layered- mantle hypothesis suggests, they cannot be incorporated into hot spot plumes, thought to originate at the core-mantle boundary. If slabs end up in a "slab graveyard" at the core-mantle boundary, they cannot be involved in flat slab subduction geometry. Mantle dynamics is likely a mix of the two end-member hypotheses, resulting in a partially layered mantle convection system.
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Along the California coast, the prevailing current flows from the northwest and is cool owing to its origin in the North Pacific. Additional cooling occurs due to strong upwelling of cooler subsurface waters, especially along the immediate coastline and near various promontories.Climate of San Francisco, NOAA Technical Memorandum NWS WR·126, Jan Null, National Weather Service Forecast Office, San Francisco Bay Area, California, January, 1995 Sea surface temperatures along the coast are generally year-round. When the marine layer encounters the colder waters along the California coast, it cools to its dewpoint, and if small particles called condensation nuclei are present, liquid water drops will form.
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Basin and Range extension is therefore thought to be unrelated to the kind of extension produced by mantle upwelling which may cause narrow rift zones, such as the Afar Triple Junction. Geologic processes that elevate heat flow are varied, however some researchers suggest that heat generated at a subduction zone is transferred to the overriding plate as subduction proceeds. Fluids along fault zones then transfer heat vertically through the crust. This model has led to increasing interest in geothermal systems in the Basin and Range, and requires consideration of the continued influence of the fully subducted Farallon plate in the extension responsible for the Basin and Range Province.
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Several rocks lie off the island, including a group of four 9 to 12 m (30 to 40 ft) high rocks about 800 m (about 0.5 mi) to the north-northwest and several detached rocks 160 to 320 m (0.1 to 0.2 mi) to the south. The island is often enveloped in dense fog due to cold bottom water upwelling to the surface. The flood tidal current off the island sets west, while the ebb sets to the east or east-southeast. These currents may reach up to 1.5 to 2 knots during spring tides and create numerous eddies, small whirlpools, and tide rips around the island for some distance offshore.
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While maintaining peak intensity, Fantala's forward movement slowed, as the ridge to its south over Madagascar weakened. The cyclone turned back to the southeast due to the building influence of a ridge to the northeast, and the storm retraced its former path. Cooler waters along its path - the result of upwelling - as well as another eyewall replacement cycle, caused Fantala to weaken to an intense tropical cyclone by 19 April. Fantala had maintained at least Category 4-equivalent intensity for about 90 hours, and of those 90 hours, Fantala spent about 30 hours at both very intense tropical cyclone status and Category 5-equivalent intensity.
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Salinity is another important water quality issue. Drainage return flows to the Nile result in an increase in salinity of the water from 250 ppm (mg/l) at Aswan to 2,700 ppm at the Delta barrages.Egyptian Drainage Research Institute, yearbook 1995/1996 However, more salts are being discharged into the Mediterranean Sea than are entering at Aswan (see Irrigation for agriculture in Egypt) so that in the long run the salinity of the water at the Delta barrages could decrease. However, saline groundwater of marine origin enters the Delta through pumping of brackish water and upwelling in lakes and drains, thus counterbalancing this effect.
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Fig. 3 Illustration of Langmuir rotations; open circles=positively buoyant particles, closed circles=negatively buoyant particles In exposed systems, wind can create turbulent, spiral-formed surface currents called Langmuir circulations (Fig. 3). Exactly how these currents become established is still not well understood, but it is evident that it involves some interaction between horizontal surface currents and surface gravity waves. The visible result of these rotations, which can be seen in any lake, are the surface foamlines that run parallel to the wind direction. Positively buoyant particles and small organisms concentrate in the foamline at the surface and negatively buoyant objects are found in the upwelling current between the two rotations.
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The "Blue Hole" a small and at times "ultra blue" upwelling of natural water from which nearly 90% of the Paulinskill Stream comes from. The Paulinskill Stream, so named for Queen Paulina of Germany by early pioneers flows Southwest and empties into the Delaware River above Belidiere N.J. The upswelling of source water a result of the Limestone base rock that underlies this entire Region. To the East is Lake Mohawk where the Wallkill River flows out of- heading North to its joining with the Hudson River. This local region is therefore some of the source water for two great watersheds – one working its way South, the other North, both starting from this single formation.
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Driven by this sinking and the upwelling that occurs in lower latitudes, as well as the driving force of the winds on surface water, the ocean currents act to circulate water throughout the entire sea. When global warming is added into the equation, changes occur, especially in the regions where deep water is formed. With the warming of the oceans and subsequent melting of glaciers and the polar ice caps, more and more fresh water is released into the high latitude regions where deep water is formed. This extra water that gets thrown into the chemical mix dilutes the contents of the water arriving from lower latitudes, reducing the density of the surface water.
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Doron Nof is an American academic scientist who has published on various aspects of physical oceanography, including flows through straits and passages, boundary current dynamics, upwelling in coastal regions, the dynamics of eddies in the upper and deep ocean, equatorial dynamics, general circulation problems, and cross-equatorial flows. He is the Distinguished Nansen Professor of Physical Oceanography at Florida State University. He is a recipient of the Fridtjof Nansen Medal awarded by the European Geosciences Union. In addition to his scientific research, he has received notoriety in the popular press for using physical oceanography to explain Biblical and other historical phenemona, such as the parting of the Red Sea and walking on water.
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Southern right whale dolphins have a circumpolar distribution across the Southern Hemisphere, generally occurring in cool temperate to Sub- Antarctic waters between 30°S and 65°S. The precise boundary of their range has not been estimated or closely studied but the southern limit of the species appears to be bounded by the Antarctic Convergence while the northern limit seems bounded by the Tropical Convergence although rare sightings beyond these limits have been recorded. Most sightings of the southern right whale dolphins occur in offshore and deep waters, with temperatures ranging between 1 and 20 °C. In regions where deep waters approach the coast and in upwelling areas, they have occasionally been observed near shore.
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There are many complex interactions with the warm-core ring and thus lifetime productivity is not very different from the surrounding shelf water. A study in 1998 found that the primary productivity within a warm-core ring was almost the same as in the cold jet outside it, with evidence of upwelling of nutrients within the ring. In addition, there was discovery of dense populations of phytoplankton at the nutricline in a ring, presumably supported by upward mixing of nutrients. Furthermore, there have been acoustic studies in the warm-core ring, which showed intense sound scattering from zooplankton and fish populations in the ring and very sparse acoustic signals outside of it.
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Winston east of Queensland, with subtropical characteristics on 27 February Still under favorable conditions, Winston maintained intensity until early on 21 February, when upwelling of cooler waters beneath the decelerating cyclone caused it to weaken into a Category 4 cyclone. On 22 February, Winston sharply recurved south-southeastwards as the primary steering mechanism shifted from a ridge retrograding westwards to a ridge building to the east; moreover, dry air hindered reintensification. Very strong vertical wind shear and cooling sea surface temperatures resulted in steady weakening, and WInston dropped below severe tropical cyclone intensity on 23 February. Later, the low-level circulation center became fully exposed with shallow convection sheared to the south.
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Aurora Subglacial Basin is a large subglacial basin of Wilkes Land to the west of Dome Charlie and trending northwest toward the coast in the vicinity of Shackleton Ice Shelf. The basin was delineated by the SPRI-NSF-TUD airborne radio echo sounding program, 1967-79, and named after Aurora, the ship of the Australasian Antarctic Expedition, 1911-14, led by Douglas Mawson. The Aurora Subglacial Basin is largely grounded below sea level, making it susceptible to marine ice sheet instability. The Aurora Subglacial Basin is drained in part by Totten Glacier, which responds readily to melt induced by upwelling of warm circumpolar deep water and could raise global sea level by more than 3.5 m.
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Despite its current status as one of the driving forces of plate tectonics, ridge push was not included in any of Alfred Wegener's 1912-1930 proposals of continental drift, which were produced before the discovery of mid-ocean ridges and lacked any concrete mechanisms by which the process might have occurred. Even after the development of acoustic depth sounding and the discovery of global mid-ocean ridges in the 1930s, the idea of a spreading force acting at the ridges was not mentioned in scientific literature until Harry Hess's proposal of seafloor spreading in 1960, which included a pushing force at mid-ocean ridges as a result of upwelling magma wedging the lithosphere apart.
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Among those, the six main species that usually form the intermediate trophic layer represent over half of the catch. During an El Niño, wind indirectly drives warm water to the South American coast, reducing the effects of cold upwelling Besides directly causing the collapse of the ecosystem due to their absence, this can create problems in the ecosystem through a variety of other methods as well. The animals higher in the trophic levels may not completely starve to death and die off, but the decreased food supply could still hurt the populations. If animals do not get enough food, it will decrease their reproductive viability meaning that they will not breed as often or as successfully as usual.
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Northwesterly shear caused by an upper-level low caused the system to have a sheared appearance, but it continued to strengthen as it gradually moved north-northwestward. Sally began to go through a period of rapid intensification around midday on September 14\. Its center reformed under a large burst of deep convection and it strengthened from a 65 mph (105 km/h) tropical storm to a 90 mph (140 km/h) Category 1 hurricane in just one and a half hours. It continued to gain strength and became a Category 2 hurricane later that evening. However, upwelling due to its slow movement as well increasing wind shear weakened Sally back down to Category 1 strength early the next day.
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Soon after, Jimena turned to the west-northwest and underwent an eyewall replacement cycle. Despite weakening slightly, Jimena remained at Category 4 status, thus becoming one of three simultaneous Category 4 Pacific hurricanes east of the International Date Line on August 30—the first such occurrence of its kind. On August 30, Jimena completed the eyewall replacement cycle and quickly regained 150 mph (240 km/h) winds, this time with a larger eye of 40–45 mi (65–75 km) diameter. However, upwelling of cooler waters beneath the hurricane and entrainment of mid-level dry air into the circulation, as well as a second eyewall replacement cycle, resulted in a steady weakening beginning late on August 31\.
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The occurrence of hypoxia in open coast upwelling systems reflects ocean conditions that control the delivery of O2-deficient and nutrient-rich deep water onto continental shelves. The mid-shelf location in the sheltered region of the Heceta Bank complex is especially vulnerable to O2-deficient events due to the large shelf width, as well as weak currents and high productivity. During a 2002 July survey, Oregon Department of Fish and Wildlife found only dead fish and invertebrates in the normally productive fish habitat at Heceta Bank. The hypoxic, or O2-deficient, zone that covered more than 700 km2 between Newport and Heceta Head was believed to be the cause of the fish and invertebrate mortality.
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Duffy next moved to the University of Cape Town where he ran the seabird component of the Benguela Ecology Project, again producing research on seabirds and their interactions with fisheries. Concurrently, he and his colleagues began research in the Chilean sector of the Humboldt Current. Duffy began simple models of upwelling trophic relations that were to predate many non-linear models for marine ecosystems. In 1986, Duffy and his family moved to Costa Rica where he created the Centro de Documentacion en Vida Silvestre (Biodoc) in Heredia, Costa Rica as part of a United States Fish and Wildlife Service sponsored wildlife management graduate program in which Duffy was one of the first professors.
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This stems from a discontinuity in the acoustic impedance of water created by the sudden change in density. In scuba diving, a thermocline where water drops in temperature by a few degrees Celsius quite suddenly can sometimes be observed between two bodies of water, for example where colder upwelling water runs into a surface layer of warmer water. It gives the water an appearance of wrinkled glass, the kind often used in bathroom windows to obscure the view, and is caused by the altered refractive index of the cold or warm water column. These same schlieren can be observed when hot air rises off the tarmac at airports or desert roads and is the cause of mirages.
