Ozone depletion has increased the speed of the winds around Antarctica, affecting ocean circulation and sea ice.
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But it certainly supports the idea that ocean circulation and climate were linked during the last ice age.
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The polar sea ice has a direct influence on ocean circulation, weather and regional climate across the globe.
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Other factors could still influence ocean circulation, including tidal forces, planetary rotation, ocean depth, and the configuration of continents.
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That's because ocean circulation — in which deeper, colder waters rise to the surface and replace warmer ocean waters — will be reduced.
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In the 1960s, NASA and other government agencies started launching Earth-orbiting satellites to study weather patterns, ocean circulation and agriculture.
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"It is all extremely uncertain, and depends on ocean-circulation patterns," says Michaela Aschan, a fisheries professor from the University of Tromso.
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He explains that although the ocean circulation can slow, change wouldn't happen overnight, and it's unlikely to spark a new ice age.
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The ocean has the power to accelerate melt, or even stoke the glaciers to start growing again during cooler shifts in ocean circulation.
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Variations in ocean circulation distribute heat, while changes in the sun or in greenhouse gases change the total heat amount in the system.
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This suggests that as we emit more greenhouse gases, deep ocean warming and freshening will continue, potentially altering regional or even global ocean circulation.
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Gawarkiewicz adds that warming will affect fragile deep ocean ecosystems, including cold water corals, as well as large-scale atmospheric and ocean circulation patterns.
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Research published today in Science links these abrupt temperature swings to changes ocean circulation, filling an important gap in our understanding of past climate change.
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Mantle convection can also have a surprising impact on Earth's climate, by affecting the large-scale ocean circulation patterns that move heat around the world.
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Researchers used NASA-developed software called ROCKE-3D to simulate ocean circulation and climates on different types of exoplanets, or planets outside our solar system.
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At sea, most plastics end up in vast rubbish patches fed by ocean circulation patterns, the biggest of which can be found in the north Pacific.
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Greenland melt is an increasingly significant contributor to global sea level rise, affects the ocean food web, and may alter ocean circulation and global weather patterns.
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The climate scientist Wallace Broecker at Columbia had offered a theory that changes in ocean circulation could bring about sudden climate shifts like the Younger Dryas.
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Australia is coming out of its hottest and driest year on record as ocean circulation patterns aligned to heat up the continent and drive away rainfall.
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It was "based on a short-term variation in ocean circulation that was in the news at the time," said another climate change expert, Jim Fleming.
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Lew Gramer, a marine scientist at the University of Miami, has also described a possible "correlation" between climate change and Sargassum's spread due to changes in ocean circulation.
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Other tipping points include rain forest loss in places like the Amazon, monsoon shifts in Africa and Asia, changes to ocean circulation patterns, and coral reef die-offs.
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The visualization is based on observations from the Gravity field and Ocean Circulation Explorer (GOCE), a European Space Agency (ESA) satellite that operated in orbit from 2009 to 2013.
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Melting from Greenland's ice sheet is also likely contributing to colder sea temperatures south of the island, and could have dramatic impacts on ocean circulation and even inhibit hurricane production.
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As white ice is replaced by darker water, less of the sun's energy will be reflected back into space, further warming the world and likely disrupting patterns of ocean circulation.
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"This is really important, because it is possible that certain melt fingerprints or the influence of wind on ocean circulation might cause us to overestimate past sea level rise," said Thompson.
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But darker water absorbs most of that energy, and as it warms may change patterns of ocean circulation in ways that are likely to have far-reaching effects on the world's weather.
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Thwaites' ice shelf has been crumbling, so one group in the collaboration, calling itself Tarsan (Thwaites-Amundsen Regional Survey and Network), will investigate the local effects of ocean circulation and warm air.
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"As scientists, we need to 'connect the dots' from the atmospheric circulation through the ice sheet mass balance to rising sea level and other impacts on ocean circulation and productivity," he wrote in an email.
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The uptake of this heat is contributing to higher temperatures in the oceans, possibly impacting ocean circulation patterns as well as contributing to rising sea levels, which have increased 3.2 millimeters a year since 1993.
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The threat: If the Greenland or Antarctic ice sheets melt quickly and significantly enough, they could pour enough cold, relatively light freshwater into adjacent areas of the ocean to disrupt global ocean circulation, the study finds.
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"Then in 2015, with the onset of El Niño, wind, cloud, and ocean circulation patterns all shifted significantly, resulting in more of that warm water surfacing," NOAA climatologist Gregory Johnson explained to Gizmodo in an email.
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It also draws on a suite of new research published since the last report came out in 2014, highlighting advances in how we understand extreme weather, ocean circulation, melting ice, and humanity's role in the climate.
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The rapid increase in melting came as a decade-long pattern of atmospheric blocking — where warm air stalls over Greenland — converged with a warming phase in the ocean circulation cycle and the long-term warming trend in the climate.
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However, Jahn, who studies Arctic sea ice and ocean circulation in the Far North, said these new findings are worth paying attention to because they help scientists and policy makers see the benefits of stricter greenhouse gas emissions cuts.
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"Large-scale atmospheric conditions and ocean circulation, combined with local wind and current patterns, are driving the record temperatures we've been experiencing this year, but there is little doubt that climate change is also a contributing factor," Gove said.
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Dr. Munk, a scientist-explorer who would expound on his discoveries with exuberance, was sometimes called the "Einstein of the oceans" for his pioneering work in the study of waves, ocean circulation, tides and irregularities in the Earth's rotation.
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The findings relied on data from the Gravity Field and Steady-state Ocean Circulation Explorer (GOCE) satellite, which orbited Earth just 155 miles above the surface until late 2013, when it re-entered the atmosphere at the end of its mission.
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However, while the Larsen C Ice Shelf may not be a sea level rise concern, rising temperatures and changes in land and sea ice across the Antarctic Peninsula are affecting native wildlife and may help disrupt regional — and possibly even global — ocean circulation.
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The idea of a shutdown in the ocean circulation because of global warming was considered more than a decade ago, and while scientists concluded that a weakening of the currents was possible, they said a complete shutdown was unlikely to happen in this century.
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Moreover, it is generally understood that some parts of the globe, including South Florida, will see higher-than-average sea-level rise because of factors like wind and ocean circulation patterns and the region's position relative to Greenland, a massive ice sheet swiftly melting.
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At around 2130 million years ago the world would get colder and drier (due to changes in ocean circulation as South America and Australia move farther away from Antarctica); the rainforests that used to range from the tropics for the Rocky Mountain West and Germany and the like shrink back.
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Just like every other paleontologist, geologist, and biologist working in the New World, he knew what had happened: 3.5 million years ago, Panama collided with South America, cutting off ocean circulation between the Pacific and the Caribbean and creating a land bridge for animals and plants to move between the two continents.
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Those include widespread destruction of the Amazon, reduction of Arctic sea ice, large-scale coral reef die-offs, melting of the Greenland and West Antarctic ice sheets, thawing of permafrost, destabilizing of boreal forests -- which contain vast numbers of trees that grow in freezing northern climes -- and a slowdown of ocean circulation.
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MacLeod, Kenneth. "Cretaceous Climate Tied to Ocean Circulation." Cretaceous Climate Tied to Ocean Circulation. University of Missouri, 29 Oct. 2011. Web.
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The World Ocean Circulation Experiment (WOCE) was a component of the international World Climate Research Program, and aimed to establish the role of the World Ocean in the Earth's climate system. WOCE's field phase ran between 1990 and 1998, and was followed by an analysis and modeling phase that ran until 2002.Ocean Circulation and Climate: World Ocean Circulation Experiment. Retrieved 7 December 2013.
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Currently, Lisiecki designs and develops software for rendering age models and stratigraphy. As well, Lisiecki is creating 3D models of ocean circulation to determine the relationship between orbital forcing and ocean circulation patterns and account for time- variant uncertainties.
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Examine how climate variability affects ocean circulation, weather patterns, the ocean's biochemical environment and marine ecosystems.
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Because the time history of CFC concentrations in the atmosphere is relatively well known, they have provided an important constraint on ocean circulation. CFCs dissolve in seawater at the ocean surface and are subsequently transported into the ocean interior. Because CFCs are inert, their concentration in the ocean interior reflects simply the convolution of their atmospheric time evolution and ocean circulation and mixing.
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In the northern hemisphere the land masses prevent this and the ocean circulation is broken into smaller gyres in the Atlantic and Pacific basins.
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Amy Bower is an American physical oceanographer. She is known for her research on ocean circulation and for being one of very few blind oceanographers.
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The aim of the voyage, according to Reisselman, is to figure out how ocean circulation behaved during past warmer climates, up to three million years ago.
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And the consequences would > certainly not be as dramatic as the 'superstorm' depicted in the movie. > Nevertheless, a major change in ocean circulation is a risk with serious and > partly unpredictable consequences, which we should avoid. And even without > events like ocean circulation changes, climate change is serious enough to > demand decisive action. Environmental activist and Guardian columnist George Monbiot called The Day After Tomorrow "a great movie and lousy science".
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The Nucleus for European Modeling of the Ocean(NEMO) is a general model of ocean circulation developed by a European consortium and used in many countries of Europe.
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Box models are used extensively to model environmental systems or ecosystems and in studies of ocean circulation and the carbon cycle. They are instances of a multi- compartment model.
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The Princeton Ocean Model (POM) is a community general numerical model for ocean circulation that can be used to simulate and predict oceanic currents, temperatures, salinities and other water properties.
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The Parallel Ocean Program (POP) is a three-dimensional ocean circulation model designed primarily for studying the ocean climate system. The model is developed and supported primarily by researchers at LANL.
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The contrast in temperature is only a part of the entire process that is driving the tropical rain belt northward. Another factor that influences the tropical rain belt is ocean circulation. Ocean Overturning Circulation is a process that involves ocean circulation between the Antarctic and Arctic regions. Dargan Frierson explains that in this process, the Northern Hemisphere receives more heat than the Southern because the overturning circulation brings more heat into the Northern Hemisphere as opposed to the Southern.
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Over the course of millions of years, the motion of tectonic plates reconfigures global land and ocean areas and generates topography. This can affect both global and local patterns of climate and atmosphere-ocean circulation. The position of the continents determines the geometry of the oceans and therefore influences patterns of ocean circulation. The locations of the seas are important in controlling the transfer of heat and moisture across the globe, and therefore, in determining global climate.
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The Tethys Seaway was not a gateway, but rather a sea in its own right. Its closing during the Oligocene had significant impact on both ocean circulation and climate. The collisions of the African plate with the European plate and of the Indian subcontinent with the Asian plate, cut off the Tethys Seaway that had provided a low-latitude ocean circulation. The closure of Tethys built some new mountains (the Zagros range) and drew down more carbon dioxide from the atmosphere, contributing to global cooling.
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477-482 The deep waters of the world ocean are formed by convection and diving of dense surface waters during winter periods. To understand the causes of changes in deep ocean circulation, it was necessary to develop a method to reconstruct not only the temperature (which was already known), but also the salinity of surface waters in the past. Duplessy has developed a method based on fractionations that affect stable oxygen isotopes during the water cycle. This has allowed him to reconstruct the salinity of the Atlantic Ocean during the last glacial maximum with sufficient accuracy for major modelling groups to use this data to simulate global ocean circulation using general ocean circulation models.Duplessy J. C. et a, « Surface salinity reconstruction of the North Atlantic Ocean during the last glacial maximum », Oceanologica Acta, 1991, 14, p.
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Ongoing effects include rising sea levels due to thermal expansion and melting of glaciers and ice sheets, and warming of the ocean surface, leading to increased temperature stratification. Other possible effects include large-scale changes in ocean circulation.
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Many geologists believe oceanic anoxic events are strongly linked to slowing of ocean circulation, climatic warming, and elevated levels of greenhouse gases. Researchers have proposed enhanced volcanism (the release of CO2) as the "central external trigger for euxinia".
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When sea ice forms, it pushes the salt out, creating a mass of cold, salty, dense water that sinks to the bottom of the ocean, creating deep ocean currents that affect ocean circulation and the distribution of heat worldwide.
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Bower investigates ocean circulation, including thermohaline circulation (the so-called ocean conveyor belt), using research floats. She also goes on research cruises to retrieve the floats. Bower's research covers the Arctic Ocean and Gulf of Mexico, among other locations.
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Drifters provide real- time information about ocean circulation. They make more accurate and frequent observations of surface current velocity than is possible from remote sensing measurements. A drifter neatly compressed for deployment (left) and with the nylon drogue fully extended (right).
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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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At the time, early computer ocean models such as the Bryan–Cox model (developed in the late 1960s at the Geophysical Fluid Dynamics Laboratory, GFDL, and later became the Modular Ocean Model, MOM)), were aimed mostly at coarse-resolution simulations of the large-scale ocean circulation, so there was a need for a numerical model that can handle high-resolution coastal ocean processes. The Blumberg–MellorBlumberg, A. F. and G. L. Mellor, A description of a three-dimensional coastal ocean circulation model. Three-Dimensional Coastal ocean Models, edited by N. Heaps, 208 pp., American Geophysical Union.
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He established the first reconstructions of the deep ocean circulation during the height of the last ice age and during the last interglacial period. This has led him to highlight a disruption in the functioning of the ocean: the North Atlantic deep water disappears under glacial conditions, accompanied by a general slowdown in large-scale ocean circulation, the intensity of the Gulf Stream and the heat flux transported by the Atlantic Ocean to the coasts of Western Europe.Labeyrie L.D., et al., « Variations in the mode of formation and temperature of oceanic deep waters over the last 125,000 years », Nature, 1987, 327, p.