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Present-day activity occurs at the top of the Monowai cone, and manifests itself in the form of earthquakes, discoloured water, emission of gases and pumice rafts, rumbling sounds and upwelling water. Underwater, this activity generates cones, debris flows, lava flows and pyroclastic flows as well as sector collapses and lava dome growth, which has caused the summit of Monowai cone to shift southward. Several seismic swarms have been observed on Monowai, including a strong swarm in May 2002 that may be associated with a sector collapse, and sound waves from the volcano have been recorded as far aways as Ascension Island in the Atlantic Ocean. Monowai volcano is a fast-growing edifice, with growth rates ranging between .
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Flipped car and flooding on a street in Muscat, Oman The Muscat International Airport reopened after three days while Fujairah reopened on June 7 after it was closed the day before. The cyclone caused little impact to oil facilities along its path; after the initial price rises, oil dropped over US$2 per barrel as a result. Across the northern Arabian Sea, the passage of Gonu produced stronger winds and significant upwelling – an oceanographic phenomenon that involves the replacement of the nutrient-depleted surface water with deeper nutrient-rich water; the passage caused a significant increase in phytoplankton. Additionally, the cyclone delayed the arrival of the Indian Ocean south-west monsoon in the Western Ghats in India.
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Such emergence and drowning has been recorded at carbonate platforms of that age around the world and may be the consequence of tectonic events across the Pacific Ocean, culminating in the uplift of a part thereof. At that time, a last phase of volcanic activity on Allison Guyot generated several cones on its eastern part. The evidence for this theory is not conclusive, and another theory holds that the drowning of Allison Guyot occurred when it moved through equatorial waters, where upwelling increased the amount of nutrients available, hampering the growth of platforms. The waters might also have been too hot to support the survival of reef builders, as happens in present-day coral bleaching events.
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He was elected a Fellow of the Royal Society of London in 1986. His candidacy citation read: "Dr A.E. Gill is internationally recognised for his work in geophysical fluid dynamics and leads a small but highly productive team working on problems in dynamical oceanography and meteorology. He has made outstanding theoretical contributions to a wide range of topics, including the stability of pipe flow, thermal convection, circulation of the Southern Ocean, seasonal variability of the ocean, waves in rotating fluids, wind-induced upwelling, coastal currents and sea-level changes and coastally-trapped waves in the atmosphere, and he is particularly effective in the way he is able to interpret observations and guide the activities of observational workers".
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GFNMS has administrative jurisdiction over the northern portion of the Monterey Bay National Marine Sanctuary, from the San Mateo/Santa Cruz County line northward to the existing boundary between the two sanctuaries. GFNMS maintains an administrative office and public Visitor Center on Crissy Field in the Presidio of San Francisco. GFNMS is located within the California Current ecosystem, one of four major eastern boundary currents in the world, that stretches along the western coast of North America from southern Canada to northern Mexico. Due to a high degree of wind-driven upwelling, there is a ready supply of nutrients to surface waters and the California Current ecosystem is one of the most biologically productive regions in the world.
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Location of Anahim hotspot in millions of years ago, including the Anahim Volcanic Belt The Ilgachuz Range began erupting 6.1 million years ago and has grown steadily since then. Like all of the Anahim volcanoes, the Ilgachuz Range has its origins in the Anahim hotspot--a plume of magma rising from the Earth's mantle in central British Columbia. The hotspot remains in a fixed position, while the North American Plate drifts over it at a rate of 2 to 3.3 centimetres per year. The upwelling of the hot magma creates volcanoes, and each individual volcano erupts for a few million years before the movement of the plate carries it away from the rising magma.
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The presence of hot asthenospheric mantle at shallow levels beneath the western margin of North America is likely to generate melt and cause magmatism. Accordingly, a sequence of volcanoes in the wake of the MTJ passing were activated; this magmatism likely leads to the intrusion of plutons within the overlying crust in the region. An example of volcanic bodies that formed by magma upwelling and solidification are the Nine Sisters, located between Morro Bay and San Luis Obispo in California. The source of the material which flows into the slab window is a matter of debate, specifically whether it is derived directly from the underlying mantle, or from the mantle wedge to the east.
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Bloom of E. huxleyi in Hardangerfjord, NorwayMay 2020 Emiliania huxleyi is a species of coccolithophore found in almost all ocean ecosystems from the equator to sub-polar regions, and from nutrient rich upwelling zones to nutrient poor oligotrophic waters.Charalampopoulou, Anastasia (2011) Coccolithophores in high latitude and Polar regions: Relationships between community composition, calcification and environmental factors University of Southampton, School of Ocean and Earth Science, Doctoral Thesis, 139pp. It is one of thousands of different photosynthetic plankton that freely drift in the euphotic zone of the ocean, forming the basis of virtually all marine food webs. It is studied for the extensive blooms it forms in nutrient-depleted waters after the reformation of the summer thermocline.
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Eddies of the Agulhas Current meanders past the Agulhas Bank leaking warm and salty water into the South Atlantic before retroflecting back into the Indian Ocean Mean chlorophyl-a concentration map of the oceans surrounding Southern Africa for 2009. Note the high productivity water in the Agulhas Retroflection and the very high concentrations along the west coast, due to the upwelling of mineral rich water from the cold depths the South Atlantic Ocean, forming the Benguela Current. Benguela Current in the South Atlantic Gyre The Agulhas Current is the western boundary current of the southwest Indan Ocean. It flows south along the African east coast and along the south-eastern edge of the bank.
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Evidence is showing that the East African Rift System is a classic continental-continental rifting event but the extent of research due to its age and continuing formation is diverse and filled with many hypothetical models that support and contrast each other. The rifting began in the Paleogene due to the far-field stress from the subduction of the Arabian plate under the Eurasian plate and the mantle upwelling that has been seen to move over time because of the multiple area of hot spots around the EARS. This crustal uplift has created extension and horst and grabens and even listric faults which indicate a pre- oceanic basin structure. The future of this area is unknown.
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Along with the decrease of atmospheric carbon dioxide reducing the global temperature, orbital factors in ice creation can be seen with 100,000-year and 400,000-year fluctuations in benthic oxygen isotope records. Another major contribution to the expansion of the ice sheet was the creation of the Antarctic Circumpolar Current. The creation of the Antarctic circumpolar current would isolate the cold water around the Antarctic, which would reduce heat transport to the Antarctic along with creating ocean gyres that result in the upwelling of colder bottom waters. The issue with this hypothesis of the consideration of this being a factor for the Eocene-Oligocene transition is the timing of the creation of the circulation is uncertain.
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According to this hypothesis, groundwater with dissolved minerals came to the surface, in and around craters, and helped to form layers by adding minerals —especially sulfate— and cementing sediments... In other words, some layers may have been formed by groundwater rising up depositing minerals and cementing existing, loose, aeolian sediments. The hardened layers are consequently more protected from erosion. A study published in 2011 using data from the Mars Reconnaissance Orbiter, show that the same kinds of sediments exist in a large area that includes Arabia Terra. It has been argued that areas that are rich in sedimentary rocks are also those areas that most likely experienced groundwater upwelling on a regional scale.
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The increasing eastward momentum imparted by the winds causes water parcels to drift outward from the axis of the Earth's rotation (in other words, northward) as a result of the Coriolis force. This northward Ekman transport is balanced by a southward, pressure-driven flow below the depths of the major ridge systems. Some theories connect these flows directly, implying that there is significant upwelling of dense deep waters within the Southern Ocean, transformation of these waters into light surface waters, and a transformation of waters in the opposite direction to the north. Such theories link the magnitude of the Circumpolar Current with the global thermohaline circulation, particularly the properties of the North Atlantic.
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This technique was only executed by M1 and M5. These new techniques are thought to have been developed by these whales to help them herd small schooling fish (likely capelin) in the well-mixed waters of the Saguenay Fjord; these tactics were not observed in the nearby Laurentian Channel Head, where "strong tidal currents, a stratified water column and bottom topography combine to create large areas of upwelling in which prey are forced to the surface". In July 2007, a minke whale with what appeared to be a rope injury was observed surface feeding on capelin in the Gulf of St. Lawrence. The long, linear laceration extended around the ventral pleats, restricting their distention.
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From there it is retroflexed (turned sharply round) in an easterly direction by the South Atlantic, South Indian and Southern Ocean currents, known as the "West Wind Drift", which flow eastwards round Antarctica. The Benguela Current, on the other hand, is an upwelling current which brings cold, mineral-rich water from the depths of the Atlantic Ocean to the surface along the west coast of Southern Africa. Having reached the surface it flows northwards as a result of the prevailing wind and Coriolis forces. The Benguela Current, therefore, effectively starts at Cape Point, and flows northwards from there,Tyson, P.D., Preston-Whyte, R.A. (2000) The Weather and Climate of Southern Africa. pp. 221-223.
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Hurst Spit is a hook-shaped shingle spit which extends for from the Hampshire shore into the Solent towards the Isle of Wight. The spit forms a barrier which shelters a Site of Special Scientific Interest known as Hurst Castle And Lymington River Estuary. To reach the end of the spit one can either catch the seasonal ferry from Keyhaven, or follow the footpath (part of the Solent Way) along the top of the spit. The sea route past Hurst Spit can be hazardous to boats because the constriction to the tidal flow caused by the spit creates strong tidal streams, as well as spiky waves mixed with circular areas of flat sea caused by the upwelling water.
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Galileo Regio is a large, dark surface feature on Jupiter's moon Ganymede. It is a region of ancient dark material that has been broken apart by tectonism and is now surrounded by younger, brighter material (such as that of Uruk Sulcus) that has been upwelling from Ganymede's interior. It is thought to be some 4 billion years old and is heavily cratered and palimpsested, but also has a unique distribution of furrows and smooth terrain that has been the subject of conflicting speculation regarding cause or origin. The distribution of smooth terrain on Galileo Regio suggests that the ancient crust of Ganymede was relatively thin in the equatorial region and thickened poleward in this area.
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If not split into several species, Audubon's shearwater ranges across the Indian Ocean north to the Arabian Sea, throughout the north-west and central Pacific, in the Caribbean, and parts of the eastern Atlantic. It is a species of tropical waters; only some Atlantic populations and Bannerman's shearwater of the Ogasawara Islands occur farther north. Unlike the larger shearwaters, adult Audubon's shearwaters are not thought to wander much or undertake great migrations, although their young birds do so before breeding, and western Indian Ocean birds may gather in large numbers at the upwelling zone in the Arabian Sea. It is adaptable as regards its preferred marine habitat; it can be found in pelagic, offshore and inshore waters.
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The cost of deep drilling is thirty times greater than that of a conventional well, constituting up to $200,000 to equipe a well at 300 meters (compared to just $6,000 for a conventional well). A 2017 publication by the Schiller Institute, "Extending the New Silk road to West Asia and Africa", states that "WATEX and other modern theories of hydrology prove the criticism that fossil water and completely confined aquifers is a myth". The report points out that "while a great deal of water is stored for thousands of years in some underground aquifers, a great amount of water is continuously recharging aquifers through very deep fracture systems, upwelling from great depths...".
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It is believed to be drowned by rapid sea level rise caused by deglaciation and subsidence of the platform, which enabled coralline algal- foraminiferal nodules and halimeda limestones to cover the coral reefs. Plate movements carrying carbonate platforms to latitudes unfavourable for carbonate production are also suggested to be one of the possible reasons for drowning. For example, guyots located in the Pacific Basin between Hawaiian and Mariana Islands are believed to be transported to low southern latitudes (0-10°S) where equatorial upwelling occurred. High amounts of nutrients and higher productivity caused decrease in water transparency and increase in bio-eroders populations, which reduced carbonate accumulation and eventually led to drowning.