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In parts of the oceans, especially the north Atlantic Ocean, bioturbation was absent. This may be due to bottom-water anoxia, or by changing ocean circulation patterns changing the temperatures of the bottom water. However, many ocean basins remained bioturbated through the PETM.
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Amy C. Clement is an atmospheric and marine scientist studying and modeling global climate change. Her research focuses on cloud albedo feedbacks, ocean circulation patterns, and the El Niño Southern Oscillation (ENSO). She is currently a professor at University of Miami's Rosenstiel School.
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Kohnen Station is located at , 2892 m above sea level. Higher annual snowfall and sensitivity to conditions over the South Atlantic will allow the study of any links between shifts in the Atlantic Ocean circulation and the rapid climate events detected over Greenland.
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Rana Arnold Fine (born April 1944) is Professor Emeritus from the University of Miami's Rosenstiel School of Marine and Atmospheric Science. Her research primarily addresses understanding ocean circulation processes over time through the use of chemical tracers and the connection to climate.
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Erin Christine Pettit (born 1971) is an American glaciologist focusing on climate change. She is an associate professor of geophysics and glaciology at the University of Alaska Fairbanks, Alaska. Her work focuses on ice shelf disintegration, sea-level rise and ocean circulation changes.
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The canyon is being studied as part of the EU HERMES project using a remotely operated vehicle. The project is investigating the specialised canyon ecosystems, sediment transport and deposition, and the way in which the canyon influences and is affected by local ocean circulation.
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In order to gain an idea of the effect that large freshwater fluxes into the ocean would have on global ocean circulation, numerical modeling is needed. Of particular importance to the cases of freshwater fluxes from Lake Agassiz are the locations of their entry into the ocean and the rapidity at which they entered. The likely outcome is that the fluxes themselves, combined with the effect of the re-direction of the Agassiz Baseline flow, had an appreciable impact on ocean circulation and consequently climate. Some simulations of North Atlantic Deep Water formation confirm that the oceans and the thermohaline circulation are affected by these fluxes.
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The Modular Ocean Model (MOM) is a three-dimensional ocean circulation model designed primarily for studying the ocean climate system. The model is developed and supported primarily by researchers at the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory (NOAA/GFDL) in Princeton, NJ, USA.
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Carl Wunsch was the Cecil and Ida Green Professor of Physical Oceanography at the Massachusetts Institute of Technology, until he retired in 2013. He is known for his early work in internal waves and more recently for research into the effects of ocean circulation on climate.
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This data is important to collect and analyze because it is a critical factor in understanding the changes in Earth's climate brought on by global warming as well as ocean circulation. NOAA's National Weather Service uses Jason-3's data to more accurately forecast tropical cyclones.
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Lastly, there were concerns involving the accuracy and reliability of some measurements. The WOCE was meant to address these problems by providing new data collected in ways designed to “meet the needs of global circulation models for climate prediction.” The World Ocean Circulation Experiment. J.D. Woods.
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ESA's Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) was launched on March 16, 2009. It used ion propulsion throughout its twenty-month mission to combat the air-drag it experienced in its low orbit (altitude of 255 kilometres) before intentionally deorbiting on November 11, 2013.
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Density-driven thermohaline circulation Energy for the ocean circulation (and for the atmospheric circulation) comes from solar radiation and gravitational energy from the sun and moon.Munk, W. and Wunsch, C., 1998: Abyssal recipes II: energetics of tidal and wind mixing. Deep-Sea Research Part I, 45, pp. 1977-- 2010.
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Climate change and the subsequent melting of the Southern ice sheet have slowed the formation of AABW, and this slowdown is likely to continue. A complete shutdown of AABW formation is possible as soon as 2050. This shutdown would have dramatic effects on ocean circulation and global weather patterns.
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Katharine Anne Giles (22 March 1978 - 8 April 2013) was a British climate scientist. Her research considered sea ice cover, ocean circulation and wind patterns. She was a passionate science communicator, and since 2015, the Association of British Science Writers has held a science blog award in her honour.
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Britannica Concise. 2008: Encyclopædia Britannica, Inc. The centers of both the Water Hemisphere and the Western Hemisphere are in the Pacific Ocean. Ocean circulation ( caused by the Coriolis effect ) subdivides it into two largely independent volumes of water, which meet at the equator: the North(ern) Pacific Ocean and South(ern) Pacific Ocean.
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K. Bryan, J. Comput. Phys. 4, 347 (1969) The first application with specified global geometry was done in the early 1970s.M. D. Cox, in Numerical Models of Ocean Circulation (National Academy of Sciences, Washington, DC, 1975), pp. 107 120 Cox designed a 2° latitude-longitude grid with up to 12 vertical levels at each point.
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Several causes have been proposed: cyclical lows in solar radiation, heightened volcanic activity, changes in the ocean circulation, variations in Earth's orbit and axial tilt (orbital forcing), inherent variability in global climate, and decreases in the human population (for example from the Black Death and the epidemics emerging in the Americas upon European contact).
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Other climate determinants are more dynamic: the thermohaline circulation of the ocean leads to a 5 °C (9 °F) warming of the northern Atlantic Ocean compared to other ocean basins.Stefan Rahmstorf The Thermohaline Ocean Circulation: A Brief Fact Sheet. Retrieved on 2008-05-02. Other ocean currents redistribute heat between land and water on a more regional scale.
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Joseph Pedlosky (born April 7, 1938) is an American physical oceanographer. He is a scientist emeritus at the Woods Hole Oceanography Institute. Pedlosky was elected to the United States National Academy of Sciences in 1985. He is the author of the textbooks Geophysical Fluid Dynamics, Ocean Circulation Theory, and Waves in the Ocean and Atmosphere: Introduction to Wave Dynamics.
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At the start of the PETM, the ocean circulation patterns changed radically in the course of under 5,000 years. Global-scale current directions reversed due to a shift in overturning from the southern hemisphere to northern hemisphere overturning. This "backwards" flow persisted for 40,000 years. Such a change would transport warm water to the deep oceans, enhancing further warming.
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Edmonds, Alan, Voyage to the Edge of the World, McClelland and Stewart, Toronto, 1973 In the eighties and nineties surveys within the framework of the international Joint Global Ocean Fluxes Study and World Ocean Circulation Experiment were completed by the Hudson. Other research projects included the 1983 Canadian Expedition to Study the Alpha Ridge (CESAR) off of Ellesmere Island.
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Ocean circulation and climate during the past 120,000 years. Nature, 419(6903):207 This is in contrast to more comprehensive models, which bias towards a stable AMOC characterised by a single equilibrium. However, doubt is cast upon this stability by a modelled northward freshwater flux which is at odds with observations.Drijfhout, Sybren S., Susanne L. Weber, and Eric van der Swaluw.
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Aquarius data was important to the Salinity Processes in the Upper Ocean Regional Study (SPURS), a year-long international field study of the oceanographic processes that sustain the maximum surface salinities in the central subtropical North Atlantic, and influence global ocean circulation. The Aquarius instrument successfully achieved its science objectives and completed its primary three-year mission in November 2014.
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International Geosphere-Biosphere Programme More completely, the term "global change" encompasses: population, climate, the economy, resource use, energy development, transport, communication, land use and land cover, urbanization, globalization, atmospheric circulation, ocean circulation, the carbon cycle, the nitrogen cycle, the water cycle and other cycles, sea ice loss, sea-level rise, food webs, biological diversity, pollution, health, over fishing, and more.
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The opening and closing of ocean gateways: the opening of the Drake Passage; the opening of the Tasmanian Gateway and the closing of the Tethys seaway; along with the final formation of the Greenland–Iceland–Faroes Ridge; played vital parts in reshaping oceanic currents during the Oligocene. As the continents shifted to a more modern configuration, so too did ocean circulation.
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Southern Greenland's margins and outlet glaciers are thinning at a dramatic rate, and this rate appears to be accelerating. These changes will have profound implications for global sea levels, ocean circulation, regional climate, and society. The acceleration in the rate of thinning represents more than simply melting, and coincides with major changes in the dynamics of outlet glaciers (e.g. Rignot & Kanagaratnam 2006).
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Meissner researches abrupt climate change events, and thresholds and feedbacks in the climate system using Earth System Climate Models together with palaeoclimate records to increase understanding of the basic mechanisms of climate variability and climate change, particularly in the context of terrestrial biogeochemical cycles and ocean circulation. The work of her and her team developed model studies on rapid climate changes in Australia.
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Sea levels drop due to the removal of large volumes of water above sea level in the icecaps. There is evidence that ocean circulation patterns are disrupted by glaciations. Since the earth has significant continental glaciation in the Arctic and Antarctic, we are currently in a glacial minimum of a glaciation. Such a period between glacial maxima is known as an interglacial.
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Craig discovered submarine Hydrothermal vents by measuring helium 3 and radon emitted from seafloor spreading centers. He made 17 dives to the bottom of the ocean in the ALVIN submersible, including the first descent into the Mariana Trough. There he discovered hydrothermal vents nearly 3700m deep. Craig proved that there was excess 3He instead of 4He, affecting the understanding for ocean circulation and seafloor spreading.
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This has resulted in the current strengthening and extending southward. This shift in the EAC flow past Tasmania is controlled the Southern Hemisphere subtropical ocean circulation. This trend is thought to be caused by changes in wind patterns due to ozone depletion over Australia. There is a strong consensus with climate models that this trend will continue to intensify and accelerate over the next 100 years.
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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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Instead ocean deep water is formed in polar regions where cold salty waters sink in fairly restricted areas. This is the beginning of the thermohaline circulation. Oceanic currents are largely driven by the surface wind stress; hence the large-scale atmospheric circulation is important to understanding the ocean circulation. The Hadley circulation leads to Easterly winds in the tropics and Westerlies in mid-latitudes.
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Jason-1 was a satellite altimeter oceanography mission. It sought to monitor global ocean circulation, study the ties between the ocean and the atmosphere, improve global climate forecasts and predictions, and monitor events such as El Niño and ocean eddies.. Jason-1 was launched in 2001 and it was followed by OSTM/Jason-2 in 2008, and Jason-3 in 2016 -- the Jason satellite series.
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Source: Llyod, J., Kuijpers, A., Long, A., Moros, M., and Park, L. 2007. Foraminiferal reconstruction of mid- to late Holocene ocean circulation and climate variability in Disko, Bugt, West Greenland. The Holocene: 17: 1079-1091. Paleoclimatology records derived from foraminifera abundance show that periodic influxes of warm subsurface temperatures and near-bottom temperatures occurred throughout the Late Holocene epoch, particularly during the Holocene climatic optimum.
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Management of the Earth's atmosphere involves assessment of all aspects of the carbon cycle to identify opportunities to address human-induced climate change and this has become a major focus of scientific research because of the potential catastrophic effects on biodiversity and human communities. Ocean circulation patterns have a strong influence on climate and weather and, in turn, the food supply of both humans and other organisms.
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In addition to supporting NURC's scientific mission, the two vessels are chartered to commercial or government organizations within the NATO nations. CMRE has specialized facilities and equipment for research at-sea, including a fleet of AUVs and other unmanned vehicles and instrumentation, linear array assembly facilities, and the Oceanography Calibrating Laboratory, which provides instrument calibration according to the World Ocean Circulation Experiment (WOCE) standard.
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Aquarius' mission was to demonstrate that accurate measurements of salinity could be made from space, and was the first spaceborne instrument to use both passive radiometers and active radar in the L band. By measuring ocean salinity, scientists are better able to understand the Earth's water cycle and ocean circulation. Project scientists later derived a method of pulling soil moisture data from Aquarius' radiometer.
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The generation of high salinity surface waters at low latitudes, which were therefore of higher density and thus sank, is thought to have been the dominant ocean circulation driver during greenhouse climates such as the Cretaceous. Similar dynamics operate today in the Mediterranean. The formation of bottom waters by halothermal dynamics is considered to be one to two orders of magnitude weaker than in thermohaline systems.
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A secondary variable is nutrient availability. Although large areas of the tropical and sub-tropical oceans have abundant light, they experience relatively low primary production because they offer limited nutrients such as nitrate, phosphate and silicate. This results from large-scale ocean circulation and water column stratification. In such regions, primary production usually occurs at greater depth, although at a reduced level (because of reduced light).
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Unaveraged or instantaneous sea surface height (SSH) is most obviously affected by the tidal forces of the Moon and the Sun acting on the Earth. Over longer timescales, SSH is influenced by ocean circulation. Typically, SSH anomalies resulting from these forces differ from the mean by less than ± at the global scale. Other influences include temperature, salinity, tides, waves, and the loading of atmospheric pressure.
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The satellites detect global sea level mean and record the fluctuations. Also detecting the slow change of upper ocean circulation on decadal time scales, every ten years. Studying the transportation of heat and carbon in the ocean and examining the main components that fuel deep water tides. The satellites data collection also helps improve wind speed and height measurements in current time and for long- term studies.
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Lisiecki's current research focuses on paleoclimatology. Lisiecki's research interest in paleoclimatology arose from the lack of research and current understanding of the glacial cycles. Lisiecki uses various computational and mathematical methods to interpret and compare different paleoclimate records. In specific, she focuses on the evolution of the Plio-Pleistocene climate due to its relation to the Milankovitch forcing, 100-kyr glacial cycles, the carbon cycle, and deep-ocean circulation.