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Although extensive rifting has not yet been recognized in the Northern Cordilleran Volcanic Province, volcanism throughout the past 1.6 million years is possibly due to repetitive upper mantle upwelling and adjacent transtension throughout the Queen Charlotte Fault, accommodated partly by numerous east-west trending fault zones that extend all through the Northern Cordilleran Volcanic Province. The volcanics comprising the Northern Cordilleran Volcanic Province are consistent with the rifting environment. Alkaline basalt, lesser hawaiite and basanite magmas from effusive eruptions create the massive shield volcanoes and small cinder cones throughout the volcanic province, several of which comprise lherzolite magma. Felsic magmas from more viscous eruptions create the massive central volcanoes and largely consist of trachyte, pantellerite and comendite lavas.
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The African large low-shear-velocity province (superplume) The mantle plume hypothesis proposes that areas of volcanism not readily explained by plate tectonics, called hotspots, are a result of thermal upwelling from as deep as the core- mantle boundary that become diapirs in the crust. This is an actively contested theory, although tomographic images suggest there are anomalies beneath some hotspots. The best imaged of these are large low-shear-velocity provinces, or superplumes, visible on S-wave models of the lower mantle and believed to reflect both thermal and compositional differences. The Yellowstone hotspot is responsible for volcanism at the Yellowstone Caldera and a series of extinct calderas along the Snake River Plain.
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In contrast, San Francisco has cool summers with daily highs around due to the continuous upwelling of cold subsurface waters along the coast. Because most regions with a Mediterranean climate are near large bodies of water, temperatures are generally moderate, with a comparatively small range of temperatures between the winter low and summer high (although the daily range of temperature during the summer is large due to dry and clear conditions, except along the immediate coasts). Temperatures during winter only occasionally fall below the freezing point and snow is generally seldom seen. In the summer, the temperatures range from mild to very hot, depending on distance from a large body of water, elevation, and latitude.
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This rifting created a divergent plate margin that would play an integral role of the future geologic processes to follow. Rifting, which involves the stretching of pre-existing crust and mantle lithosphere, was initiated by the existence of sufficient horizontal deviatoric tensional stress that broke the lithosphere. Eventually rifting gave way to sea floor spreading in the Atlantic and Gulf of Mexico in the mid Jurassic, around ≈165 Ma. Sea floor spreading is where new oceanic lithosphere is being created by upwelling of material, unlike rifting where it only involved the stretching of the crust. Convection currents in the sub-lithospheric mantle are the driving mechanisms that caused sea floor spreading to occur.
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Early summers can often bring cool, overcast weather (fog and low stratus clouds) to coastal California. As such, the warmest summer weather is delayed until August, even September in many areas of the California coast; on average, September is the warmest month in San Francisco, CA. Upwelling of cold Pacific waters also contributes to the frequent cool spring and early summer weather in coastal California. In California's inland river valleys (Bakersfield, Sacramento areas), the wet-winter, dry-summer pattern remains, but winters are cooler and more prone to occasional frost or freeze, while summers are much hotter, with blazing sunshine and daytime high temperatures not uncommonly in the 90s °F to over 100 °F (38 °C).
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Jelly-falls are primarily made up of the decaying corpses of Cnidaria and Thaliacea (Pyrosomida, Doliolida, and Salpida). Several circumstances can trigger the death of gelatinous organisms which would cause them to sink. These include high levels of primary production that can clog the feeding apparatuses of the organisms, a sudden temperature change, when an old bloom runs out of food, when predators damage the bodies of the jellies, and parasitism. In general, however, jelly-falls are linked to jelly-blooms and primary production, with over 75% of the jelly falls in subpolar and temperate regions occurring after spring blooms, and over 25% of the jelly- falls in the tropics occurring after upwelling events.
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The courses of the warm Agulhas current (red) along the east coast of South Africa, and the cold Benguela current (blue) along the west coast. Note that the Benguela current does not originate from Antarctic waters in the South Atlantic Ocean, but from upwelling of water from the cold depths of the Atlantic Ocean against the west coast of the continent. The two currents do not "meet" anywhere along the south coast of Africa, except as random eddies from the two currents, that arise and intermingle west of Cape Agulhas. Cape Point is situated within the Table Mountain National Park, within a section of the park referred to as Cape of Good Hope.
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When New Horizons first sent back data from Pluto, Pluto was thought to be losing hundreds of tons of its atmosphere an hour to ultraviolet light from the Sun; such an escape rate would be too great to be resupplied by comet impacts. Instead, nitrogen was thought to be resupplied either by cryovolcanism or by geysers bringing it to the surface. Images of structures that imply upwelling of material from within Pluto, and streaks possibly left by geysers, support this view. Subsequent discoveries suggest that Pluto's atmospheric escape was overestimated by several thousand times and thus Pluto could theoretically keep its atmosphere without geological assistance, though evidence of ongoing geology remains strong.
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For such an increase to occur would have required an accelerated influx of land-derived nutrients coupled with vigorous upwelling, requiring major climate change on a global scale. Geochemical data from oxygen-isotope ratios in carbonate sediments and fossils, and magnesium/calcium ratios in fossils, indicate that all major oceanic anoxic events were associated with thermal maxima, making it likely that global weathering rates, and nutrient flux to the oceans, were increased during these intervals. Indeed, the reduced solubility of oxygen would lead to phosphate release, further nourishing the ocean and fuelling high productivity, hence a high oxygen demand – sustaining the event through a positive feedback. Here is another way of looking at oceanic anoxic events.
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The temperature of the upper convecting mantle is different from one side of the planet to the other with lateral temperature differences for downwellings up to several hundred kelvins. However, the temperature of the upwelling is unaffected by downwelling and surface temperature variations. On the permanent dayside of the tidally locked planet where the surface temperature is hot from continuously facing its sun, the surface takes part in convection, which is the evidence that all the surface of this hemisphere being covered in oceans of lava. On the permanent nightside, the surface is cool enough for the formation of the crust with pools of lava above the convective mantle with intense volcanism.
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In geology, the slab gap hypothesis is one of the explanations put forward to explain several instances of crustal extension that occur inland near former subduction zones. Standard plate tectonic theory holds that once a trench is closed by an overriding plate reaching a rift/spreading center, the plate that has just been fully consumed continues to descend beneath the overriding plate for some time, transmitting compressive pressures to the overriding plate above as well as occasional volcanism. Meanwhile, the descending plate leaves behind it a "window" of inactivity. In this view, there is no mantle upwelling, so once the crustal rift is overridden, the only residual effects are from the remnant descending plate slab.
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As volcanism moves along the Hawaiian chain, the Hawaiian Arch moves behind the volcanism at a distance of several hundred kilometres, and appears to have passed under Oahu in geologically recent times. The tectonic effect of the Hawaiian Arch passing under the island may be responsible for the onset of Honolulu Volcanics volcanism, as well as of the Koloa Volcanics on Kauai and perhaps for future volcanism on Maui or Molokai, but also for ongoing uplift on Oahu. Other proposed mechanisms are a conductive heating of the lithosphere or ongoing upwelling in the mantle plume. The terrain that the volcanoes developed on includes both old volcanic rocks of the Koʻolau volcano, sediments of the coastal plains, and soils.
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The cold deep sea water (<10°C) is pumped to the sea surface area to suppress the sea surface temperature (>26°C) by artificial means using electricity produced by mega scale floating wind turbine plants on the deep sea. The lower sea water surface temperature would enhance the local ambient pressure so that atmospheric landward winds are created. For upwelling the cold sea water, a stationary hydraulically driven propeller (≈50 m diameter similar to a nuclear powered submarine propeller) is located on the deep sea floor at 500 to 1000 m depth with a flexible draft tube extending up to the sea surface. The draft tube is anchored to the sea bed at its bottom side and top side to floating pontoons at the sea surface.
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As the solar cycle progresses towards its maximum, sunspots tend to form closer to the solar equator, following Spörer's law. The 11-year sunspot cycle is half of a 22-year Babcock–Leighton solar dynamo cycle, which corresponds to an oscillatory exchange of energy between toroidal and poloidal solar magnetic fields. At solar-cycle maximum, the external poloidal dipolar magnetic field is near its dynamo-cycle minimum strength, but an internal toroidal quadrupolar field, generated through differential rotation within the tachocline, is near its maximum strength. At this point in the dynamo cycle, buoyant upwelling within the convection zone forces emergence of the toroidal magnetic field through the photosphere, giving rise to pairs of sunspots, roughly aligned east–west with opposite magnetic polarities.
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Dry winter days also tend to provide excellent weather at Ocean Beach (especially in drought years). The water at Ocean Beach is noteworthy for its strong, dangerous currents and powerful waves, which make it popular among serious surfers. The water is cold, due in part to a process known as upwelling, in which frigid water from below the ocean surface rises to replace the surface water that moves away from the beach as a result of the Coriolis effect. The rapid rip currents, cold water, and threat of sneaker waves make the ocean dangerous for casual swimmers and even those who simply want to set foot in it, especially those with no wetsuits and no lifejackets, because swimmers have been swept away and drowned.
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The oxidation of hydrogen sulfide has been considered one of the most important processes in the environment, given that the oceans have had very low oxygen and high sulfidic conditions over most of the Earth's history. The modern analog ecosystems are deep marine basins such as those in the Black Sea, near the Cariaco trench and the Santa Barbara basin. Other zones of the ocean that experience periodic anoxic and sulfidic conditions are the upwelling zones off the coasts of Chile and Namibia, and hydrothermal vents, which are a key source of H2S to the ocean. Sulfur oxidizing microorganisms (SOM) are thus restricted to upper sediment layers in these environments, where oxygen and nitrate, which are electron acceptors with high redox potentials are available.
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This can lead to a decreasing population, especially in species that do not breed often under normal circumstances or become reproductively mature late in life. Another problem is that the decrease in the population of a species due to fisheries can lead to a decrease in genetic diversity, resulting in a decrease in bio-diversity of a species. If the species diversity is decreased significantly, this could cause problems for the species in an environment that is so variable and quick- changing; they may not be able to adapt, which could result in a collapse of the population or ecosystem. Another threat to the productivity and ecosystems of upwelling regions is El Niño-Southern Oscillation (ENSO) system, or more specifically El Niño events.
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This spillway utilized two 60-inch steel tubes to direct the water under the powerhouse. In addition, the dam has one small concrete spillway with a single tainter gate.. Consumers Energy, who owns and operates the Mio Dam, installed a cool water upwelling system in 2009 to reduce river water temperatures on hot days as negotiated with a comprehensive settlement agreement with multiple resource agencies to improve habitat for fish and other aquatic life downstream. Studies showed that some fish species, like Trout, became stressed as water temperatures increased. The current system in place at Mio and other Consumers Energy Dams uses an underwater air bubbler to lift/mix colder lower-lying water to the intake pipes for the turbines.
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The bank's main fisheries are: (a) demersal trawl fishery for some species of flatfish, rockfish, and sablefish; (b) midwater trawl fishery for rockfish and Pacific hake; (c) longline fishery for rockfish, sablefish, and Pacific halibut; (4) vertical longline fishery for rockfish; and (e) salmon fishery mainly during upwelling events. Some of these stocks have undergone declines in biomass during the 1980s and 1990s, which were produced by variations in the productivity of the California Current as well as high harvest levels. In particular, some rockfish species showed a higher decline in the 1990s due to life-history characteristics that make them more vulnerable to overfishing. By 2002, seven species of U.S. west coast rockfish, as well as lingcod and Pacific hake or whiting were declared officially overfished.
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The Giant Staircase between Yosemite and Little Yosemite Valley When the North American Plate on its slow journey westwards encountered the Pacific Plate approximately 250 million years ago during the Paleozoic, the latter began to subduct under the North American continent. Intense pressure underground caused some of the Pacific Plate to melt, and the resulting upwelling magma pushed up and hardened into the granite batholith that makes up much of the Sierra Nevada. Extensive layers of marine sedimentary rock that originally made up the ancient Pacific seabed were also pushed up by the rising granite, and the ancestral Merced River formed on this layer of rock. Over millions of years, the Merced cut a deep canyon through the softer sedimentary rock, eventually hitting the hard granite beneath.
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It is due to a summer-to-winter circulation giving rise to upwelling at the summer pole and downwelling at the winter pole. Air rising will expand and cool resulting in a cold summer mesopause and conversely downwelling air results in compression and associated increase in temperature at the winter mesopause. In the mesosphere the summer-to-winter circulation is due to gravity wave dissipation, which deposits momentum against the mean east–west flow, resulting in a small north–south circulation.The Physics of Atmospheres, John Theodore Houghton, section and references therein of The general circulation of the middle atmosphere In recent years the mesopause has also been the focus of studies on global climate change associated with increases in CO2.
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Alternative interpretations of Carolina bays that are no longer viewed favorably by most geologists include: #the action of sea currents when the area was under the ocean; #the upwelling of ground water at a later time; #the formation of siliciclastic karst by solution of subsurface material during glacial sealevel lowstands; #extraterrestrial impact hypotheses: Comet or meteorite impact hypotheses were popular during the 1940s and 1950s. However, geologists later determined the depressions are too shallow and that they lack evidence for them to be impact features. Reports of magnetic anomalies do not show consistency across the sites, and there are no meteorite fragments, shatter cones, or planar deformation features. None of the necessary evidence for impacts is present, and comet or meteorite impact hypotheses have been rejected.
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The Cape Floral Region is a thin coastal strip and a botanic hotspot which developed at the confluence of the Benguela Upwelling and Agulhas Current. According to what professor Curtis Marean calls the "Cape Floral Region – South Coast Model" for the origins of modern humans, the early hunter-gatherers survived on shellfish, as well as geophytes, fur seal, fish, seabirds, and wash-ups found on the exposed Agulhas Bank. The bank slopes into the sea and a reconstruction of how the coastline has changed over 440 kya shows that the coast during the Pleistocene was located as far as from the present coast. The present South African southern coastal plain (SCP) is still separated from the rest of Africa by the Cape Fold Belt.
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Fishing boats in Quellón, Chiloé with Corcovado volcano in the background Humboldt Current Two live individuals of Concholepas concholepas; the one on the left has been turned over to show the underside of the large muscular foot Fishing in Chile is a major industry with a total catch of 4,442,877 tons of fish in 2006.Chilean National Fisheries Service As of 2010, Chile has the seventh largest commercial catch in the world.The Economist With over 4,000 km (2,500 miles) of viable coastline, fishing has been a vital resource for small-scale business and family development for hundreds of years. Due to the Humboldt Current, the Chilean Sea is considered among the most productive marine ecosystems in the world as well as the largest upwelling system.
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The courses of the warm Agulhas current (red) along the east coast of South Africa, and the cold Benguela current (blue) along the west coast, originating in the Indian Ocean and Atlantic Ocean respectively. Note that the Benguela current does not originate from Antarctic waters in the South Atlantic Ocean, but from upwelling of water from the cold depths of the Atlantic Ocean against the west coast of the continent. The two currents do not "meet" anywhere along the south coast of Africa.Source waters for the Benguela include cold upwelled waters from the depths of the Atlantic Ocean close inshore, joined further off-shore by nutrient poor water that has crossed the Southern Atlantic from South America as part of South Atlantic Gyre.
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This is unexpected for the classic model of a hot, buoyant plume in the mantle. However, it has been shown that other plumes display highly variable surface heat fluxes and that this variability may be due to variable hydrothermal fluid flow in the Earth's crust above the hotspots. This fluid flow advectively removes heat from the crust, and the measured conductive heat flow is therefore lower than the true total surface heat flux. The low heat across the Hawaiian Swell indicates that it is not supported by a buoyant crust or upper lithosphere, but is rather propped up by the upwelling hot (and therefore less-dense) mantle plume that causes the surface to rise through a mechanism known as "dynamic topography".
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The current is circumpolar due to the lack of any landmass connecting with Antarctica and this keeps warm ocean waters away from Antarctica, enabling that continent to maintain its huge ice sheet. Associated with the Circumpolar Current is the Antarctic Convergence, where the cold Antarctic waters meet the warmer waters of the subantarctic, creating a zone of upwelling nutrients. These nurture high levels of phytoplankton with associated copepods and krill, and resultant foodchains supporting fish, whales, seals, penguins, albatrosses, and a wealth of other species. The ACC has been known to sailors for centuries; it greatly speeds up any travel from west to east, but makes sailing extremely difficult from east to west, although this is mostly due to the prevailing westerly winds.
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View of the Cape Peninsula showing the City of Cape Town and False Bay in the background from the International Space Station, May 2019 The Cape of Good Hope; looking towards the west, from the coastal cliffs above Cape Point. Cape Town City Centre, Table Mountain, the main mountains and peaks that make up the Peninsula, and the Cape of Good Hope. The courses of the warm Agulhas current (red) along the east coast of South Africa, and the cold Benguela current (blue) along the west coast. Note that the Benguela current does not originate from Antarctic waters in the South Atlantic Ocean, but from upwelling of water from the cold depths of the Atlantic Ocean against the west coast of the continent.
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Because El Niño's warm pool feeds thunderstorms above, it creates increased rainfall across the east-central and eastern Pacific Ocean, including several portions of the South American west coast. The effects of El Niño in South America are direct and stronger than in North America. An El Niño is associated with warm and very wet weather months in April–October along the coasts of northern Peru and Ecuador, causing major flooding whenever the event is strong or extreme. The effects during the months of February, March, and April may become critical along the west coast of South America, El Niño reduces the upwelling of cold, nutrient-rich water that sustains large fish populations, which in turn sustain abundant sea birds, whose droppings support the fertilizer industry.
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Ocean deoxygenation has led to suboxic, hypoxic, and anoxic conditions in both coastal waters and the open ocean. Since 1950, more than 500 sites in coastal waters have reported oxygen concentrations below 2 mg liter−1, which is generally accepted as the threshold of hypoxic conditions. Several areas of the open ocean have naturally low oxygen concentration due to biological oxygen consumption that cannot be supported by the rate of oxygen input to the area from physical transport, air-sea mixing, or photosynthesis. These areas are called oxygen minimum zones (OMZs), and there is a wide variety of open ocean systems that experience these naturally low oxygen conditions, such as upwelling zones, deep basins of enclosed seas, and the cores of some mode-water eddies.
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Also present within the dark region of the storm were sharp band-lines potentially indicating unseen high winds, despite exact measurements having never been taken. The bright central region representing the pupil of they eye-like shape was formed by white methane-ice clouds upwelling from the center of the storm. Within the chaos of these central clouds are some larger structures, including a distinct V-shape on the East side of the storm indicating the storm's believed clockwise rotation. These clouds are composed of the same methane-ice that forms similar clouds called "companion clouds" present near the edges of other large storms on the planet; however, the Small Dark Spot did not have any of these companion clouds apparent in its 1989 observation.
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Detail of the cliff that overlooks the upwelling at Bèze Entrance to the Bèze cave The Crétanne cave is made of limestone. The set of galleries that constitutes the underground Bèze river have developed in layers of limestones that are not very thick ( on average) and were formed in the upper part of the Oxfordian or Astartian ageas. This formation overlays a thick mass of limestone of quite variable nature from the Rauracian and Sequanian ages, with thickness of over , which constitutes the basement of the limestone plateaus to the north of Bèze. The source is covered by limestone and marl of the Kimmeridgian age, which form a small cuesta visible to the southeast of the village of Bèze, under the compact limestone of the Portland Group.
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A zone of strong easterly Ekman flow propagates westward into the central Pacific basin near the date line during December–February. Relaxation of trade winds in the eastern coincided with the eastward propagation of the geostrophic flow east of 240°E (particularly in February), while westward currents dominated in the central and western equatorial region, which then reversal in the east, with weak local trade winds and weak upwelling along the coast, coincided with the onset of warm SST anomaly.(This anomaly first appeared off South America in March and April). Geostrophic current anomaly, like a Kelvin wave signature propagating eastward to South America between December and April can be easily discerned, and this arrival to South America also coincided with the above-mentioned SST anomaly onset.
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The port of Poti, Georgia The Black Sea supports an active and dynamic marine ecosystem, dominated by species suited to the brackish, nutrient-rich, conditions. As with all marine food webs, the Black Sea features a range of trophic groups, with autotrophic algae, including diatoms and dinoflagellates, acting as primary producers. The fluvial systems draining Eurasia and central Europe introduce large volumes of sediment and dissolved nutrients into the Black Sea, but the distribution of these nutrients is controlled by the degree of physiochemical stratification, which is, in turn, dictated by seasonal physiographic development. During winter, strong wind promotes convective overturning and upwelling of nutrients, while high summer temperatures result in a marked vertical stratification and a warm, shallow mixed layer.
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The movement of Alaskan and northern ocean currents southward down the west coast results in much cooler ocean temperatures than at comparable latitudes on the east coast of the United States, where ocean currents come from the Caribbean and tropical Atlantic. The cooler ocean current along the west coast also makes summer temperatures cooler on the west coast compared to the east coast. For example, Half Moon Bay at 37°N has no month with an average high above and San Francisco often stays below in summer, while Virginia Beach, VA, close to the same latitude, has six months when high temperatures are above . Additionally, extensive upwelling of colder sub-surface waters occurs, caused by the prevailing northwesterly winds acting through the Ekman Effect.
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Surface outflow drives a deep water inflow which is strongly influenced by upwelling and downwelling conditions on the nearby continental shelf. The nutrient-rich, terrestrial freshwater discharge and the nutrient-rich, cool, salty upwelled water support a diverse and abundant ecosystemPawlowicz and McClure, 2010 Folger Pinnacle, located atop a shallow reef, has dense mats of sponges, ascidians and encrusting algae. There are numerous types of sessile (bottom attached) organisms including sponges, anemones, bryozoans, tunicates, and barnacles. Since this is a rockfish conservation area, there is a wide variety of rockfish (yellowtail, China, quillback, Puget Sound, black, and blue) in addition to many other fish (kelp greenling, lingcod, flatfish, wolfeels), molluscs (giant Pacific octopus, mussels, swimming scallops, and snails), and echinoderms (seastars, sea cucumbers, and urchins).
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The low pressure group has formed along geotherms around 20-30 °C/km, which are comparable to those during the underplating of plateau bases. Mantle upwellings add mafic basement to the crust and the pressure due to the cumulation thickness may reach the requirement of low pressure TTG production. The partial melting of the plateau base (which can be induced by further mantle upwelling) would then lead to low pressure TTG generation. The high pressure TTGs have experienced geotherms lower than 10 °C/km, which are close to modern hot subduction geotherms experienced by young slabs (but around 3 °C/km hotter than other modern subduction zones), whilst the geotherms for the most abundant TTG subseries, medium pressure group, are between 12 and 20 °C/km.