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These expeditions sought to determine the effects of atmospheric pollution on global climate, and to understand the physics of climate change on Earth. Results from these cruises were used to improve global climate, ocean circulation, and greenhouse gas models. NOAA decommissioned Discoverer at Seattle, Washington, on 16 August 1996. She remained inactive in reserve in the NOAA Pacific Fleet at Seattle until she was scrapped at Aliağa, Turkey in 2010.
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Though much is understood about the interactions between large-scale paleoflooding, ocean circulation, and climate, there is still much to learn. Regarding the freshening episodes of the Champlain Sea, the exact locations and timing of drainage into the sea still remain in question. These factors, in turn, affected how ocean circulations, and potentially climate, changed. What is known of the drainage of Lake Agassiz is largely based on modeling studies.
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In the 14th century, the growing season in Europe became unreliable; meanwhile in China the cultivation of oranges was driven southward by colder temperatures. Especially in Europe, the Little Ice Age had great cultural ramifications. It persisted until the Industrial Revolution, long after the Post-classical Period. Its causes are unclear: possible explanations include sunspots, orbital cycles of the Earth, volcanic activity, ocean circulation, and man-made population decline.
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Because of conservation of potential vorticity caused by the poleward-moving winds on the subtropical ridge's western periphery and the increased relative vorticity of poleward moving water, transport is balanced by a narrow, accelerating poleward current, which flows along the western boundary of the ocean basin, outweighing the effects of friction with the cold western boundary current which originates from high latitudes.Angela Colling (2001). Ocean circulation. Butterworth-Heinemann, pp. 96.
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Coriolis and turbulent drag forces. In the picture above, the wind blowing North in the northern hemisphere creates a surface stress and a resulting Ekman spiral is found below it in the water column. Ekman transport is part of Ekman motion theory, first investigated in 1902 by Vagn Walfrid Ekman. Winds are the main source of energy for ocean circulation, and Ekman Transport is a component of wind-driven ocean current.
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Henry "Hank" Melson Stommel (September 27, 1920 – January 17, 1992) was a major contributor to the field of physical oceanography. Beginning in the 1940s, he advanced theories about global ocean circulation patterns and the behavior of the Gulf Stream that form the basis of physical oceanography today. Widely recognized as one of the most influential and productive oceanographers of his time, Stommel was both a groundbreaking theoretician and an astute, seagoing observer.
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Gravity gradiometry has predominately been used to image subsurface geology to aid hydrocarbon and mineral exploration. Over 2.5 million line km has now been surveyed using the technique. The surveys highlight gravity anomalies that can be related to geological features such as Salt diapirs, Fault systems, Reef structures, Kimberlite pipes, etc. Other applications include tunnel and bunker detection and the recent GOCE mission that aims to improve the knowledge of ocean circulation.
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Even the sill depth and location is largely unknown as modern soundings of the fjord, with its mouth located between Cape Morton and Cape Tyson, are still lacking.Johnson, H.L., A. Muenchow, K.K. Falkner, and H. Melling, 2010: Ocean Circulation and properties in Petermann Fjord, Greenland, Journal of Geophysical Research, . Petermann Glacier marks the western limit of Hall Land and the eastern of Daugaard-Jensen Land. The Petermann Peninsula flanks its northern end.
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Consider a scientific research group working on environmental observation and forecasting, such as the CORIE System1. They may be monitoring a coastal ecosystem through weather stations, shore- and buoy-mounted sensors and remote imagery. In addition they could be running atmospheric and fluid- dynamics models that simulate past, current and near future conditions. The computations may require importing data and model outputs from other groups, such as river flows and ocean circulation forecasts.
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A summary of the path of the thermohaline circulation. Blue paths represent deep-water currents, while red paths represent surface currents. Thermohaline circulation Thermohaline circulation (THC) is a part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes. The adjective thermohaline derives from thermo- referring to temperature and ' referring to salt content, factors which together determine the density of sea water.
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During photosynthesis, organisms using the C3 pathway show different enrichments compared to those using the C4 pathway, allowing scientists not only to distinguish organic matter from abiotic carbon, but also what type of photosynthetic pathway the organic matter was using. Occasional spikes in the global 13C/12C ratio have also been useful as stratigraphic markers for chemostratigraphy, especially during the Paleozoic. The 14C ratio has been used to track ocean circulation, among other things.
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The surface layer is studied in oceanography, as both the wind stress and action of surface waves can cause turbulent mixing necessary for the formation of a surface layer. The world's oceans are made up of many different water masses. Each have particular temperature and salinity characteristics as a result of the location in which they formed. Once formed at a particular source, a water mass will travel some distance via large-scale ocean circulation.
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Wåhlin is a Professor of Physical Oceanography at the Department of Marine Sciences, University of Gothenburg. Her research focus is in the field of Polar Oceanography, mostly in the Southern Ocean. Specifically her research investigates several aspects of dynamics of polar seas including physical oceanography, ocean circulation, topographic effects, ice shelf melt processes and air-sea-ice interaction. When Wåhlin was appointed professor in 2015 she became Sweden's first woman full Professor of Oceanography.
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An idealised view of three pairs of large circulation cells. Atmospheric circulation is the large-scale movement of air through the troposphere, and the means (with ocean circulation) by which heat is distributed around Earth. The large-scale structure of the atmospheric circulation varies from year to year, but the basic structure remains fairly constant because it is determined by Earth's rotation rate and the difference in solar radiation between the equator and poles.
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Crossing a threshold in one part of the climate system may trigger another tipping element to tip into a new state. These are so-called cascading tipping points. Ice loss in West Antarctica and Greenland will significantly alter ocean circulation. Sustained warming of the northern high latitudes as a result of this process could activate tipping elements in that region, such as permafrost degradation, loss of Arctic sea ice, and Boreal forest dieback.
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Cambridge University Press, 1994 Chlorobium species are thought to have played an important part in mass extinction events on Earth. If the oceans turn anoxic (due to the shutdown of ocean circulation) then Chlorobium would be able to out compete other photosynthetic life. They would produce huge quantities of methane and hydrogen sulfide which would cause global warming and acid rain. This would have huge consequences for other oceanic organisms and also for terrestrial organisms.
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It was likely related to warming elsewhere while some other regions were colder, such as the tropical Pacific. Average global mean temperatures have been calculated to be similar to early-mid-20th- century warming. Possible causes of the Medieval Warm Period include increased solar activity, decreased volcanic activity, and changes to ocean circulation. The period was followed by a cooler period in the North Atlantic and elsewhere termed the Little Ice Age.
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Susan Lozier is a physical oceanographer and the dean of the Georgia Institute of Technology's College of Sciences. Previously, she was the Ronie-Richelle Garcia-Johnson Professor of Earth and Ocean Sciences in the Nicholas School of the Environment at Duke University in Durham, North Carolina. Her research focuses on large-scale ocean circulation, the ocean's role in climate variability, and the transfer of heat and fresh water from one part of the ocean to another.
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The presence of an internal global salty ocean with an aquatic environment supported by global ocean circulation patterns, with an energy source and complex organic compounds in contact with Enceladus's rocky core, may advance the study of astrobiology and the study of potentially habitable environments for microbial extraterrestrial life.Habitability of Enceladus: Planetary Conditions for Life. (PDF) Christopher D. Parkinson, Mao-Chang Liang, Yuk L. Yung, and Joseph L. Kirschivnk. Origins of Life and Evolution of Biospheres April 10, 2008.
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Dickey used data collected by the GRACE Mission—which was unable to monitor Earth's gravity field with unprecedented accuracy—to better understand how factors like global warming, changing ocean circulation patterns, glacial ice melt, and changes to the composition of solid Earth affect the field of gravity. In one 2002 study, Dickey and her colleagues linked a tripling in the average rate of glacial ice melt to the flattening of the Earth and subsequent changes in its gravitational field.
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Ocean circulation patterns have a strong influence on climate and weather and, in turn, the food supply of both humans and other organisms. Scientists have warned of the possibility, under the influence of climate change, of a sudden alteration in circulation patterns of ocean currents that could drastically alter the climate in some regions of the globe. Ten per cent of the world's population—about 600 million people—live in low-lying areas vulnerable to sea-level rise.
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After his PhD, he joined the National Institute of Oceanography (NIO) in Wormley, and remained with this organisation and its successor institutesThese included: James Rennell Centre for Ocean Circulation, formed 1990; Southampton Oceanography Centre, formed 1995; National Oceanography Centre, Southampton, formed 2005. throughout his career. Here, together with NIO colleagues, Fasham developed one of the first shipborne computer systems. He also applied his experience in statistics to the biogeography of plankton, a field that was then largely descriptive.
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Sikuliaq allows up to 26 scientists and students to conduct multi-disciplinary studies in high latitude open seas, near-shore regions and single-year sea ice, and facilitates the real-time virtual participation of classroom students via broadband connections. The major research opportunities include the effect of climate change and increased human use of Arctic regions on various issues such as ocean circulation and ecosystem dynamics.History of the ARRV project. UAF School of Fisheries and Ocean Sciences.
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The position of the continents determines the geometry of the oceans and therefore influences patterns of ocean circulation. The locations of the seas are important in controlling the transfer of heat and moisture across the globe, and therefore, in determining global climate. Lastly, the biosphere also interacts with the rest of the climate system. Vegetation is often darker or lighter than the soil beneath, so that more or less of the Sun's heat gets trapped in areas with vegetation.
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Monsoons, seasonal changes in wind and precipitation that occur mostly in the tropics, form due to the fact that land masses heat up more easily than the ocean. The temperature difference induces a pressure difference between land and ocean, driving a steady wind. Ocean water that has more salt has a higher density and differences in density play an important role in ocean circulation. The thermohaline circulation transports heat from the tropics to the polar regions.
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There was abundant CO2 in the atmosphere which resulted in global warming. A theory was proposed that ocean circulation changed direction with two water masses in the Atlantic Ocean changing direction. One of the water masses sank to the ocean floor, took direction south, and ended up in the tropical Atlantic. The other water mass replaced the first water mass on the ocean surface around Greenland which warmed the Atlantic Ocean while the rest of the ocean cooled.
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Although Mariners have been aware of the existence of the Monsoon current for nearly one thousand years, a detailed understanding did not emerge until after the International Indian Ocean Expedition of the 1960s. The World Ocean Circulation Experiment of the mid 1990s permitted detailed measurement of these currents through an extensive field campaign.Schott, Friedrich A. and Julian P. McCreary, Jr., 2001: The monsoon circulation of the Indian Ocean, Progress In Oceanography, Volume 51, Issue 1, Pages 1–123.
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The Centre for Polar Observation & Modelling (CPOM) is a centre for research into polar region processes which may affect: polar atmosphere and ocean circulation; the Earth's albedo; and global sea levels. It is funded by the Natural Environment Research Council, a UK Research Council.CPOM Website CPOM comprises research groups from 3 Universities: University College London, University of Bristol, and University of Edinburgh. In 2006, research carried out by CPOM resulted in the press report "Secret rivers found in Antarctic".
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See Thermohaline Circulation. The term halothermal circulation refers to the part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and evaporation. The adjective halothermal derives from halo- referring to salt content and -thermal referring to temperature, factors which together determine the density of sea water. Halothermal circulation is driven primarily by salinity changes and secondarily by temperature changes (as opposed to the thermohaline mode in modern oceans).
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In 1948 Henry Stommel proposed a circulation for the entire ocean depth by starting with the same equations as Sverdrup but adding bottom friction, and showed that the variation in Coriolis parameter with latitude results in a narrow western boundary current in ocean basins. Walter Munk in 1950 combined the results of Rossby (eddy viscosity), Sverdrup (upper ocean wind driven flow) and Stommel (western boundary current flow) and proposed a complete solution for the ocean circulation.
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The Oligocene sees the beginnings of modern ocean circulation, with tectonic shifts causing the opening and closing of ocean gateways. Cooling of the oceans had already commenced by the Eocene/Oligocene boundary, and they continued to cool as the Oligocene progressed. The formation of permanent Antarctic ice sheets during the early Oligocene and possible glacial activity in the Arctic may have influenced this oceanic cooling, though the extent of this influence is still a matter of some significant dispute.
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Cold water is more dense than warm water and salty water is more dense than freshwater. This means the density of ocean water changes as its temperature and salinity changes. These changes in density are the main source of the power that drives the ocean circulation. Surface ocean salinity measurements taken since the 1950s indicate an intensification of the global water cycle with high saline areas becoming more saline and low saline areas becoming more less saline.
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Surface heat and freshwater fluxes create global density gradients that drive the thermohaline circulation part of large-scale ocean circulation. It plays an important role in supplying heat to the polar regions, and thus in sea ice regulation. Changes in the thermohaline circulation are thought to have significant impacts on Earth's energy budget. In so far as the thermohaline circulation governs the rate at which deep waters reach the surface, it may also significantly influence atmospheric carbon dioxide concentrations.
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23, no. 1, pp. 4–8.Fairbanks, R.G., 1989, A 17,000-year glacio- eustatic sea-level record: influence of glacial melting rates on the Younger Dryas event and deep ocean circulation. Nature. v. 342, no. 6250, pp. 637–642. As a result, the location from where Gifford and Ball collected the sample of limestone was between (295 and 312 feet) above sea level at the time indicated by the uranium-thorium date of 14,992±258 BP (7132-19/2).
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Climate change in the Arctic region is leading to widespread ecosystem restructuring. The distribution of species is changing along with the structure of food webs. Changes in ocean circulation appear responsible for the first exchanges of zooplankton between the North Pacific and North Atlantic regions in perhaps 800,000 years. These changes can allow the transmission of diseases from subarctic animals to Arctic ones, and vice versa, posing an additional threat to species already stressed by habitat loss and other impacts.