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Four humpbacks feeding at Stellwagen Bank The sanctuary lies within Massachusetts Bay, east of Boston, east of Gloucester, and north of Provincetown, Massachusetts. The heart of the sanctuary is Stellwagen Bank, an underwater plateau stretching north to south, and six miles (10 km) across at its widest, near the southern end. The bank is, on average, 100 to 120 feet (30 to 40 meters) below the surface, while surrounding waters to the west are over deep and to the northeast as deep as 600 feet (200 m). The steep sides of the plateau cause deep-water currents to rise up when they hit the bank; this upwelling brings with it nutrients and minerals from the bottom, feeding the local ecosystem.
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Unlike polynyas, which tend to occur, and remain, at a given location, leads are transient features that can form anywhere in an ice-covered ocean. Moreover, while the origin of polynyas is linked with either warm air current circulation from the coastline or a warm water upwelling, the driving force behind lead formation is a state of stress, either wind- or current-induced, within the plane of the ice. Lead formation is therefore tied in with synoptic-scale weather patterns, typically lasting a few days. Also, because the open water within a lead tends to quickly refreeze, the contribution of leads to heat exchange and water vapour output to the atmosphere is significantly less than that of polynyas, where refreezing of the open water is prevented.
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In 2018, MOTE Marine in Sarasota, FL updated their frequently asked questions to make it more clear that nutrients (nitrogen is a nutrient found in fertilizer) can grow K. brevis. Along the west coast of Florida, the early phase of K. brevis blooms are initiated by northerly winds, resulting in upwelling events that cause nutrients to rise towards the surface of the water and transport multiple Karenia cell species towards the shore. Here they concentrate and either continue to grow or are taken up by onshore winds that spread the cells over beaches and near shore communities. It has been shown that K. brevis blooms are limited by available nitrogen (N) or phosphorus (P), but until recently it was not clear what sources K. brevis was utilizing for these key developmental nutrients.
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The most likely proposition is some combination of the upwelling of subsurface nutrients, land runoff (agricultural and sugar plantations, cattle ranches, golf courses, theme parks, septic systems, etc.) N2-fixation, drainage from phosphate mines and atmospheric deposition provides the necessary support for the blooms. In addition to the breaking of the cells by waves, K. brevis cells can die because N-limitation directly affects the growth potential of blooms and the toxicity of K. brevis cells that comprise them. When N-limitation is present, intracellular brevetoxin concentrations (fg/μm3) increased up to 2.5-fold in laboratory cultures, implying that during periods of N-limitation of algal growth, there is a higher chance of brevetoxin influx into the marine food web. The toxin content per cell increases when algal growth becomes P-limited.
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In situ, controlled perturbation experiments, often conducted over weeks to months, can provide inference concerning the response of natural communities to ocean acidification that is difficult or impossible to derive from laboratory experiments. Studies conducted in situ can include the effects of potentially important factors such as natural variation in planktonic food resources, larval abundance, changes in predators or competitors, as well as oceanographic conditions (e.g. changes in upwelling intensity). Drawing on the experience of Free Air CO2 Enrichment (FACE) experiments used to investigate the response of terrestrial plant communities to rising atmospheric CO2 levels, the scientific community has developed an analogous approach, Free Ocean CO2 Enrichment (FOCE) experiments, for studying marine communities, and to complement a range of experimental methods and technologies for ocean acidification studies research.
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After crossing the Yucatan peninsula, Opal reentered the Gulf of Mexico and passed over an eddy shed by the Loop Current. Within a fourteen-hour period, sea surface pressure dropped from 965 to 916 hectaPasals, surface winds increased from 35 to 60 meters/second, and the storm condensed from a radius of 40 kilometers to 25 kilometers. Prior to the storm, the 20 °C isotherm was located at a depth between 175 and 200 meters, but was found 50 meters shallower after the storm had passed. While the majority of this hurricane induced cooling of the mixed layer was attributed to upwelling (due to Ekman divergence), another 2000 to 3000 watts/meter squared were estimated to be lost through heat flux at the air-water interface of the storm's core.
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Piper, D. & Dean, W.E. 2002: Trace-element deposition in the Cariaco Basin under sulfate reducing conditions—a history of the local hydrography and global climate, 20 ka to the present. US Geological Survey Professional Paper 1670, 41 pp. geochemical studies, with alkenones,Herbert, T.D. & Schuffert, J.D. 2000: Alkenone unsaturation estimates of sea-surface temperatures at site 1002 over a full glacial cycle. Proceedings of the Ocean Drilling Program, Scientific Results 165, 239-247 Mg/Ca,Lea, D.W., Pak, D.K., Peterson, L.C. & Hughen, K.A. 2003: Synchroneity of Tropical and High-Latitude Atlantic temperatures over the Last Glacial Termination. Science 301, 1361-1364. and micropaleontological, with foraminifera,Peterson, L.C., Overpeck, J.T., Kipp, N.G. and Imbrie, J. 1991: A high–resolution late Quaternary upwelling record from the anoxic Cariaco Basin, Venezuela, Paleoceanography 6, 99–119.
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The Upwelling is a band with roots in the New York City, Washington, D.C., and Boston areas that currently resides in Queens. The band was founded by and originally consisted of brothers Ari and Josh Ingber on guitar and drums respectively. Their self-recorded, self-titled EP achieved the rare feat of finding distribution without being released by a label, partly due to its "Recommended" status by the Virgin Megastore—the first time the retail chain awarded such an honor to an unsigned band or an EP. Without an agency or a label, the band won Karma Production's Ireland tour, a Sonic Bid's contest. They also drew attention from their peers: In 2005, Third Eye Blind's Stephan Jenkins heard a copy of the band's 2005 EP and began taking the band on the road.
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With a symmetric ring of deep convection surrounding a distinct eye, Gaston ultimately peaked with sustained winds of 120 mph (195 km/h) six hours later. A mid-level trough moving southeastward across the North Atlantic eroded a series of ridges steering Gaston, causing the system to drift north and northeast. Cold water upwelling and an eyewall replacement cycle caused Gaston to weaken on August 29, although the cyclone unexpectedly re-intensified to 120 mph (195 km/h) for a second time around 00:00 UTC on August 31\. Later that day, it began encountering increasingly cool waters and a higher shear, leading the storm to fall below major hurricane status by 18:00 UTC on August 31, and below hurricane intensity by 12:00 UTC on September 2\.
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This work has contributed to a better, more mechanistic understanding of the connectedness of climate processes across the Northern Hemisphere, from Siberia all the way to the US West Coast. More recently, they are looking at how these same processes manifest in long term data on winds along the Central and Southern California coast to see how climate variability signals can affect local winds in the Santa Barbara Channel area. Variation in wind strength has ecological effects by driving upwelling and also has a practical implication for local mariners: if climate change causes more windy days, there are fewer days for boating and fishing in the sanctuary. Additionally, the sanctuary’s ongoing maintenance of a network of moorings provides a continuous data series of oceanographic conditions in nearshore waters that is informing climate variability studies.
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On July 29, the NHC noted that an area of low pressure was forecast to form well south of Mexico. A large mass of convection developed south of Acapulco, Mexico two days later, eventually coalescing into the record-tying eighth tropical cyclone to form in the East Pacific during the month of July. The depression intensified into Tropical Storm Howard by 09:00 UTC on August 1, and although the cyclone struggled with westerly wind shear and upwelling, it ultimately attained peak winds of 60 mph (95 km/h) a day later. Continuing on its west- northwest path, Howard entered cooler waters and a more stable environment, and the combination of the two factors caused the cyclone to degenerate into a remnant low well west of Baja California by 21:00 UTC on August 3.
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There have been many attempts in various countries to introduce high technology to cultivate detached plants growth in tanks on land in order to reduce labor, but they have yet to attain commercial viability. There has been considerable discussion as to how seaweeds can be cultivated in the open ocean as a means to regenerate decimated fish populations and contribute to carbon sequestration. Notably, Tim Flannery has highlighted how growing seaweeds in the open ocean, facilitated by artificial upwelling and substrate, can enable carbon sequestration if seaweeds are sunk below a depth of one kilometer. Similarly, the NGO Climate Foundation and a number of permaculture experts have posited that the offshore mariculture of seaweed ecosystems can be conducted in ways that embody the core principles of permaculture, thereby constituting Marine Permaculture.
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Later that day, Luis was further upgraded to a Category 4 hurricane. Early on September 3, maximum sustained winds reached 150 mph (240 km/h), though the lowest pressure in relation to Luis was not recorded until September 8\. After weakening slightly, Luis passed near Antigua and made landfall in Barbuda early on September 5, before brushing Saint Barthélemy, Saint Martin, and Anguilla. After remaining a major hurricane for a week, Luis weakened to a Category 2 hurricane while northeast of the Bahamas on September 8; the weakening was possibly as a result of the storm crossing over decreasing ocean temperature due to upwelling from Hurricane Felix. On September 10, Luis rapidly accelerated northeastward and weakened to a Category 1 hurricane. Luis made landfall on the Avalon Peninsula of Newfoundland early on September 11.
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Various processes have been proposed to explain the volcanism in the Basin and Range province. These include tectonic spreading which triggered the upwelling of mantle material, convection within the mantle owing to temperature and viscosity differences, the aftereffects of Proterozoic crustal boundaries, mantle currents and release of water by the slab of the Farallon Plate and the delamination of crustal material. There are a number of volcanic fields in Eastern California and Big Pine is one of these. Volcanic activity at Big Pine and Coso volcanic fields is linked to the tectonic spreading of the Basin and Range province, and vents at Big Pine are associated with faults such as the Owens Valley fault, the Sierra Nevada fault and the White Mountains fault; faults have offset lava flows of the field.
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The Antarctic Circumpolar Current moves perpetually eastward – chasing and joining itself, and at in length – it comprises the world's longest ocean current, transporting of water – 100 times the flow of all the world's rivers. Several processes operate along the coast of Antarctica to produce, in the Southern Ocean, types of water masses not produced elsewhere in the oceans of the Southern Hemisphere. One of these is the Antarctic Bottom Water, a very cold, highly saline, dense water that forms under sea ice. Associated with the Circumpolar Current is the Antarctic Convergence encircling Antarctica, where cold northward-flowing Antarctic waters meet the relatively warmer waters of the subantarctic, Antarctic waters predominantly sink beneath subantarctic waters, while associated zones of mixing and upwelling create a zone very high in nutrients.
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The sediments of the Bostobe Formation consist mainly of clays and sandstones, and correspond to floodplain and estuarine environments in a subtropical to tropical climate. These different biotopes were located on the west coast of the Asian continent of the time, on the edge of the ancient Turgai Sea which connected the Tethys to the Arctic Ocean. The shallow marine waters west of this fluvial coastal plain were the site of intense organic productivity due to upwelling conditions caused by strong winds from the mainland. These winds were also the cause of a significant aridification of the climate in this region during the Santonian and early Campanian, causing a change in the flora of angiosperms, with a rarefaction of broad-leaved forms and a proliferation of small and narrow-leaved species of the family Ulmaceae.
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The Central Atlantic magmatic province (CAMP) is the Earth's largest continental large igneous province, covering an area of roughly 11 million km2. It is composed mainly of basalt that formed before Pangaea broke up in the Mesozoic Era, near the end of the Triassic and the beginning of the Jurassic periods. The subsequent breakup of Pangaea created the Atlantic Ocean, but the massive igneous upwelling provided a legacy of basaltic dikes, sills, and lavas now spread over a vast area around the present central North Atlantic Ocean, including large deposits in northwest Africa, southwest Europe, as well as northeast South and southeast North America (found as continental tholeiitic basalts in subaerial flows and intrusive bodies). The name and CAMP acronym were proposed by Andrea Marzoli (Marzoli et al.