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In September 1933 and January 1935, Goldsbrough published two papers on steady ocean circulation that incorporated the variation of the Coriolis parameter with latitude. These two papers anticipated, to some extent, Rossby's 1939 planetary wave theory, Sverdrup's 1947 theory relating the curl of the wind stress to meridional transport, and Stommel's 1948 theory of the westward intensification of wind-driven ocean currents. Furthering some papers published in 1922,Goldsbrough, G. R. (1922). The Influence of Satellites upon the Form of Saturn's Ring.
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Further, they can distinguish between different land-based plants, depending on the type of photosynthesis they undergo. Therefore, the C/N ratio serves as a tool for understanding the sources of sedimentary organic matter, which can lead to information about the ecology, climate, and ocean circulation at different times in Earth’s history. C/N ratios in the range 4-10:1 are usually from marine sources, whereas higher ratios are likely to come from a terrestrial source.Gray KR, Biddlestone AJ. 1973.
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Earth's atmosphere and hydrosphere—Earth's heat engine—are coupled processes that constantly even out solar heating imbalances through evaporation of surface water, convection, rainfall, winds and ocean circulation, when distributing heat around the globe. A Hadley cell is an example of a heat engine. It involves the rising of warm and moist air in the earth's equatorial region and the descent of colder air in the subtropics creating a thermally driven direct circulation, with consequent net production of kinetic energy.
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When the WOCE was conceived, there were three main motivations for its creation. The first of these is the inadequate coverage of the World Ocean, specifically in the Southern Hemisphere. Data was also much more sparse during the winter months than the summer months, and there was—and still to some extent—a critical need for data covering all seasons. Secondly, the data that did exist was not initially collected for studying ocean circulation and was not well suited for model comparison.
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Carbon-to-iron ratios in phytoplankton are much larger than carbon-to-nitrogen or carbon-to-phosphorus ratios, so iron has the highest potential for sequestration per unit mass added. Oceanic carbon naturally cycles between the surface and the deep via two "pumps" of similar scale. The "solubility" pump is driven by ocean circulation and the solubility of CO2 in seawater. The "biological" pump is driven by phytoplankton and subsequent settling of detrital particles or dispersion of dissolved organic carbon.
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This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of around 1000 years)The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity; What is the global ocean conveyor belt? upwell in the North Pacific. Extensive mixing therefore takes place between the ocean basins, reducing differences between them and making the Earth's oceans a global system.
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Historically, there have been cyclical ice ages in which glacial sheets periodically covered the higher latitudes of the continents. Ice ages may occur because of changes in ocean circulation and continentality induced by plate tectonics. The Milankovitch theory predicts that glacial periods occur during ice ages because of astronomical factors in combination with climate feedback mechanisms. The primary astronomical drivers are a higher than normal orbital eccentricity, a low axial tilt (or obliquity), and the alignment of summer solstice with the aphelion.
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Toxic metals on the ocean floor may have dissolved into the water when the oceans' oxygen was depleted. An increase in available nutrients in the oceans may have been a factor, and decreased ocean circulation caused by global cooling may also have been a factor. The toxic metals may have killed life forms in lower trophic levels of the food chain, causing a decline in population, and subsequently resulting in starvation for the dependent higher feeding life forms in the chain.
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Ocean salinity is a measure of how much dissolved salt is in the ocean. The salts come from erosion and transport of dissolved salts from the land. The surface salinity of the ocean is a key variable in the climate system when studying the global water cycle, ocean–atmosphere exchanges and ocean circulation, all vital components transporting heat, momentum, carbon and nutrients around the world.New maps of salinity reveal the impact of climate variability on oceans European Space Agency, 2 December 2019, PHYS.ORG.
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The five major ocean gyres. In 1948, Munk took a year's sabbatical to visit Sverdrup in Oslo, Norway on his first Guggenheim Fellowship. He worked on the problem of wind-driven ocean circulation, obtaining the first comprehensive solution for currents based on observed wind patterns. This included two types of friction: horizontal friction between water masses moving at different velocities or between water and the edges of the oceanic basin, and friction from a vertical velocity gradient in the top layer of the ocean (the Ekman layer).
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Minze Stuiver is a geochemist who was at the forefront of geoscience research from the 1960s until his retirement in 1998. He helped transform radiocarbon dating from a simple tool for archaeology and geology to a precise technique with applications in solar physics, oceanography, geochemistry, and carbon dynamics. Minze Stuiver’s research encompassed the use of radiocarbon (14C) to understand solar cycles and radiocarbon production, ocean circulation, lake carbon dynamics and archaeology as well as the use of stable isotopes to document past climate changes.
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A closed seaway would have led to a very different North Atlantic Ocean circulation, impacting the surrounding atmospheric temperatures, which in turn affected the glacial cycle. The emergence of the isthmus caused a reflection of the westward-flowing North Equatorial Current northward and enhanced the northward-flowing Gulf Stream. The Pacific coast of South America would have cooled as the input of warm water from the Caribbean was cut off. This trend is thought to have caused the extinction of the marine sloths of the area.
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Drifting buoys have exposed a southward drift of sea ice toward Ellesmere Island and Nares Strait. It has been concluded that shear in the Lincoln Sea narrow boundary current plays an important role in shifting and thus removing sea ice from the Arctic region. The majority of sea ice export takes place on the eastern edges of the Arctic Ocean circulation near Greenland through the Fram Strait. Sea ice export through the Canadian archipelago was originally assumed to be zero, but that is not the case.
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As these surfaces flip from reflecting a lot of light to being dark after the ice has melted, they start absorbing more heat. The Southern Hemisphere already had little sea ice in summer before it started warming.. Arctic temperatures have increased and are predicted to continue to increase during this century at over twice the rate of the rest of the world.; . Melting of glaciers and ice sheets in the Arctic disrupts ocean circulation, including a weakened Gulf Stream, causing increased warming in some areas..
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It was truly a pioneering effort to determine how accurately we could measure ocean salinity from space and for the first time study large and small-scale interactions of the global water cycle.” Aquarius principal investigator Gary Lagerloef of Earth & Space Research, Seattle. Aquarius provided information into the natural exchange of freshwater between the ocean, atmosphere and sea ice, which influences ocean circulation, weather and climate. Data from Aquarius showed how extreme floods affect the seas and how low-salinity river plumes affect hurricane intensity.
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Arctic and Antarctic sea ice concentration climatology from 1981-2010, at the approximate seasonal maximum and minimum levels based on passive microwave satellite data. Brine rejection occurs in the sea ice packs around at the north and south poles of the earth [Fig. 3]. The Arctic Ocean has historically ranged from roughly 14-16 million square kilometers in late winter to roughly 7 million square kilometers each September. The annual increase of ice plays a major role in the movement of ocean circulation and deep water formation.
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All isotopes of a chemical element contain the same number of protons with varying numbers of neutrons. The element hydrogen has three naturally occurring isotopes, H, H and H, which are sometimes referred to as protium (H), deuterium (D) and tritium (T), respectively. Both H and H are stable indefinitely, while H is unstable and undergoes beta decay to form He. While there are some important applications of H in geochemistry (such as its use as an ocean circulation tracer) these will not be discussed further here.
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North Pacific Current splitting into southward California Current and northward Alaska Current (bifurcation in image occurring around 45°N). Haida eddies occur within the subpolar Alaska Gyre to the north of the Pacific Current. Arrows indicate the direction of the current. Ocean circulation in the region begins with the transport of waters eastward along the North Pacific Current, also known as the "West Wind Drift", which forms the northern branch of the anticyclonic (clockwise rotation of fluids in Northern Hemisphere) North Pacific subtropical gyre.
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The slowest and largest variations are due to changes in the Earth's gravitational field (geoid) due to the rearrangement of continents, formation of sea mounts and other redistribution of rock. Since the Earth's gravitational field is relatively stable on decadal to centennial timescales, ocean circulation plays a more significant role in the observed variation of SSH. Across the seasonal cycle changes in patterns of warming, cooling and surface wind forcing affect circulation and influence SSH. Variations in SSH can be measured by satellite altimetry (e.g.
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Global ocean heat content from 1955–2019 Global warming is projected to have a number of effects on the oceans. Ongoing effects include rising sea levels due to thermal expansion and melting of glaciers and ice sheets, and warming of the ocean surface, leading to increased temperature stratification. Other possible effects include large-scale changes in ocean circulation. The oceans also serve as a sink for carbon dioxide, taking up much that would otherwise remain in the atmosphere, but increased levels of have led to ocean acidification.
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David Marshall (born 13 July 1968) is Professor of Physical Oceanography at the University of Oxford and a Fellow of St Hugh's College, Oxford. He was head of the sub-department of Atmospheric, Oceanic and Planetary Physics from 2014-2018. From 2008 to 2012 he was co-director of the 21st Century Ocean Institute within the Oxford Martin School. He was awarded the 2014 Appleton Medal and Prize by the Institute of Physics for "fundamental contributions to understanding the fluid dynamics of the global ocean circulation".
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In fluid dynamics, the Coriolis–Stokes force is a forcing of the mean flow in a rotating fluid due to interaction of the Coriolis effect and wave-induced Stokes drift. This force acts on water independently of the wind stress. This force is named after Gaspard-Gustave Coriolis and George Gabriel Stokes, two nineteenth-century scientists. Important initial studies into the effects of the Earth's rotation on the wave motion – and the resulting forcing effects on the mean ocean circulation – were done by , and .
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Depths in between, however, have higher rates of oxygen consumption and lower rates of advective supply of oxygen-rich waters. In much of the ocean, mixing processes enable the resupply of oxygen to these waters (i.e. waters that are part of the wind- driven subtropical gyre circulations are rapidly exchanged with the surface and never acquire a strong oxygen deficit). The distribution of the open-ocean oxygen minimum zones is controlled by the large-scale ocean circulation as well as local physical as well as biological processes.
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FVCOM simulation of hypersaline sea surface release and propagation under tidal conditions in the northern North Sea The Finite Volume Community Ocean Model (FVCOM; Formerly Finite Volume Coastal Ocean Model) is a prognostic, unstructured-grid, free-surface, 3-D primitive equation coastal ocean circulation model. The model is developed primarily by researchers at the University of Massachusetts Dartmouth and Woods Hole Oceanographic Institution, and used by researchers worldwide. Originally developed for the estuarine flooding/drying process, FVCOM has been upgraded to the spherical coordinate system for basin and global applications.
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Experiments illustrating rigidity produced by centrifugal force. Proceedings of the Royal Society of Edinburgh (1875–1876) 9(94):73–78. # Aitken, J. 1876. Experiments illustrating rigidity produced by centrifugal force. Proceedings of the Royal Philosophical Society of Glasgow (1875–1876) 10(1):99–106. # Aitken, J. 1878. Experiments illustrating rigidity produced by centrifugal force. The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, Fifth series, 5(29):81–105. # Aitken, J. 1876–77. On ocean circulation. Proceedings of the Royal Society of Edinburgh (1876–1877) 9(98):394–400. # Aitken, J. 1880.
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Scientific experiments involving drift objects—more generally called determinate drifters—provide information about currents and help researchers develop ocean circulation maps. For example, experiments conducted in the mid-1700s by Benjamin Franklin and others indicated the existence and approximate location of the Gulf Stream, with scientific confirmation following in the mid-1800s. Using a network of beachcomber informants, rear admiral Alexander Becher is believed to be the first (from 1808-1852) to study travel of so-called "bottle papers" around an ocean gyre (a large circulating current system).
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Therefore, ocean circulation, ocean temperature, and the temperature of the earth are all attributing to the movement of the tropical rain belt. It is evident that the trend is northward and the belt is currently situated in the northern tropics, but the possibility of southward movement does exist. The northward movement does affect many countries and crops because the tropical rain belt is essential to food production in areas that rely on heavy precipitation. The tropical regions will be affected most by the northward movement of the rain.
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The Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) was the first of ESA's Living Planet Programme satellites intended to map in unprecedented detail the Earth's gravity field. The spacecraft's primary instrumentation was a highly sensitive gravity gradiometer consisting of three pairs of accelerometers which measured gravitational gradients along three orthogonal axes. Launched on 17 March 2009, GOCE mapped the deep structure of the Earth's mantle and probed hazardous volcanic regions. It brought new insight into ocean behaviour; this in particular, was a major driver for the mission.
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Hurricane Forecasting: Altimeter data and satellite ocean wind data are incorporated into atmospheric models for hurricane season forecasting and individual storm severity. Ship Routing: Maps of ocean currents, eddies, and vector winds are used in commercial shipping and recreational yachting to optimize routes. Offshore Industries: Cable-laying vessels and offshore oil operations require accurate knowledge of ocean circulation patterns to minimize impacts from strong currents. Marine Mammal Research: Sperm whales, fur seals, and other marine mammals can be tracked, and therefore studied, around ocean eddies where nutrients and plankton are abundant.
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Columbia was a supercomputer built by Silicon Graphics (SGI) for the National Aeornautics and Space Administration (NASA), installed in 2004 at the NASA Advanced Supercomputing (NAS) facility located at Moffett Field in California. Named in honor of the crew who died in the Space Shuttle Columbia disaster, it increased NASA's supercomputing capacity ten-fold for the agency's science, aeronautics and exploration programs. Missions run on Columbia include high- fidelity simulations of the Space Shuttle vehicle and launch systems, hurricane track prediction, global ocean circulation, and the physics of supernova detonations.
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Wind-driven surface currents (such as the Gulf Stream) travel polewards from the equatorial Atlantic Ocean, cooling en route, and eventually sinking at high latitudes (forming North Atlantic Deep Water). This dense water then flows into the ocean basins. While the bulk of it upwells in the Southern Ocean, the oldest waters (with a transit time of about 1000 years)The global ocean conveyor belt is a constantly moving system of deep-ocean circulation driven by temperature and salinity; What is the global ocean conveyor belt? upwell in the North Pacific.
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This is also known as 'haline forcing' (net high latitude freshwater gain and low latitude evaporation). This warmer, fresher water from the Pacific flows up through the South Atlantic to Greenland, where it cools off and undergoes evaporative cooling and sinks to the ocean floor, providing a continuous thermohaline circulation.United Nations Environment Programme / GRID-Arendal, 2006, . Potential Impact of Climate Change Hence, a recent and popular name for the thermohaline circulation, emphasizing the vertical nature and pole-to-pole character of this kind of ocean circulation, is the meridional overturning circulation.
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The phenomenon of paleoflooding is apparent in the geologic record over various spatial and temporal scales. It often occurred on a large scale, and was the result of either glacial ice melt causing large outbursts of freshwater, or high sea levels breaching bodies of freshwater. If a freshwater outflow event was large enough that the water reached the ocean system, it caused changes in salinity that potentially affected ocean circulation and global climate. Freshwater flows could also accumulate to form continental glacial lakes, and this is another indicator of large-scale flooding.
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Before a determination of the effects of freshwater fluxes from Lake Agassiz on global ocean circulation and climate can be made, it is important to establish its baseline flux value. This is essentially a natural background flux of water from the lake. From 21.4 – 9.5 ka calendar years, this baseline flux for Lake Agassiz has been found to be about 0.3 to 0.4 Sverdrup, or Sv, in total (1 Sv = 1 x 106 m3 s−1). This value was calculated using hydrological numerical model simulations and accounts for melt water and precipitation runoff.
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10 Nov. 2012. Oxygen isotopes across the K–T boundary suggest that oceanic temperatures fluctuated in the Late Cretaceous and through the boundary itself. Carbon isotope measurements of benthic foramifinera at the K–T boundary suggest rapid, repeated fluctuations in oceanic productivity in the 3 million years before the final extinction, and that productivity and ocean circulation ended abruptly for at least tens of thousands of years just after the boundary, indicating devastation of terrestrial and marine ecosystems. Some researchers suggest that climate change is the main connection between the impact and the extinction.
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An example of an effect on the troposphere is the change in speed of the Atlantic Ocean circulation pattern. A soft spot just south of Greenland is where the initial step of downwelling occurs, nicknamed the "Achilles Heel of the North Atlantic". Small amounts of heating or cooling traveling from the polar vortex can trigger or delay downwelling, altering the Gulf Stream Current of the Atlantic, and the speed of other ocean currents. Since all other oceans depend on the Atlantic Ocean's movement of heat energy, climates across the planet can be dramatically affected.
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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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Deep ocean currents are currently being researched using a fleet of underwater robots called Argo. The thermohaline circulation is a part of the large-scale ocean circulation that is driven by global density gradients created by surface heat and freshwater fluxes. The adjective thermohaline derives from thermo- referring to temperature and ' referring to salt content, factors which together determine the density of sea water. Wind-driven surface currents (such as the Gulf Stream) travel polewards from the equatorial Atlantic Ocean, cooling en route, and eventually sinking at high latitudes (forming North Atlantic Deep Water).
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Tropical regions (between the Tropic of Cancer and the Equator, 0° latitude) are generally hot all year round and tend to experience a rainy season during the summer months, and a dry season during the winter months. In the Northern Hemisphere, objects moving across or above the surface of the Earth tend to turn to the right because of the Coriolis effect. As a result, large-scale horizontal flows of air or water tend to form clockwise-turning gyres. These are best seen in ocean circulation patterns in the North Atlantic and North Pacific oceans.
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The planned global study sites include instrumented moorings and gliders in four locations: Argentine Basin; Irminger Sea; Southern Ocean; and Station Papa.Station Papa The global arrays are developed and operated by Woods Hole and Scripps. Observations from these high latitude areas are critical to understanding ocean circulation and climate change processes. The global arrays each include four moorings (except Station Papa, which has three) composed of fixed and moving sensors that measure air-sea fluxes of heat, moisture, and momentum—as well as physical, biological, and chemical properties of the water column.
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Although this is now thought unlikely in the near future, it has also been suggested that there could be a shutdown of thermohaline circulation, similar to that which is believed to have driven the Younger Dryas, an abrupt climate change event. There is also potentially a possibility of a more general disruption of ocean circulation, which may lead to an ocean anoxic event; these are believed to be much more common in the distant past. It is unclear whether the appropriate pre-conditions for such an event exist today.
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During 33 expeditions with the research vessel E. W. Scripps between 1938 and 1941 he produced a detailed oceanographic dataset off the coast of California. He also developed a simple theory of the general ocean circulation postulating a dynamical vorticity balance between the wind-stress curl and the meridional gradient of the Coriolis parameter, the Sverdrup balance. This balance describes wind-driven ocean gyres away from continental margins at western boundaries. After leaving Scripps, he became director of the Norwegian Polar Institute in Oslo and continued to contribute to oceanography, ocean biology and polar research.
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Thus, using CFCs in concert with SF6 as a tracer resolves the water dating issues due to decreased CFC concentrations. Using CFCs or SF6 as a tracer of ocean circulation allows for the derivation of rates for ocean processes due to the time-dependent source function. The elapsed time since a subsurface water mass was last in contact with the atmosphere is the tracer-derived age. Estimates of age can be derived based on the partial pressure of an individual compound and the ratio of the partial pressure of CFCs to each other (or SF6).
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De Menocal uses geochemical analyses of marine sediments to investigate past changes in ocean circulation and terrestrial climates. His goal is to understand how and why past climates have changed, with a specific interest in placing contemporary climate change trends within the context of climate changes during the prehistoric past. He has participated in 12 oceanographic research cruises and, in 2001, was on one of the last research cruises off the coast of northwest Africa before the region was declared off limits to scientists due to the threat posed by pirates.
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Oceans take up 15 – 40% of anthropogenic CO2, and so far roughly 40% of the carbon from fossil fuel combustion has been taken up into the oceans. Because the Revelle factor increases with increasing CO2, a smaller fraction of the anthropogenic flux will be taken up by the ocean in the future. Current annual increase in atmospheric CO2 is approximately 4 gigatons of carbon. This induces climate change that drives carbon concentration and carbon-climate feedback processes that modifies ocean circulation and the physical and chemical properties of seawater, which alters CO2 uptake.
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Earth's gravitational field is affected by changes in the masses of the ocean, the Greenland and Antarctic ice sheets, and the water stored in the continents. As water cycles among these areas, Earth's gravity fluctuates. Beginning in 1998, satellite data began to show an increasing oblateness—or flattening from a sphere to a non-spherical ellipsoid, widening the planet's diameter—in Earth's gravity field. Dickey and her colleagues sought to understand why exactly this was happening, turning their focus specifically on changes in ocean circulation, measurements of sea-surface height, and changes to sub-polar and mountain glaciers.
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SARAL or Satellite with ARgos and ALtiKa is a cooperative altimetry technology mission of Indian Space Research Organisation (ISRO) and CNES (Space Agency of France). SARAL performs altimetric measurements designed to study ocean circulation and sea surface elevation. The payloads of SARAL are The ISRO built satellite with payloads modules (ALTIKA altimeter), DORIS, Laser Retro- reflector Array (LRA) and ARGOS-3 (Advanced Research and Global Observation Satellite) data collection system provided by CNES was launched by Indian Polar Satellite Launch Vehicle rocket into the Sun-synchronous orbit (SSO). ISRO is responsible for the platform, launch, and operations of the spacecraft.
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The Dungeness crab is named after Dungeness, Washington, which is located approximately north of Sequim and east of Port Angeles. Its typical range extends from Alaska's Aleutian Islands to Point Conception, near Santa Barbara, California, while it is occasionally found as far south as Magdalena Bay, Baja California Sur, Mexico. A genetic analysis of adult Dungeness crabs indicated that there is one population across the California Current System, but it is likely that interannual variation in physical oceanographic conditions (such as ocean circulation patterns) influence larval recruitment among regions, causing genetic diversity to change through time.
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Woods has served on a number of international project committees, including GARP (Global Atmospheric Research Programme), WCRP (World Climate Research Programme0, IGBP (International GeoSphere-Biosphere Programme), EuroGOOS (European Global Ocean Observing System). He was co-chairman of the World Ocean Circulation Experiment. He was a lead author of the first report of the Intergovernmental Panel on Climate Change (IPCC), an organisation which was later awarded the 2007 Nobel Peace Prize jointly with Al Gore. He is now (2015) Emeritus Professor of Oceanography & Complex Systems in the Faculty of Engineering, Department of Earth Science & Engineering, Imperial College London.
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NewScientist, 30 November 2005 Following media discussions, Detlef Quadfasel pointed out that the uncertainty of the estimates of Bryden et al. is high, but says other factors and observations do support their results, and implications based on palaeoclimate records show drops of air temperature up to 10 °C within decades, linked to abrupt switches of ocean circulation when a certain threshold is reached. He concluded that further observations and modelling are crucial for providing early warning of a possible devastating breakdown of the circulation. In response Quirin Schiermeier concluded that natural variation was the culprit for the observations but highlighted possible implications.
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The research area Greenhouse Oceans (A) focused on the causes and effects of climate change in regards to the modern ocean. Interactions between the atmosphere, ocean surface, deep water regions and its organisms were closely studied. It was divided into seven research teams. Their members mostly focused on environmental research ranging from topics such as ocean acidification and its impact on marine life to global warming and its influence on the ocean floor to ocean circulation regarding climate modelling and even ocean surface chemistry, studying the exchange of gases between the water column and the atmosphere.
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Several proxy methods have been used to infer past ocean circulation and changes to it. They include carbon isotope ratios, cadmium/calcium (Cd/Ca) ratios, protactinium/thorium isotopes (231Pa and 230Th), radiocarbon activity (δ14C), neodymium isotopes (143Nd and 144Nd), and sortable silt (fraction of deep-sea sediment between 10 and 63 μm). Carbon isotope and cadmium/calcium ratio proxies are used because variability in their ratios is due partly to changes in bottom-water chemistry, which is in turn related the source of deep-water formation. These ratios, however, are influenced by biological, ecological, and geochemical processes which complicate circulation inferences.
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Recent satellite missions, such as the Gravity Field and Steady- State Ocean Circulation Explorer (GOCE) and GRACE, have enabled the study of time-variable geoid signals. The first products based on GOCE satellite data became available online in June 2010, through the European Space Agency (ESA)’s Earth observation user services tools. ESA launched the satellite in March 2009 on a mission to map Earth's gravity with unprecedented accuracy and spatial resolution. On 31 March 2011, the new geoid model was unveiled at the Fourth International GOCE User Workshop hosted at the Technische Universität München in Munich, Germany.
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December 1997 chart of ocean surface temperature anomaly [°C] during the last strong El Niño The interaction of ocean circulation, which serves as a type of heat pump, and biological effects such as the concentration of carbon dioxide can result in global climate changes on a time scale of decades. Known climate oscillations resulting from these interactions, include the Pacific decadal oscillation, North Atlantic oscillation, and Arctic oscillation. The oceanic process of thermohaline circulation is a significant component of heat redistribution across the globe, and changes in this circulation can have major impacts upon the climate.
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The ship was sold to Chile for operation by the Chilean Navy, renamed Vidal Gormaz for the founder of the Chilean Hydrographic Office, Commodore Francisco Vidal Gormaz (1837 - 1907), and commissioned at San Diego, California on 28 September 1992. x arrived at Valparaíso on 3 December 1992. The vessel participated in such research operations as Tropical Ocean Global Atmosphere, World Ocean Circulation Experiment, El Niño–Southern Oscillation and national Marine Scientific Research Voyages in National Fiords and Oceanic Islands and other Chilean scientific data collection. The ship, designated AGOR-60, was decommissioned by the Chilean Navy on 30 August 2010.
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During the June–July months, the mean seasonal cycle of freshwater content peaks; in this season, sea ice thickness reaches a minimum, implying that the amount of melted sea ice has reached a maximum. The maximum in freshwater content released into the ocean waters coincides with a maximum in wind stress curl (i.e., a minimum in Ekman pumping), allowing for a high volume of freshwater to seep into the Arctic Ocean circulation. This rapid influx of freshwater into the Arctic circulation forces a large volume of freshwater to outflow into the North Atlantic basin, affecting the Atlantic Meridional Overturning Circulation.
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The ACC carries up to 150 Sverdrups (150 million cubic meters per second), equivalent to 150 times the volume of water flowing in all the world's rivers. The ACC and the global thermohaline circulation strongly influence regional and global climate as well as underwater biodiversity. Another factor that contributes to the climate of the subantarctic region, though to a much lesser extent than the thermohaline circulation, is the formation of Antarctic Bottom Water (ABW) by halothermal dynamics. The halothermal circulation is that portion of the global ocean circulation that is driven by global density gradients created by surface heat and evaporation.