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If the sedimentation rate is low (about 1 cm/yr), the organic carbon content is low (about 1% ), and oxygen is abundant, aerobic bacteria can use up all the organic matter in the sediments faster than oxygen is depleted, so lower-energy electron acceptors are not used. But where sedimentation rates and the organic carbon content are high, which is typically the case on continental shelves and beneath western boundary current upwelling zones, the pore water in the sediments becomes anoxic at depths of only a few centimeters or less. In such organic-rich marine sediments, sulfate then becomes the most important terminal electron acceptor due to its high concentration in seawater, although it too is depleted by a depth of centimeters to meters. Below this, methane is produced.
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The three "blobs" of warm water can be seen off the North American coast, ranging from Alaska to Mexico, seen in this graphic dated 1 September 2014. Initially the Blob was reported as being wide and deep. It later expanded and reached a size of long, wide, and deep, in the month of June 2014 when the term "The Blob" was coined. The Blob now hugs the coast of North America from Mexico to Alaska and beyond, stretching more than , and has formed three distinct patches: the first, off the coast of Canada, Washington, Oregon, and northern California, a region known to oceanographers as the Coastal Upwelling Domain; the second in the Bering Sea off the coast of Alaska; and the third and smallest off the coast of southern California and Mexico.
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The water that issues from seafloor hydrothermal vents consists mostly of sea water drawn into the hydrothermal system close to the volcanic edifice through faults and porous sediments or volcanic strata, plus some magmatic water released by the upwelling magma. In terrestrial hydrothermal systems, the majority of water circulated within the fumarole and geyser systems is meteoric water plus ground water that has percolated down into the thermal system from the surface, but it also commonly contains some portion of metamorphic water, magmatic water, and sedimentary formational brine that is released by the magma. The proportion of each varies from location to location. In contrast to the approximately ambient water temperature at these depths, water emerges from these vents at temperatures ranging from up to as high as .
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A thermocline is a sharp temperature drop at depth; it varies during the year, with location, and over long periods of time. As the thermocline depth increases El-Nino events are more likely; however, during the peak of the event energy is dissipated and the thermocline decreases depth, possibly to below normal levels so the a strong La-Nina event can results. The world's oceans, particularly the depths of the Atlantic, are believed to be a sink for that is adsorbed at the polar regions, as this builds into the Pacific the upwelling and warming of water can bring -rich waters trapped in the cold pressurized bottom layers to the surface. Local increases of occur which allow more heat-trapping; the La-Nina may be mild or aborted early in the process.
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The dive maxim, "stop, breathe, think, act" is generally a good response, but it is not appropriate for all diving emergencies. This response assumes that both time and an adequate supply of breathing gas are available, and though this is often true, some situations require immediate learned responses which must be habituated by education, training and repetitive practice to overcome inappropriate instinctive and natural reflexive responses. For example, a diver should exhale whenever ascending to prevent lung overexpansion injuries, and if the diver is subject to a collision or sudden upwelling underwater, the natural reaction may be to tense up and hold his breath, particularly if the breathing gas supply is interrupted at the same time. This reaction could prove fatal if the diver is lifted sufficiently to cause lung overexpansion.
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There is some disagreement about the origin of Bowie seamount: Geological studies indicate that the Kodiak-Bowie Seamount chain may have formed above a center of upwelling magma called a mantle plume. The seamounts comprising the Kodiak-Bowie Seamount chain would be formed above the mantle plume and carried away from the mantle plume's magmatic source as the Pacific Plate moves in a northwesterly direction towards the Aleutian Trench, along the southern coastline of Alaska. The volcanic rocks which make up some of the seamounts in the Kodiak-Bowie Seamount chain are unusual in that they have an acid-neutralizing chemical substance like typical ocean-island basalts but a low percentage of strontium as found at mid-ocean ridge basalts. However, the strontium-bearing volcanic rocks comprising Bowie Seamount also contain lead.
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The species is known to be abundant along the western coasts of South America, ranging from Cape Horn (55°58’S) to Arica (18°28’S), with the northernmost record at 12°30’S near Pucusana (Peru). Although the southern right whale dolphin is considered abundant, only few confirmed records of the species in the Eastern South Pacific exist. Preliminary boat surveys and stranding and fishery records suggest that southern right whale dolphins may be one of the most common species of cetacean in northern Chile. The range extends until offshore north of 40°S and off the southern coast of Chile and it has been suggested that at least a part of this Chilean population migrates northbound in the austral winter and spring, when the coastal component of the cold Humboldt Current and cool coastal upwelling are strongest.
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One proposal is that the hiatus was a part of natural climate variability, specifically related to decadal cooling in the eastern equatorial Pacific in the La Niña phase of the El Niño–Southern Oscillation (ENSO). This has been explained as due to unprecedented strengthening of Pacific trade winds in the last 20 years, so that surface warming has been substantially slowed by increased subsurface ocean heat uptake caused by increased subduction in the Pacific shallow overturning cells, and increased equatorial upwelling in the central and eastern Pacific. A March 2014 study found that climate models assuming natural variability which matched subsequent observations of ENSO phasing had produced realistic estimates of 15-year trends. A study published on August 3, 2014 reported that the rapid warming of the Atlantic Ocean has increased trade winds, thereby cooling temperatures in the Pacific Ocean.
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However, the mechanisms causing the NE movement of the CLIP remains unclear, especially considering the subduction in the Costa Rica-Panama arc initiated during the Campanian (83–72 Ma). The Galápagos hotspot is probably responsible for the main plume-related magmatic event 90 Ma, whilst the 76 Ma and 55 Ma event are related to lithospheric thinning in the Central Caribbean. 40Ar/39Ar dating have determined that the main magmatism occurred (Ma) while a second pulse occurred 81-69 Ma. Around 86 Ma the arrival of a large plume initiated the Galápagos hotspot which resulted in volcanism over large parts of the Caribbean Plate and north-west South America. Renewed volcanism about 75 Ma has been attributed to either the Galápagos hotspot, thinning of the lithosphere coupled with associated melting and upwelling of plume-head material, or both.
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Wind shear decreased again and the storm crossed into warmer ocean temperatures, allowing Florence to re-strengthen into a hurricane on September 9. On the next day, Florence underwent a second bout of rapid intensification, reaching Category 4 intensity again late on September 10\. After additional strengthening, the cyclone reached its peak intensity around 18:00 UTC on September 11, with maximum sustained winds of 150 mph (240 km/h) and a minimum barometric pressure of . The system steadily weakened thereafter due to upwelling and eyewall replacement cycles, with the storm falling below major hurricane intensity on September 13 as it neared the Carolinas. Florence then slowed significantly due to collapsed steering currents and made landfall near Wrightsville Beach, North Carolina, as a Category 1 with winds of 90 mph (150 km/h) around 11:15 UTC on September 14\.
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The Attawapiskat kimberlite field is a field of kimberlite pipes in the Canadian Shield located astride the Attawapiskat River on Attawapiskat First Nation land. It is thought to have formed about 180 million years ago in the Jurassic period when the North American Plate moved westward over a centre of upwelling magma called the New England hotspot, also referred to as the Great Meteor hotspot. The area is composed of 18 kimberlite pipes of the Attawapiskat kimberlite field, 16 of which are diamondiferous; the Victor Mine sits on top of the Victor pipe and mines from Victor Main and Victor Southwest which have appeared close enough to the surface to be used in an open-pit mine. The Victor Kimberlite is a composition of pyroclastic crater facies and hypabyssal facies, and is considered to have a highly variable diamond grade.
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In its more modern form, conceived in the 1970s, it tries to reconcile in one single geodynamic model the horizontalistic concept of Plate tectonics, and the verticalistic concepts of mantle plumes, by the gravitational movement of plates away from major domes of the Earth's crust. The existence of various supercontinents in Earth history and their break-up has been associated recently with major upwellings of the mantle. It is classified together with mantle convection as one of the mechanism that are used to explain the movements of tectonic plates. It also shows affinity with the concept of hot spots which is used in modern-day plate teconics to generate a framework of specific mantle upwelling points that are relatively stable throughout time and are used to calibrate the plate movements using their location together with paleomagnetic data.
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From November 29 up until late December 1, Kammuri was unable to strengthen to previous estimates due to its near stationary movement as a result of weak steering currents, upwelling itself consequently. On December 2, the system tracked westward at a much faster speed of 12 mph (19 km/h) and rapidly intensified over warm Philippine Sea waters, before making landfall in the Bicol Region of the Philippines at peak intensity as a category 4-equivalent typhoon. Upon leaving the Philippines, Kammuri significantly weakened as wind shear increased and interaction with the Philippine islands caused the structure of the system to degrade rapidly, and throughout December 3, it stayed as a category 1-equivalent typhoon, with its outer rainbands barely on land. By December 4, Kammuri drifted over the South China Sea as a weakening tropical storm.
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Since then, the SOLAS community has grown into a worldwide network with 1075 members and 30 national networks around the world. Development and implementation of the SOLAS science plan is guided by a scientific steering committee (SSC) composed of international experts covering a broad spectrum of disciplines, including atmospheric chemistry, oceanography, marine biology, and legal sciences. SOLAS science is currently organised around five core research themes, namely: 1) Greenhouse gases and the oceans; 2) Air-sea interface and fluxes of mass and energy; 3) Atmospheric deposition and ocean biogeochemistry; 4) Interconnections between aerosols, clouds, and marine ecosystems; and 5) Ocean biogeochemical control on atmospheric chemistry. The five SOLAS core research themes are complemented by cross-cutting themes on key environments (such as upwelling systems, polar oceans, and the Indian Ocean), as well as on evaluating the environmental efficacy and impacts of climate intervention proposals, policy decisions, and societal developments.
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Because of gravitational sinking of particulate material (such as plankton, dead or fecal material), nutrients are constantly lost from the photic zone, and are only replenished by mixing or upwelling of deeper water. This is exacerbated where summertime solar heating and reduced winds increases vertical stratification and leads to a strong thermocline, since this makes it more difficult for wind mixing to entrain deeper water. Consequently, between mixing events, primary production (and the resulting processes that leads to sinking particulate material) constantly acts to consume nutrients in the mixed layer, and in many regions this leads to nutrient exhaustion and decreased mixed layer production in the summer (even in the presence of abundant light). However, as long as the photic zone is deep enough, primary production may continue below the mixed layer where light-limited growth rates mean that nutrients are often more abundant.
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As the adjacent diagram shows, if ammonium is indeed nitrified to nitrate in the ocean's surface waters it essentially "short circuits" the deep pathway of nitrate. In practice, this would lead to an overestimation of new production and a higher f-ratio, since some of the ostensibly new production would actually be fuelled by recently nitrified nitrate that had never left the surface ocean. After including nitrification measurements in its parameterisation, an ecosystem model of the oligotrophic subtropical gyre region (specifically the BATS site) found that, on an annual basis, around 40% of surface nitrate was recently nitrified (rising to almost 90% during summer). A further study synthesising geographically diverse nitrification measurements found high variability but no relationship with depth, and applied this in a global-scale model to estimate that up to a half of surface nitrate is supplied by surface nitrification rather than upwelling.