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TOPEX/Poseidon and Jason-1 have led to major advances in the science of physical oceanography and in climate studies. Their 15-year data record of ocean surface topography has provided the first opportunity to observe and understand the global change of ocean circulation and sea level. The results have improved the understanding of the role of the ocean in climate change and improved weather and climate predictions. Data from these missions are used to improve ocean models, forecast hurricane intensity, and identify and track large ocean/atmosphere phenomena such as El Niño and La Niña.
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Scientists have also detailed improved methods for using GRACE data to describe Earth's gravity field. GRACE data are critical in helping to determine the cause of sea level rise, whether it is the result of mass being added to the ocean - from melting glaciers, for example - or from thermal expansion of warming water or changes in salinity. High-resolution static gravity fields estimated from GRACE data have helped improve the understanding of global ocean circulation. The hills and valleys in the ocean's surface (ocean surface topography) are due to currents and variations in Earth's gravity field.
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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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Swarm is a European Space Agency (ESA) mission to study the Earth's magnetic field. High-precision and high-resolution measurements of the strength, direction and variations of the Earth's magnetic field, complemented by precise navigation, accelerometer and electric field measurements, will provide data for modelling the geomagnetic field and its interaction with other physical aspects of the Earth system. The results offer a view of the inside of the Earth from space, enabling the composition and processes of the interior to be studied in detail and increase our knowledge of atmospheric processes and ocean circulation patterns that affect climate and weather.
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The 1990 IPCC First Assessment Report estimated that equilibrium climate sensitivity to a doubling of lay between , with a "best guess in the light of current knowledge" of .Climate Change: The IPCC Scientific Assessment (1990), Report prepared for Intergovernmental Panel on Climate Change by Working Group I, Houghton JT, Jenkins GJ, Ephraums JJ (eds.), chapter 5, Equilibrium Climate Change — and its Implications for the Future , pp. 138–139 This report used models with simplified representations of ocean dynamics. The IPCC supplementary report, 1992, which used full-ocean circulation models, saw "no compelling reason to warrant changing" the 1990 estimate;IPCC '92 p.
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More generally, SWOT will help improve our knowledge of Earth's water cycle and ocean circulation, enhance our observation capacity by collecting unique data on water storage and fluxes and making them freely available, and help us better understand the physics that drives surface water and ocean dynamics. Water resources, natural risks (floods, climate change, hurricane forecasting, etc.), biodiversity, health (preventing the propagation of water-borne diseases), the agricultural sector, energy (including the management of electricity production and offshore gas and oil rigs), territorial development; all these areas and more stand to benefit from this new satellite mission.
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Her research and international/national committee work include a focus on ocean climate variability/change. She has played a leadership role in scientific planning and execution of international programs, including the World Ocean Circulation Experiment (WOCE) of the 1990s and the CLIVAR/CO2 Repeat Hydrography Program of the 2000s to present. In 2000, Talley and co-principal investigator, Daniel Rudnick, worked with moorings and hydrography on the collaborative Okhotsk Sea dense water formation project. In 2005-2006, Talley spent time in the field using hydrography, CTD, and profiling floats to understand Antarctic Intermediate Water formation in the southeast Pacific.
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In 1985 Jansen was hired as tenured associate professor at the University of Bergen, and he was in 1993 promoted to full professor. Jansen has published about 200 scientific papers on the relationship between ocean circulation and climate change with emphasis on the build-up and demise of ice sheets. Most of his studies are from the Arctic and sub-Arctic regions, but his work also encompasses oceans in the Southern Hemisphere and the tropics. His work combines geochemical and sedimentological methods on ocean sediments acquired through active participation the Ocean Drilling Program, the Images program and many cruises on Norwegian vessels.
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The barrier layer thickness (BLT) is a layer of water separating the well- mixed surface layer from the thermocline.Sprintall, J., and M. Tomczak, Evidence of the barrier layer in the surface-layer of the tropics, Journal of Geophysical Research: Oceans, 97 (C5), 7305-7316, 1992. A more precise definition would be the difference between mixed layer depth (MLD) calculated from temperature minus the mixed layer depth calculated using density. The first reference to this difference as the barrier layer was in a paper describing observations in the western Pacific as part of the Western Equatorial Pacific Ocean Circulation Study.
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Sandström's key (though not clearly expressed) insight, was that in such circulations, the circulation as a whole must transport light water downwards and dense water upwards. This means that the effect of the circulation is to increase the potential energy. Such an increase requires an external source of energy. Recent work has built on this to argue that the ocean circulation as a whole is driven by these external sources of energy, whether wind or tides, with newer work suggesting that internal sources and sinks of energy (such as those driving diffusion) are also potentially important.
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The five major ocean gyres In oceanography, a gyre () is any large system of circulating ocean currents, particularly those involved with large wind movements. Gyres are caused by the Coriolis effect; planetary vorticity, horizontal friction and vertical friction determine the circulatory patterns from the wind stress curl (torque).Heinemann, B. and the Open University (1998) Ocean circulation, Oxford University Press: Page 98 Gyre can refer to any type of vortex in an atmosphere or a sea, even one that is man-made, but it is most commonly used in terrestrial oceanography to refer to the major ocean systems.
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Duplessy led numerous oceanographic campaigns and showed that variations in the isotopic composition of fossil foraminifera present in the sediments of the various oceans made it possible to reconstruct changes in the isotopic composition of the ocean and ocean circulation on a large scale, which opened a new scientific field, paleo-oceanography.Duplessy J.C., et al., « Differential isotopic fractionation in benthic foraminifera and paleotemperatures reassessed », Science, 1970, 168, p. 250-251 This has grown to the point where there is now an international journal devoted to this discipline, of which he was one of the first associate editors.
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The surface currents flow in a clockwise direction in the Northern Hemisphere and anticlockwise in the Southern Hemisphere. The water moving away from the equator is warm, and that flowing in the reverse direction has lost most of its heat. These currents tend to moderate the Earth's climate, cooling the equatorial region and warming regions at higher latitudes. Global climate and weather forecasts are powerfully affected by the world ocean, so global climate modelling makes use of ocean circulation models as well as models of other major components such as the atmosphere, land surfaces, aerosols and sea ice.
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The Global Ocean Data Analysis Project (GLODAP) is a synthesis project bringing together oceanographic data, featuring two major releases as of 2018. The central goal of GLODAP is to generate a global climatology of the World Ocean's carbon cycle for use in studies of both its natural and anthropogenically-forced states. GLODAP is funded by the National Oceanic and Atmospheric Administration, the U.S. Department of Energy, and the National Science Foundation. The first GLODAP release (v1.1) was produced from data collected during the 1990s by research cruises on the World Ocean Circulation Experiment, Joint Global Ocean Flux Study and Ocean-Atmosphere Exchange Study programmes.
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During surveys of Canada's Arctic, Hudson employed a helicopter for the first time. During the early 1970s, Hudson performed surveys of the Bay of Fundy and Gulf of Maine. In March 1976, Hudson rescued the entire crew of the fishery patrol vessel Cape Freels, which had been abandoned on the Grand Banks of Newfoundland after catching fire. In the late 1970s, Hudson carried out the first survey of Baffin Bay. Hudson searching for debris from Swissair Flight 111 in foreground In the 1980s and 1990s, Hudson took part in large surveys that were part of international programs such as the Joint Global Ocean Fluxes Study and World Ocean Circulation Experiment.
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The two major advantages of ADCPs is the absence of moving parts that are subject to biofouling and the remote sensing aspect, where a single, stationary instrument can measure the current profile over ranges exceeding 1000 m. These features allow for long term measurements of the ocean currents over a significant portion of the water column. Since the start in the mid-1980s, many thousand ADCPs have been used in the world oceans and the instrument has played a significant role in our understanding of the world ocean circulation. The main disadvantage of the ADCPs is the loss of data close to the boundary.
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A surface nepheloid layer (SNL) may be created, due to particle flotation, while intermediate nepheloid layers (INL) may be formed at the slopes of the ocean bed due to the dynamics of internal waves. These intermediate nepheloid layers are derived from bottom nepheloid layers (BNL) after the layers become detached and spread along isopycnal surfaces. Deep ocean convection has a prominent effect on the distribution of nepheloid layers and their ability to form in certain areas of the ocean, such as the northern Atlantic Ocean and the northwestern Mediterranean Sea. Nepheloid layers are more likely to form based on patterns of deep ocean circulation that directly affect the abyssal plain.
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The combination of these forces produced the Isthmus of Panama and resulted in different sea surface salinity between the Pacific and Atlantic since 4.2 million years ago. It also resulted in massive interchange of species between North and South America and brought global changes in climate and ocean circulation. The Bocas del Toro Archipelago on the western Caribbean coast records local stratigraphy through this period, with Pliocene to Pleistocene coral reef carbonates overlying Miocene basalt and siliclastic shale. In the remote southeastern Darién Province, crystalline basement rock of the San Blas Complex forms massifs in the northeast and southwest, dating to the Cretaceous, Paleocene and Eocene.
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A recent example of tectonic control on ocean circulation is the formation of the Isthmus of Panama about 5 million years ago, which shut off direct mixing between the Atlantic and Pacific Oceans. This strongly affected the ocean dynamics of what is now the Gulf Stream and may have led to Northern Hemisphere ice cover. During the Carboniferous period, about 300 to 360 million years ago, plate tectonics may have triggered large-scale storage of carbon and increased glaciation. Geologic evidence points to a "megamonsoonal" circulation pattern during the time of the supercontinent Pangaea, and climate modeling suggests that the existence of the supercontinent was conducive to the establishment of monsoons.
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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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Among the most serendipitous discoveries that the Nimbus missions made possible was that of a gaping hole in the sea ice around Antarctica in the Southern Hemisphere winters of 1974–76. In a phenomenon that has not been observed since, an enormous, ice-free patch of water, called a polynya, developed three years in a row in the seasonal ice that encases Antarctica each winter. Located in the Weddell Sea, each year the polynya vanished with the summer melt, but returned the following year. The open patch of water may have influenced ocean temperatures as far down as 2,500 meters and influenced ocean circulation over a wide area.
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Ocean tracers are used to deduce small scale flow patterns, large-scale ocean circulation, water mass formation and changes, "dating" of water masses, and carbon dioxide storage and uptake. Tracers such are temperature, salinity, density, and other conservative tracers are often used to track currents, circulation and water mass mixing. An interesting example was when 28,000 plastic ducks fell over board from a container ship in the middle of the Pacific Ocean. The following twelve years oceanographers recorded where the ducks washed ashore, some thousands of miles from the spill site, and this data was used to calibrate and verify the circulation patters of the North Pacific Gyre.
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As deputy postmaster, Franklin became interested in the North Atlantic Ocean circulation patterns. While in England in 1768, he heard a complaint from the Colonial Board of Customs: Why did it take British packet ships carrying mail several weeks longer to reach New York than it took an average merchant ship to reach Newport, Rhode Island? The merchantmen had a longer and more complex voyage because they left from London, while the packets left from Falmouth in Cornwall. Franklin put the question to his cousin Timothy Folger, a Nantucket whaler captain, who told him that merchant ships routinely avoided a strong eastbound mid-ocean current.
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Changes in ocean circulation triggered by ongoing climate change could also add or magnify other causes of oxygen reductions in the ocean. In August 2017, a report suggested that the US meat industry and agroeconomic system are predominantly responsible for the largest-ever dead zone in the Gulf of Mexico. Soil runoff and leached nitrate, exacerbated by agricultural land management and tillage practices as well as manure and synthetic fertilizer usage, contaminated water from the Heartland to the Gulf of Mexico. A large portion of the crops grown in this region are used as major feed components in the production of meat animals for agribusiness companies, like Tyson and Smithfield Foods.
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He attributed the whirlpool to divine forces and mentioned that it was much stronger than the previously known Sicilian whirlpool Charybdis. Most other writers of the time believed that the Moskstraumen played an important role in the ocean circulation, but, given a large number of tales and lack of scientific observations, grossly overestimated the size and power of the phenomenon. The Moskstraum, referred to simply as the Maelstrom, was the inspiration for Edgar Allan Poe's short story "A Descent into the Maelström" (1841), which brought the term maelstrom, meaning strong whirlpool, into the English language.The Merriam-Webster new book of word histories, 1991, p.
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With the application of ever- improving measurement techniques for single molecules, and correlation with other independent proxies in the geological record that can help constrain some variables, investigating the hydrogen isotope composition of leaf waxes can be extremely productive. Leaf wax δD data has been successfully applied to improving our understanding of climate driven changes in terrestrial hydrology, by demonstrating that ocean circulation and surface temperature have a significant effect on continental precipitation. Leaf wax δD values have also been used as records of paleoaltimetry to reconstruct the elevation gradients in ancient mountain ranges based on the effect of altitude on rain water δD.
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The entry of CFCs into the ocean makes them extremely useful as transient tracers to estimate rates and pathways of ocean circulation and mixing processes. However, due to production restrictions of CFCs in the 1980s, atmospheric concentrations of CFC-11 and CFC-12 has stopped increasing, and the CFC-11 to CFC-12 ratio in the atmosphere have been steadily decreasing, making water dating of water masses more problematic. Incidentally, production and release of sulfur hexafluoride (SF6) have rapidly increased in the atmosphere since the 1970s. Similar to CFCs, SF6 is also an inert gas and is not affected by oceanic chemical or biological activities.
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Changes in climate, permafrost, ice pack, and glacier formations pose a serious threat to the stability of global climate because these conditions are influenced and reinforced by positive feedback loops. Temperatures in the tundra are rising to the highest temperatures recorded in four centuries and are rising more rapidly than anywhere worldwide The land surfaces in the tundra are no longer reflecting radiation from the sun out of the atmosphere. Soils and open water are absorbing heat from the sun and leading to more warming. Changes in the tundra influence climate change in lower latitudes because air pressure changes are shifting global air and ocean circulation patterns.
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Equatorial Counter Current (in black) The Equatorial Counter Current is an eastward flowing, wind-driven current which extends to depths of 100-150m in the Atlantic, Indian, and Pacific Oceans. More often called the North Equatorial Countercurrent (NECC), this current flows west-to-east at about 3-10°N in the Atlantic, Indian Ocean and Pacific basins, between the North Equatorial Current (NEC) and the South Equatorial Current (SEC). The NECC is not to be confused with the Equatorial Undercurrent (EUC) that flows eastward along the equator at depths around 200m in the western Pacific rising to 100m in the eastern Pacific. In the Indian Ocean, circulation is dominated by the impact of the reversing Asian monsoon winds.
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The processes behind the timing and amplitude of these events (as recorded in ice cores) are still unclear. The pattern in the Southern Hemisphere is different, with slow warming and much smaller temperature fluctuations. Indeed, the Vostok ice core was drilled before the Greenland cores, and the existence of Dansgaard–Oeschger events was not widely recognised until the Greenland (GRIP/GISP2) cores were done; after which there was some reexamination of the Vostok core to see if these events had somehow been "missed". A closeup near 40 kyr BP, showing reproducibility between cores The events appear to reflect changes in the North Atlantic Ocean circulation, perhaps triggered by an influx of fresh water or rain.
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The events may be caused by an amplification of solar forcings, or by a cause internal to the earth system – either a "binge- purge" cycle of ice sheets accumulating so much mass they become unstable, as postulated for Heinrich events, or an oscillation in deep ocean currents (Maslin et al.. 2001, p25). More recently, these events have been attributed to changes in the size of the ice sheets and atmospheric carbon dioxide. The former determines the strength of the Atlantic Ocean circulation via altering the northern hemisphere westerly winds, gulf stream, and sea-ice systems. The latter modulates atmospheric inter-basin freshwater transport across Central America, which changes the freshwater budget in the North Atlantic and thus the circulation.
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The Day After Tomorrow is a 2004 American apocalyptic action film directed, co-produced, and co-written by Roland Emmerich. Based on the 1999 book The Coming Global Superstorm by Art Bell and Whitley Strieber, the film stars Dennis Quaid, Jake Gyllenhaal, Ian Holm, Emmy Rossum, and Sela Ward. It depicts catastrophic climatic effects following the disruption of the North Atlantic Ocean circulation in a series of extreme weather events that usher in global cooling and lead to a new ice age. Originally slated for release in the summer of 2003, The Day After Tomorrow premiered in Mexico City on May 17, 2004, and was released in the United States on May 28, 2004.
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At sufficiently high values of the applied field, ions are extracted from the cone tip by field evaporation or similar mechanisms, which then are electrically accelerated to high velocities – typically 100 km/s or more. Due to its very low thrust (in the micronewton (µN) to millinewton (mN) range), FEEP thrusters are primarily used for microradian, micronewton attitude control on spacecraft, such as in the ESA/NASA LISA Pathfinder scientific spacecraft. The FEEP thruster was also slated for installation on Gravity Field and Steady-State Ocean Circulation Explorer spacecraft, but the Gridded ion thruster was used instead. The first FEEP thruster operated in space was the IFM Nano Thruster, successfully commissioned in Low Earth Orbit in 2018.
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Although remote sensing has been steadily providing more and more in-situ measurements of geophysical variables, nothing comes close to the temporal and geospatial resolution of data provided by models. Although data can be subject to accuracy issues due to the extrapolation techniques used, the usage of modeled data is a commonly accepted practice in climate and meteorological sciences. Oftentimes, these models will be used in concert with in-situ measurements. A few well-known models are # NCEP/NCAR Reanalysis Project, an atmospheric model # Global Forecast System, a numerical weather prediction model # HYCOM, a general ocean circulation model Geological system models are frequently used in research, but have less public data availability than climatic and meteorological models.
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During the subsequent decades, the global satellite laser ranging network has evolved into a powerful source of data for studies of the solid Earth and its ocean and atmospheric systems. In addition, SLR provides precise orbit determination for spaceborne radar altimeter missions mapping the ocean surface (which are used to model global ocean circulation), for mapping volumetric changes in continental ice masses, and for land topography. It provides a means for subnanosecond global time transfer, and a basis for special tests of the Theory of General Relativity. The International Laser Ranging Service was formed in 1998 by the global SLR community to enhance geophysical and geodetic research activities, replacing the previous CSTG Satellite and Laser Ranging Subcommission.
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Further updates, based on the suspected, but unconfirmed, arrival of Sanchi oil at the island of Amami Ōshima, projected the contamination may reach the Ryukyu Island chain and potentially affect coral reefs there. However, ocean circulation models used by China's State Oceanic Administration in Qingdao showed a different path for the contamination, one that would instead bypass the coastal waters of Japan. The New York Times asserts that the environmental damage, including possible contamination of beaches, as well as the damage to the fishing industry, may be significant, and will be paid for by the involved parties and their insurers. A report by CNN stated that the slick grew in size to over by 19 January.
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The effects of global warming in the Arctic, or climate change in the Arctic include rising air and water temperatures, loss of sea ice, and melting of the Greenland ice sheet with a related cold temperature anomaly, observed since the 1970s. Related impacts include ocean circulation changes, increased input of freshwater, and ocean acidification. Indirect effects through potential climate teleconnections to mid latitudes may result in a greater frequency of extreme weather events (flooding, fires and drought), ecological, biological and phenology changes, biological migrations and extinctions, natural resource stresses and as well as human health, displacement and security issues. Potential methane releases from the region, especially through the thawing of permafrost and methane clathrates, may occur.
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In biodiversity science, geodesic grids are a global extension of local discrete grids that are staked out in field studies to ensure appropriate statistical sampling and larger multi-use grids deployed at regional and national levels to develop an aggregated understanding of biodiversity. These grids translate environmental and ecological monitoring data from multiple spatial and temporal scales into assessments of current ecological condition and forecasts of risks to our natural resources. A geodesic grid allows local to global assimilation of ecologically significant information at its own level of granularity. When modeling the weather, ocean circulation, or the climate, partial differential equations are used to describe the evolution of these systems over time.
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Feedbacks associated with sea ice and snow cover are widely cited as the main cause of recent terrestrial polar amplification. However, amplification is also observed in model worlds with no ice or snow. It appears to arise both from a (possibly transient) intensification of poleward heat transport and more directly from changes in the local net radiation balance (an overall decrease in outward radiation will produce a larger relative increase in net radiation near the poles than near the equator). Some examples of climate system feedbacks thought to contribute to recent polar amplification include the reduction of snow cover and sea ice, changes in atmospheric and ocean circulation, the presence of anthropogenic soot in the Arctic environment, and increases in cloud cover and water vapor.
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Rupert Nigel Pendrill Hadow known as Pen Hadow (British, born 26 February 1962), is an Arctic region explorer, advocate, adventurer and guide. He is the only person to have trekked solo, and without resupply by third parties, from Canada to the Geographic North Pole."After 64 days, 478 Miles, -45C, Pen Hadow makes History by walking Solo to the North Pole" The Times Newspaper Tuesday 20 May 2003 He is also the first Briton to have trekked, without resupply by third parties, to both the North and South Geographic Poles from the respective continental coastlines of North America and Antarctica. Hadow led the multi-award-winning £6.5m international research programme, Catlin Arctic Survey (2007-2012) which investigated sea ice volume, ocean acidification and ocean circulation.
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Idealised depiction (at equinox) of large-scale atmospheric circulation on Earth Long-term mean precipitation by month Atmospheric circulation is the large-scale movement of air and together with ocean circulation is the means by which thermal energy is redistributed on the surface of the Earth. The Earth's atmospheric circulation varies from year to year, but the large-scale structure of its circulation remains fairly constant. The smaller scale weather systems – mid-latitude depressions, or tropical convective cells – occur "randomly", and long-range weather predictions of those cannot be made beyond ten days in practice, or a month in theory (see Chaos theory and the Butterfly effect). The Earth's weather is a consequence of its illumination by the Sun, and the laws of thermodynamics.
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Because of the relatively long residence time of the ocean's thermohaline circulation, carbon transported as marine snow into the deep ocean by the biological pump can remain out of contact with the atmosphere for more than 1000 years. That is, when the marine snow is finally decomposed to inorganic nutrients and dissolved carbon dioxide, these are effectively isolated from the surface ocean for relatively long time-scales related to ocean circulation. Consequently, enhancing the quantity of marine snow that reaches the deep ocean is the basis of several geoengineering schemes to enhance carbon sequestration by the ocean. Ocean nourishment and iron fertilisation seek to boost the production of organic material in the surface ocean, with a concomitant rise in marine snow reaching the deep ocean.
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SACLANTCEN also features a unique facility in Europe: the Oceanography Calibrating Laboratory, created in the early 1980s, which provided instrument calibration according to the World Ocean Circulation Experiment (WOCE) standard in support of the Centre's activities as well as for most NATO navies and research laboratories. Most of the research activities required the support of ship assets managed by the SACLANTCEN Ship Management Office. At the turn of the 21st century, the T-Boat Manning had been in service for 45 years. The advantage of operations carried out with a silent ship were highlighted by the activity of NRV Alliance, which recorded about 170 days per year at sea, mostly dedicated to the Centre's activities but also chartered to other organisations.
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Physical oceanography is the sub-domain of oceanography which focuses on the study of physical conditions and processes within the ocean, including the physical properties and circulation of ocean waters. These matters influence the biodiversity by providing the setting in which the ecology and biodiversity evolve. The physical setting for the biodiversity of the South African coastal and offshore waters is mainly temperate continental shelf, slope and abyss in the South Atlantic and South-west Indian Oceans off the southern part of the continent of Africa. The geomorphology of this region has local effects on the ocean circulation, particularly effects on ocean currents and upwellings, which in turn affect the distribution of organisms and the environment in which they live.
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For the National Academy of Sciences, she worked with the Geophysics Study Committee (1989-1992) and Ocean Studies Board, as well as chair of the OSB nominating committee. While Chair of the National Academy of Sciences' Committee On Major U.S. Oceanographic Research Programs, she was involved with the generation of the 1999 Global Ocean Science: Toward an Integrated Approach consensus study report from the National Academies Press. While serving on the NAS Committee on the Evolution of the National Oceanographic Research Fleet, she was part of the 2009 Science at Sea: Meeting Future Oceanographic Goals with a Robust Academic Research Fleet consensus study report, also from the National Academies Press. She has served on the scientific steering committee of the World Ocean Circulation Experiment (WOCE).
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Sandstrom was principally concerned with the role of heating and cooling in driving ocean currents, and in the larger-scale ocean circulation in general. He asserted that thermal circulation can cause vigorous, steady circulation only if heating occurs at greater depths than cooling. This is known today as Sandström's theorem and represents an attempt at extending the well known result of classical thermodynamic theory that in order for a heat engine to perform positive work over a cycle, the work of expansion needs to occur at greater pressure than the work of contraction. Sandstrom's theorem is therefore technically true, as long as expansion in the fluid is caused by heating and contraction by cooling, and that greater depths occur at greater pressures.
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NASA and CNES, a French space agency, are joint partners in this mission. The main objectives of the Jason-1 satellite is to collect data on the average ocean circulation around the globe in order to better understand its interaction with the time varying components and the involved mechanisms for initializing ocean models. To monitor the low frequency ocean variability and observe the season cycles and inter-annual variations like El Niño and La Niña, the North Atlantic oscillation, the pacific decadal oscillation, and planetary waves crossing the oceans over a period of months, then they will be modeled over a long period of time due to the precise altimetric observations. It aims to contribute to observations of the mesoscale ocean variability, affecting the whole oceans.
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Some of these maxima even correlate well with salinity extrema. In order to obtain the structure for ocean circulation, the tritium concentrations were mapped on 3 surfaces of constant potential density (23.90, 26.02, and 26.81). Results indicated that the tritium was well-mixed (at 6 to 7 TU) on the 26.81 isopycnal in the subarctic cyclonic gyre and there appeared to be a slow exchange of tritium (relative to shallower isopycnals) between this gyre and the anticyclonic gyre to the south; also, the tritium on the 23.90 and 26.02 surfaces appeared to be exchanged at a slower rate between the central gyre of the North Pacific and the equatorial regions. The depth penetration of bomb tritium can be separated into 3 distinct layers.
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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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Idealised depiction of the global circulation on Earth Atmospheric circulation is the large-scale movement of air, and is a means by which thermal energy is distributed on the surface of the Earth, together with the much slower (lagged) ocean circulation system. The large-scale structure of the atmospheric circulation varies from year to year, but the basic climatological structure remains fairly constant. Latitudinal circulation occurs because incident solar radiation per unit area is highest at the heat equator, and decreases as the latitude increases, reaching minima at the poles. It consists of two primary convection cells, the Hadley cell and the polar vortex, with the Hadley cell experiencing stronger convection due to the release of latent heat energy by condensation of water vapor at higher altitudes during cloud formation.