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A disturbance within the ITCZ was first identified over the southwestern Caribbean Sea on October 13, crossing Central America and entering the East Pacific over the subsequent three days. Deep convection steadily increased and organized into curved spiral bands, leading to the formation of a tropical depression by 00:00 UTC on October 20; six hours later, it was upgraded to Tropical Storm Raymond. Steered northwest by a series of ridges to the cyclone's north, Raymond rapidly intensified amid warm ocean temperatures and low wind shear, becoming a hurricane by 00:00 UTC on October 21 and attaining Category 3 status with peak winds of 125 mph (205 km/h) by 18:00 UTC that day. Executing a clockwise loop, significant cold water upwelling and increased upper-level winds caused the cyclone to weaken abruptly, deteriorating to tropical storm intensity by 06:00 UTC on October 23\.
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Intraplate volcanoes occur in many places of the Western United States, including along the Sierra Nevada, on the Colorado Plateau, the Basin and Range province and the Rio Grande Rift. Lunar Crater volcanic field lies within the Basin and Range province along with other volcanic fields, but in an unusually central position. Upwelling of asthenospheric mantle in response to the tectonic regime of the Basin and Range may be responsible for the eruptive activity there, although other processes have also been proposed such as mantle downwelling and compensating flow in the asthenosphere; older volcanism in the region is related to the subduction of the Farallon Plate. The Basin and Range province has had a complicated geological history and in the last 20 million years features extensional tectonics (tectonic processes involving a dilatation of the crust) represented by normal faults (faults where the downmoving blocks move in a way consistent with gravity).
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Such interference with the background flow subsequently leads to a decrease (enhancement) of the heat fluxes from the ocean toward the atmosphere and therefore an intensification of the positive(negative) SST anomalies, in the warm (cool) hemisphere. Other discernible features of the interhemispheric dipole noted in the aforementioned study, include a strengthened, anomalous downwelling in the hemisphere that is characterized by positive SST anomalies and a respective, less prevalent upwelling in the negative SST anomalies-hemisphere. Furthermore, diabatic heating perturbations are also shown to be linked to cross-equatorial SST changes, with positive anomalies being observed over the warmer Northern hemisphere waters and negative ones over the Southern hemisphere. A strong connection is also found between the tropical Atlantic SST dipole and the overlying atmosphere; enhanced convective patterns and anomalous precipitation appear correlated with warm NH SSTs, whereas the opposite phase is observed across the equator, over the cooler SH waters.
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A severe anoxic event at the end of the Permian would have allowed sulfate-reducing bacteria to thrive, causing the production of large amounts of hydrogen sulfide in the anoxic ocean. Upwelling of this water may have released massive hydrogen sulfide emissions into the atmosphere and would poison terrestrial plants and animals and severely weaken the ozone layer, exposing much of the life that remained to fatal levels of UV radiation. Indeed, biomarker evidence for anaerobic photosynthesis by Chlorobiaceae (green sulfur bacteria) from the Late-Permian into the Early Triassic indicates that hydrogen sulfide did upwell into shallow waters because these bacteria are restricted to the photic zone and use sulfide as an electron donor. The hypothesis has the advantage of explaining the mass extinction of plants, which would have added to the methane levels and should otherwise have thrived in an atmosphere with a high level of carbon dioxide.
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A kelp forest in San Clemente Island, California demonstrating the diversity of life that can be supported by Marine Permaculutre Marine Permaculture is a form of mariculture that reflects the principles of permaculture by recreating seaweed forest habitat and other ecosystems in nearshore and offshore ocean environments. Doing so enables a sustainable long-term harvest of seaweeds and seafood, while regenerating life in the ocean. Marine Permaculture comprises a platform from which seaweed ecosystems can be grown, creating the environmental conditions for primary production and habitat for marine life. Using a system of renewably powered pumps, cool, nutrient-rich waters are brought up from a depth of 100-500 meters, below the nutricline, to the ocean surface, thereby replicating natural overturning circulation processes of ocean upwelling and mitigating against marine heatwaves that have led to ocean stratification and decimated natural macroalgae ecosystems in many regions of the world.
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The first boilers suffered problems with the superheaters and with poor circulation for the tube rows in the centre of the bank, leading to overheating and tube failure. The circulation problems were addressed by re-arranging the feedwater pipes and by placing baffles inside the steam drum, so as to give a more clearly defined circulation. A circulation augmenter, a steel trough, was placed over the tops of the furnace-side tubes, encouraging a single central upwelling flow to above the water level, encouraging steam bubbles to escape and acting as a steam separator before the water re-circulated down the outer-side tubes. In a manner similar to work taking place around the same time on the LMS railway and the development of top feed for steam locomotives, the feedwater was also routed upwards through 'spray pots' and thus passed through the steam space as droplets.
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In Arctic permafrost regions, a related type of ground heaving over hundreds of years can create structures, as high as 60 metres, known as pingos, which are fed by an upwelling of ground water, instead of the capillary action that feeds the growth of frost heaves. Cryogenic earth hummocks are a small formation resulting from granular convection that appear in seasonally frozen ground and have many different names; in North America they are earth hummocks; thúfur in Greenland and Iceland; and pounus in Fennoscandia. Polygonal forms apparently caused by frost heave have been observed in near- polar regions of Mars by the Mars Orbiter Camera (MOC) aboard the Mars Global Surveyor and the HiRISE camera on the Mars Reconnaissance Orbiter. In May 2008 the Mars Phoenix lander touched down on such a polygonal frost-heave landscape and quickly discovered ice a few centimetres below the surface.
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BDRI researchers address a wide range of questions to form a multi-dimensional picture of the marine mammals behaviour and ecology and its relationship to the rest of the planet, including human society. The BDRI research has a multidisciplinary approach with a current focus on four main research projects: \- Cetacean distribution along Galician coast: Current studies by the Bottlenose Dolphin Research Institute BDRI research team principally focus on the cetacean species frequenting the inshore waters of the outer Arousa Firth, however, a new area like Galician coastal waters (north-west Spain) allows for new projects and a more diverse range of issues and species. These waters are characterized by high biodiversity and productive fisheries, supported by nutrient input due to upwelling. Twenty species of cetaceans have been recorded in Galician waters, of which the most abundant appear to be short-beaked common dolphins and bottlenose dolphins. Other species present in the area include harbour porpoises, Risso’s dolphins and long-finned pilot whale.
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This means that the Chilcotin is likely composed of many local volcanic vents, that were of small volumes that fed into the paleo-landscape, and subsequently are found in the major river systems that we see at present. Prior to 16 million years ago, the western Cascade Volcanic Arc stratovolcanoes erupted with periodic regularity for over 27 million years, even as they do today. The ultimate cause of this volcanism is still up for debate, however, the most widely accepted idea is that a back- arc basin behind the Cascadia subduction zone initiated the widespread and voluminous basaltic volcanism. Some centers erupted along pre-existing brittle fault systems while volcanism along its northern portion is most widely believed to have been related to a center of upwelling magma called the Anahim hotspot (similar to that associated with present-day Hawaii), creating the Rainbow, Ilgachuz and Itcha Range shield volcanoes which also in turn form part of the Anahim Volcanic Belt.
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Grundzüge zu einer Theorie der Erdbeben und Vulkanausbrüche. Ed. J. Pock, Graz 1869 A central point of this hypothesis stated earthquakes to be caused by tidal forces acting on subterranean lakes of lava (causing earthquakes) and its upwelling through the earth's crust (causing volcanic eruptions). The strength of these forces being predictable from the positions of the sun and the moon relative to each other, Falb proceeded to postulate "Critical Days" during which geophysical disasters should be more likely to occur. Subsequently he extended this hypothesis, which initially had strong connections to ideas put forward by the French mathematician Alexis Perrey, to include long-term weather forecasting. Falb's hypothesis gained a high public profile when he made predictions that seemed to come true with the 1873 Belluno earthquake and an eruption at Mount Aetna in 1874.Gedanken und Studien über den Vulcanismus mit besonderer Beziehung auf das Erdbeben von Belluno am 29. Juni 1873 und die Eruption des Ätna am 29. August 1874.
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The barrier reef and the Tongue of the Ocean, together with mangrove swamps, rocky tidal pools, and estuaries, provide breeding and growing habitats for a wide variety of young marine life. Andros has a variety of close-to-shore and on-shore ecosystems that may be unique on Earth: tidal inland and ocean blue holes, shallow sand and mud flats, tidal estuaries, mangrove swamps, the pelagic ecozone of the drop-off only from shore, the world's third-largest barrier reef, and huge freshwater aquifers. The marine biosphere is fed by both the teeming life of the mangrove marshes and estuaries on the mainland, and the upwelling of cool water from the Tongue of the Ocean, resulting in an unparalleled variety of sea life. Humpback whales, which are found in all the world's oceans, follow a regular migration route, summering in temperate and polar waters for feeding, and wintering in tropical waters for mating and calving.
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Other papers argue that the lack of a chain of age-progressive seamounts (as in the Hawaiian-Emperor seamount chain), the absence of present-day volcanism, and the elongation of the Bermuda Rise oblique to plate motion are evidence against a hotspot origin for the Bermuda Rise. Peter R. Vogt and Woo-Yeol Jung alternatively attribute the Bermuda Rise to a reorganization of plate tectonics associated with the closing of the Tethys Sea, though noting that shallow processes may not explain the source of the magmatism. A more recent paper finds a thinning in the mantle transition zone under Bermuda, apparently consistent with mantle upwelling and a hot lower mantle below Bermuda. A still more recent paper, based on geochemical analysis of a drill core, suggests that Bermuda volcanism sampled a transient mantle reservoir in the mantle transition zone that was formed by chemical recycling related to subduction during the formation of Pangaea.
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Due to a variety of reasons, ranging from the lack of knowledge among the general public regarding El Niño events to the fact that a volcanic eruption in Mexico from El Chichón distracted many scientists from noticing the telltale signs, this event escaped the notice of the scientific world until 1983. As pointed out by Walter Sullivan, signs began to appear in early 1982, when a noticeable and measurable drop in atmospheric pressure was noted in the central and southeastern Pacific compared to pressures found off the coast of Darwin, Australia. As the year progressed, more and more signs pointed towards an upcoming powerful El Niño event; from the collapse and subsequent reversal of the trade easterlies that traditionally prevent upwelling from occurring in the Western Pacific to the various atmospheric signatures that can all be associated with the El Niño-Southern Oscillation, these indicators all pointed to the fact that one of the most powerful El Niño events of the 20th century had begun.
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The Mississippi embayment represents a break in what was once a single, continuous mountain range comprising the modern Appalachian range, which runs roughly on a north–south axis along the Atlantic coast of the United States, and the Ouachita range, which runs on a rough east–west axis west of the Mississippi River. The ancestral Appalachian-Ouachita range was thrust up when the tectonic plate carrying North America came into contact with the plates carrying South America and Africa when all three became joined in the ancient supercontinent Pangaea about 300 million years ago. As Pangaea began to break up about 95 million years ago, North America passed over a volcanic "hotspot" in the Earth's mantle (specifically, the Bermuda hotspot) that was undergoing a period of intense activity. The upwelling of magma from the hotspot forced the further uplift to a height of perhaps 2–3 km of part of the Appalachian- Ouachita range, forming an arch.
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Evaporation from the Leeuwin current during this period contributes greatly to the rainfall in the southwest region of Western Australia. Typically the Leeuwin Current's speed and its eddies are about 1 knot (50 cm/s), although speeds of 2 knots (1 m/s) are common, and the highest speed ever recorded by a drifting satellite- tracked buoy was . The Leeuwin Current is shallow for a major current system, by global standards, being about 300 m deep, and lies on top of a northwards countercurrent called the Leeuwin Undercurrent. The Leeuwin Current is very different from the cooler, equatorward flowing currents found along coasts at equivalent latitudes such as the southwest African Coast (the Benguela Current); the long Chile-Peru Coast (the Humboldt Current), where upwelling of cool nutrient-rich waters from below the surface results in some of the most productive fisheries; the California Current, which brings foggy conditions to San Francisco; or the cool Canary current of North Africa.
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The Pacific plate, for instance, is essentially surrounded by zones of subduction (the so-called Ring of Fire) and moves much faster than the plates of the Atlantic basin, which are attached (perhaps one could say 'welded') to adjacent continents instead of subducting plates. It is thus thought that forces associated with the downgoing plate (slab pull and slab suction) are the driving forces which determine the motion of plates, except for those plates which are not being subducted. This view however has been contradicted by a recent study which found that the actual motions of the Pacific Plate and other plates associated with the East Pacific Rise do not correlate mainly with either slab pull or slab push, but rather with a mantle convection upwelling whose horizontal spreading along the bases of the various plates drives them along via viscosity-related traction forces. The driving forces of plate motion continue to be active subjects of on-going research within geophysics and tectonophysics.
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Outreach in the Spermonde Islands Williams encouraged scientists to engage meaningfully with the general public as well as with politicians. Her connection with political activism began early in her scientific career; in 1993, she was appointed to a panel of scientists consulting with the assistant secretary of the Interior, and in 2000 she received an Aldo Leopold Fellowship in Environmental Leadership. This activism continued to the end; mere weeks before her death she co-wrote an article commemorating the one-year anniversary of 2017's March for Science in which she urged scientists to become more engaged with the public and politicians. In 2007, she testified before United States Congressional committees about how the Point Arena upwelling center off California's coast provides nutrients to help downstream marine productivity - this is credited with helping pass legislation in June 2015 extending the northern boundary of California's Greater Farallones National Marine Sanctuary in order to better protect the coastal environment.
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However, as part of its post-season routine, the NHC received data from an offshore oil rig in the southeastern quadrant of the system that yielded maximum sustained surface winds of ; as a result, Nate was re-designated as a Category 1 hurricane on the Saffir–Simpson hurricane wind scale while centered approximately 80 mi (130 km) north-northwest of Ciudad del Carmen, Mexico. Following peak intensity, the storm's broad wind field and slow forward motion led to significant ocean upwelling. With cooler sea surface temperatures and low ocean heat content, the coverage of deep convection decreased and Nate weakened to a tropical storm at 0600 UTC on September 9. Tropical Storm Nate approaching Mexico with a nearly convection-free circulation on September 10 While accelerating west-northwest and eventually westward in response to an eastward shift in the ridge over Mexico, Nate moved away from cooler ocean temperatures, briefly allowing it to gain strength on September 10\.
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It is common as a warm front passes over an area with significant snow-pack. It is most common at sea when moist air encounters cooler waters, including areas of cold water upwelling, such as along the California coast (see San Francisco fog). A strong enough temperature difference over water or bare ground can also cause advection fog. Although strong winds often mix the air and can disperse, fragment, or prevent many kinds of fog, markedly warmer and humid air blowing over a snowpack can continue to generate advection fog at elevated velocities up to or more – this fog will be in a turbulent, rapidly moving, and comparatively shallow layer, observed as a few centimetres/inches in depth over flat farm fields, flat urban terrain and the like, and/or form more complex forms where the terrain is different such as rotating areas in the lee of hills or large buildings and so on.
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The surface temperature on an exoplanet is governed by the atmosphere's greenhouse gases (or lack thereof), so an atmosphere can be detectable in the form of upwelling infrared radiation because the greenhouse gases absorb and re- radiate energy from the host star. Ice-rich planets that have migrated inward into orbit too close to their host stars may develop thick steamy atmospheres but still retain their volatiles for billions of years, even if their atmospheres undergo slow hydrodynamic escape. Ultraviolet photons are not only biologically harmful but can drive fast atmospheric escape that leads to the erosion of planetary atmospheres; photolysis of water vapor, and hydrogen/oxygen escape to space can lead to the loss of several Earth oceans of water from planets throughout the habitable zone, regardless of whether the escape is energy-limited or diffusion-limited. The amount of water lost seems proportional with the planet mass, since the diffusion-limited hydrogen escape flux is proportional to the planet surface gravity.
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The discharge of such sequestered carbon was perhaps a direct outcome of the deep Southern Ocean overturning, driven by heightened wind-driven upwelling, and sea-ice retreat, which are directly correlated to the warming of the Antarctic, and also coinciding with the cold events, the Oldest and Younger Dryas, in the north. Throughout the LGM in North America, the east was populated by cold-tolerant conifer forests, while the southeast and northwest of the United States sustained open forests in locations that have closed forests today, which suggests that during the LGM temperatures were cooler and overall conditions were much drier than those that we experience today. There is also indication that the southwest of the United States was much wetter during the LGM compared to today, as there was open forest, where today we see desert and steppe. In the United States, the general variation of vegetation implies an overall fall in temperatures of (at minimum 5 °C), a shift of the westerly storm tracks to the south, and a very steep latitudinal temperature gradient.
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If the wind patterns shift into a cyclonic circulation due to the residence of a low pressure system (rising air induced by warmer ocean temperatures a greater volume of open Arctic Ocean water), this will cause the circulation of the Beaufort Gyre to reverse and flow counter-clockwise. If this occurs, the Coriolis force would bend the flow out and away from the center of the gyre and, instead of the formation of a rising water dome, a depression would form and upwelling of the warmer water from the Atlantic ocean would occur. Oceanographer Andrey Proshutinsky has theorized that if the winds and the gyre's circulation were to weaken, high volumes of freshwater could leak out of the eastern part of the Arctic Ocean into the Northern Atlantic Ocean, impacting the Thermohaline Circulation and thus climate. Due to seasonal sea ice formation, the Beaufort Gyre is difficult to access and thus study in the Northern Hemisphere winter months; the lack of sunlight in these months forces the use of artificial light.. Expanded Academic ASAP. Web.
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Charts of sea surface temperature in and near False Bay in summer and winter In summer False Bay is thermally stratified, with a vertical temperature variation of 5 to 9˚C between the warmer surface water and cooler depths below 50 m, while in winter the water column is at nearly constant temperature at all depths. The development of a thermocline is strongest around late December and peaks in late summer to early autumn. In summer the south easterly winds generate a zone of upwelling near Cape Hangklip, where surface water temperatures can be 6 to 7°C colder than the surrounding areas, and bottom temperatures below 12°C. Northward propagating long period waves are focused in the northeast and northwest parts of False Bay by refraction effects over the shoal waters of Rocky Bank in the mouth of the bay, with measured heights of waves in the area between Steenbras mouth and Kogelbaai being up to twice the height of the waves in the Muizenberg to Strandfontein region for the prevailing southwesterly open ocean swell.
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The Galapagos Islands are believed to be formed from a mantle plume which creates a hotspot of volcanic activity away from plate boundaries where islands then form above it, similar to process that has created the Hawaiian islands. Cerro Azul is at the edge of the upwelling with steep drop offs in the ocean to the West, while the sea is shallower to the east of Isabela Island. Cerro Azul is one of six coalescing volcanoes on Isabela Island: Ecuador, Wolf, Darwin, Alcedo, and Sierra Negra. Cerro Azul is shaped like a large upturned soup bowl and like the other volcanoes on Isabela Island has a large caldera its one at 4x5 km across is one of the smallest. The caldera shows evidence of collapse following eruptive episodes and reaches a depth of 450 m to 650 m below the rim of the caldera, only Wolf Volcano in the Galapagos is as deep. The volcano is 34 by 22 km at maximum and has a volume of 172 km3.
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Lake Ontario's water temperature varies due to upwelling of colder water or warmer pools of surface water creating very localized thermal contrast; the deeper waters of the lake, far from the shore, remain at a near-constant water temperature of , the effect of which is either cooling or warming (in winter). This creates generally warmer nights through the colder season than would otherwise occur. When offshore winds blow in summer, they warm as they near the lakeshore in the evening; conversely, the cooling effect by the lake is most pronounced on spring afternoons, which can affect Toronto even more than other cities on the Great Lakes due its exposure to onshore winds from the east to south-east, on some days, the temperatures can be as much as 10 °C (18 °F) cooler than areas far removed from Lake Ontario, an effect that wanes by summer when the dominant windflow becomes more southwesterly and the lake surface temperature warms. Springs and autumns are shorter seasons than summers and winters, and they feature varied weather with alternating periods of dry, sunny weather and rain.
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Arte Público Press, Houston, Texas (1993) what initiates these blooms and how large a role anthropogenic and natural factors play in their development is unclear. Whether the apparent increase in frequency and severity of algal blooms in various parts of the world is in fact a real increase or is due to increased observation effort and advances in species identification methods is also debated. Increasing temperature, enhanced surface stratification, alteration of ocean currents, intensification or weakening of local nutrient upwelling, stimulation of photosynthesis by elevated CO2, reduced calcification through ocean acidification, and heavy precipitation and storm events causing changes in land runoff and micronutrient availability may all produce contradictory species- or even strain-specific responses. In terms of harmful algal blooms (HABs), we can expect: (i) range expansion of warm-water species at the expense of cold-water species, which are driven poleward; (ii) species-specific changes in the abundance and seasonal window of growth of HAB taxa; (iii) earlier timing of peak production of some phytoplankton; and (iv) secondary effects for marine food webs, notably when individual zooplankton and fish grazers are differentially impacted by climate change.
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In East Tennessee and tidewater Virginia, the vote at the county level showed some strength, but it barely existed in Alabama, Mississippi, and Texas.Presidential Elections, 1789–2008: County, State, and National Mapping of Election Data, Donald R. Deskins, Jr., Hanes Walton, Jr., and Sherman C. Puckett, pg. 250 In a continuation of its collapse there during the 1890 Congressional elections, the Republican Party even struggled in its Midwestern strongholds, where general electoral troubles from economic woes were acutely exacerbated by the promotion of temperance laws and, in Wisconsin and Illinois, the aggressive support of state politicians for English-only compulsory education laws. Such policies, which particularly in the case of the latter were associated with an upwelling of nativist and anti-Catholic attitudes amongst their supporters, resulted in the defection of large sections of immigrant communities, especially Germans, to the Democratic Party. Cleveland carried Wisconsin and Illinois with their 36 combined electoral votes, a Democratic victory not seen in those states since 1852Counting the Votes; Wisconsin and 1856Counting the Votes; Illinois respectively, and which would not be repeated until Woodrow Wilson's election in 1912.
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A tropical wave developed into Tropical Storm Matthew near Barbados on September 28\. Continuing westward under the influence of a mid-level ridge, the storm steadily intensified to attain hurricane intensity by 18:00 UTC on September 29\. The effects of southwesterly wind shear unexpectedly abated late that day, and Matthew began a period of rapid intensification; during a 24-hour period beginning at 00:00 UTC on September 30, the cyclone's maximum winds more than doubled, from 80 mph (130 km/h) to 165 mph (270 km/h), making Matthew a Category 5 hurricane, the first since Hurricane Felix in 2007. Due to upwelling of cooler waters, Matthew weakened to a Category 4 hurricane later on October 1\. Matthew remained a powerful Category 4 hurricane for several days, making landfall near Les Anglais, Haiti, around 11:00 UTC on October 4 with winds of 150 mph (240 km/h). Continuing northward, the cyclone struck Maisí in Cuba early on October 5\. Cuba's and Haiti's mountainous terrain weakened Matthew to Category 3 status, as it began to accelerate northwestwards through the Bahamas. Restrengthening occurred as Matthew's circulation became better organized, with the storm becoming a Category 4 hurricane again while passing Freeport.
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