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The thickness of the barrier layer is defined as the difference between mixed layer depth (MLD) calculated from temperature minus the mixed layer depth calculated using density. The first reference to this difference as the barrier layer was in a paper describing observations in the western Pacific as part of the Western Equatorial Pacific Ocean Circulation Study.Lukas, R., and E. Lindstrom, The Mixed Layer of the Western Equatorial Pacific-Ocean, Journal of Geophysical Research-Oceans, 96, 3343-3357, 1991 In regions where the barrier layer is present, stratification is stable because of strong buoyancy forcing associated with a fresh lens sitting on top of the water column. In the past, a typical criterion for MLD was the depth at which the surface temperature cools by 0.2 °C (see e.g.
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Plants transpire water from depths lower than 1 meter in many places and satellites like SMOS can only provide moisture content down to a few centimeters, but using repeated measurements in a day, the satellite can extrapolate soil moisture. The SMOS team of ESA hope to work with farmers around the world, including the United States Department of Agriculture to use as ground-based calibration for models determining soil moisture, as it may help to better understand crop yields over wide regions.How Dry We Are: European Space Agency To Test Earth's Soil Moisture Via Satellite-Science News, Science Daily Ocean salinity is crucial to the understanding of the role of the ocean in climate through the global water cycle. Salinity in combination with temperature determine ocean circulation by defining its density and hence thermohaline circulation.
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Other significant achievements are the joint US-UK-Soviet studies of the Gulf stream currents, known as the Mid-Ocean Dynamic Experiment (MODE),Guide to the Records of the Mid-Ocean Dynamics Experiment, 1970-1976 occasionally acting as chief scientist. Churgin, Frank Wang, George Saxton and Michael Loughridge led the first American oceanographic delegation to ChinaThe Structure of Oceanography in China and helped engineer a ground breaking data exchange agreement between the two countries. Churgin participated in developing an early e-mail system to connect National Oceanographic Data Centers around the world, based on the (DARPA) system which later became the Internet. He also worked with Ferris Webster and James Crease in accumulating data for the World Ocean Circulation Experiment (WOCE) study which is used today to help scientists understand the ocean’s effects on climate.
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Duplessy turned to the ocean because of its role as a climate regulator and its major impact on biogeochemical cycles, particularly the carbon cycle. His doctoral thesis work has focused on the geochemistry of stable carbon isotopes in the sea.Duplessy J.C., La géochimie des isotopes stables du carbone dans la mer, Université de Paris VI, Thèse de doctorat ès Sciences Physiques, 21 juin 1972 He showed how the distribution of the stable heavy carbon isotope, carbon-13, was governed by biological fractionations related to chlorophyll assimilation by phytoplankton, then by ocean circulation and finally, to a lesser extent, by gas exchanges between the ocean and the atmosphere. All these phenomena, which dominate the carbon cycle in the ocean, are now being taken into account to study the fate of carbon dioxide emitted by human activities.
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Jason-1 was built by Thales Alenia Space using a Proteus platform, under a contract from CNES, as well as the main Jason-1 instrument, the Poseidon-2 altimeter (successor to the Poseidon altimeter on-board TOPEX/Poseidon) Jason-1 was designed to measure climate change through very precise millimeter-per-year measurements of global sea level changes. As did TOPEX/Poseidon, Jason-1 uses an altimeter to measure the hills and valleys of the ocean's surface. These measurements of sea surface topography allow scientists to calculate the speed and direction of ocean currents and monitor global ocean circulation. The global ocean is Earth's primary storehouse of solar energy. Jason-1's measurements of sea surface height reveal where this heat is stored, how it moves around Earth by ocean currents, and how these processes affect weather and climate.
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The missions revealed the surprising variability of the ocean, how much it changes from season to season, year to year, decade to decade and on even longer time scales. They ended the traditional notion of a quasi-steady, large-scale pattern of global ocean circulation by proving that the ocean is changing rapidly on all scales, from huge features such as El Niño and La Niña, which can cover the entire equatorial Pacific, to tiny eddies swirling off the large Gulf Stream in the Atlantic. Topex/Poseidon satellite (on the left) measured an average annual Global Mean Sea Level rise of 3.1 mm/year, Jason-1 is measuring only 2.3 mm/year GMSL rise, and the Envisat satellite (2002–2012) is measuring just 0.5 mm/year GMSL rise. In this graph, the vertical scale represents globally averaged mean sea level.
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Because of the Champlain Sea's openness to the Atlantic Ocean, changes in the salinity of the Champlain Sea could have translated into the Northern Atlantic, thus possibly causing changes in ocean circulation and climate. In fact, the melting of the Laurentide Ice Sheet was so extensive that its melt water entered the Gulf of Mexico, Arctic Ocean, and Hudson Bay (Fig. 2) in addition to the Champlain Sea and the Atlantic Ocean. Terrestrial plant material, seeds, and marine shells from Champlain Sea core samples have been used as proxies for paleosalinity. By studying δ13C (change in carbon-13) of marine mollusks, it can be inferred that when they existed in the Champlain Sea, conditions were brackish (mixture of fresh and salt water) about 10.8 ka BP. The δ13C value of a core sample Melo-1 (see Fig.
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The model has been optimized to be highly parallelized, in order to facilitate rapid computation of large, complex problems. ADCIRC is able to apply several different bottom friction formulations including Manning's n-based bottom drag due to changes in land coverage (such as forests, cities, and seafloor composition), as well as utilize atmospheric forcing data (wind stress and atmospheric pressure) from several sources, and further reduce the strength of the wind forcing due to surface roughness effects. The model is also able to incorporate effects such as time-varying topography and bathymetry, boundary fluxes from rivers or other sources, tidal potential, and sub-grid scale features like levees. ADCIRC is frequently coupled to a wind wave model such as STWAVE, SWAN, or WAVEWATCH III, especially in storm surge applications where wave radiation stress can have important effects on ocean circulation and vice versa.
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Ocean observatories can collect data for different purposes from scientific research to environmental monitoring for marine operations or governance for the benefit of economy and society as a whole. Ocean observatories provide real- time, or near real time data allowing to detect changes as they happen, such as geo-hazards for example. Furthermore continuous time series data allow to investigate interannual-to-decadal changes and to capture episodic events, changes in ocean circulation, water properties, water mass formation and ecosystems, to quantify air-sea fluxes, and to analyse the role of the oceans for the climate. The data collected by the several ocean observatories around the globe on the sub-sea-floor, seafloor, and water column, allows to improve our knowledgeSeafloor Observatories, A New Vision of the Earth from the Abyss Favali, Paolo; Beranzoli, Laura; De Santis, Angelo; Springer, 2015.
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Beginning in earth sciences at Harvard, Betts-LaCroix contributed to the field of long-term regulation of oxygen on Earth over multi-100 Million-year timespans, quantifying the effect of the burial efficiency of organic carbon as a feedback mechanism. At MIT, he designed and built an autonomous, robotic system that enables research into ocean circulation patterns and climate change, by operating untended for up to one year at sea on battery power and collecting hyper-pure water samples at predetermined intervals. In work at Caltech, Betts-LaCroix moved into biophysics, publishing a paper in Science that has been cited by more than 700 subsequent scientific works. In this work, he, along with David Beratan and José Onuchic proved for the first time that electron-transfer rates in proteins are determined by the electron orbital interactions in the protein structure.
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The climate of Panamá is largely affected by the position of a low atmospheric pressure zone known as the Intertropical Convergence Zone (ITCZ) which also affects seasonal evolution of geostrophic currents in the Panamá Bight. During the rainy season (December through May), the ITCZ is located to the North of Panamá and produces light and variable winds and ocean circulation in the Panamá Bight is anticyclonic (west) which creates a southerly flowing coastal current. As a result of these punctuated seasonal movements of the ITCZ, Panamá experiences high seasonal rainfall often reaching more than 3000 mm/yr. Starting in October and continuing into the dry season (January to March) the ITCZ moves South of Panamá,Rodriguez- Rubio E, Jose Stuardo (2002) Variability of photosynthetic pigments in the Colombian Pacific Ocean and its relationship with the wind field using ADEOS-I data. Proc.
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Dr. Garner attended New York University from 1959 to 1962, where he graduated with a PhD in Physics on 22 October 1962. Dr. Garner returned to New Zealand in 1962, joining a team of scientists that founded the New Zealand Oceanographic Institute of the Department of Scientific and Industrial Research (today known as National Institute of Water and Atmospheric Research), then located in Hobson Street, Wellington, New Zealand. Dr. Garner immigrated with his family to Canada in 1968, as a physical oceanographer in the ocean circulation department at the Bedford Institute of Oceanography in Nova Scotia, Canada from February 1968 to July 1971, where his topics of research included effects around the Mid-Atlantic Ridge. He worked extensively on the oceanographic research vessels CSS Dawson and CSS Hudson (Canadian Scientific Ship, painted Survey Ship white, and run by the Bedford Institute of Oceanography), which today is the CCGS Hudson.
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The Surface Water and Ocean Topography (SWOT) mission is a future satellite altimeter jointly developed by NASA and CNES, the French space agency, in partnership with the Canadian Space Agency (CSA) and UK Space Agency (UKSA). The objectives of the mission are to make the first global survey of the Earth's surface water, to observe the fine details of the ocean surface topography, and to measure how terrestrial surface water bodies change over time. While past satellite missions like the Jason series altimeters (TOPEX/Poseidon, Jason-1, Jason-2, Jason-3) have provided variation in river and lake water surface elevations at select locations, SWOT will provide the first truly global observations of changing water levels, slopes, and inundation extents in rivers, lakes, and floodplains. In the world's oceans, SWOT will observe ocean circulation at unprecedented scales of 15-25 km, approximately an order of magnitude finer than current satellites.
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In 1994, a special issue of the Canadian Journal of Earth Sciences featured Labrador Sea studies. Nine of the 12 articles were co- authored by Claude Hillaire-Marcel. In 2001, he was lead author on a paper in Nature entitled "Absence of deep-water formation in the Labrador Sea during the last interglacial period", and he was one of several authors of an EOS article entitled "New Record Shows Pronounced Changes in Arctic Ocean Circulation and Climate". Most of his work has been around the shores of Canada, but he has carried out field studies or been involved in research in Africa (Algeria, Burundi, Egypt, Ethiopia, Kenya, Libya, Mali, Niger, Tanzania and Tunisia, the Middle East (Israel and Syria, Latin America (Chile, Mexico, Peru, and Uruguay), and Europe (France, Greece and Spain (including the Balearic and Canary island. Between 1977 and 2002 he co-authored 24 non- Quaternary scientific papers in the fields of agriculture, nutrition, and physical exercise.
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This new Project was endorsed by the IODE at the conclusion of the Portugal meeting, and the IOC subsequently approved this project in June 2001. The World Ocean Database represents the world’s largest collection of ocean profile-plankton data available internationally without restriction. Data comes from the: (a) Sixty-five National Oceanographic Data Centers and nine Designated National Agencies (DNAs) (in Croatia, Finland, Georgia, Malaysia, Romania, Senegal, Sweden, Tanzania, and Ukraine), (b) International Ocean Observing Projects such as the completed World Ocean Circulation Experiment (WOCE) and Joint Global Ocean Flux Study (JGOFS), as well as currently active programs such as CLIVAR and Argo, (c) International Ocean Data Management Projects such as the IOC/IODE Global Oceanographic Data Archaeology and Rescue Project (GODAR), and (d) Real-time Ocean Observing Systems such as the IOC/IODE Global Temperature-Salinity Profile Project (GTSPP). All ocean data acquired by WDC Silver Spring – USA are considered as part of the WDC archive and are freely available as public domain data.
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Like its two predecessors, OSTM/Jason-2 used high-precision ocean altimetry to measure the distance between the satellite and the ocean surface to within a few centimeters. These very accurate observations of variations in sea surface height—also known as ocean topography—provide information about global sea level, the speed and direction of ocean currents, and heat stored in the ocean. Jason-2 was built by Thales Alenia Space using a Proteus platform, under a contract from CNES, as well as the main Jason-2 instrument, the Poseidon-3 altimeter (successor to the Poseidon and Poseidon 2 altimeter on- board TOPEX/Poseidon and Jason-1) Scientists consider the 15-plus-year climate data record that this mission extended to be critical to understanding how ocean circulation is linked to global climate change. OSTM/Jason-2 was launched on June 20, 2008, at 07:46 UTC, from Space Launch Complex 2W at Vandenberg Air Force Base in California, by a Delta II 7320 rocket.
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Many local effects can influence ice δD in addition to temperature. These effects include moisture origin and transport pathways, evaporation conditions and precipitation seasonality, which can be accounted for in more complicated models. Nevertheless, the Vostok ice core record shows some very important results: (1) A consistent δD depletion of ~70‰ during the last four glacial periods compared to interglacial times, corresponding to a cooling of 8 °C in Antarctica; (2) A consistent drop of atmospheric CO2 concentration by 100 ppmv and CH4 drop by ~300 ppbv during glacial times relative to interglacials, suggesting a role of greenhouse gases in regulating global climate; (3) Antarctic air temperature and greenhouse gas concentration changes precede global ice volume and Greenland air temperature changes during glacial terminations, and greenhouse gases may be an amplifier of insolation forcing during glacial-interglacial cycles. Greenland ice core isotope records, in addition to showing glacial-interglacial cycles, also shows millennial-scale climate oscillations that may reflect reorganization in ocean circulation caused by ice melt charges.
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Subscribers to the newsgroup took up the challenge and, despite Hyde's protests, raised the $100. Hyde's review on Google Groups criticized the film's depiction of weather which stopped at national borders; it was "to climate science as Frankenstein is to heart transplant surgery". Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research, an expert on thermohaline circulation and its effect on climate, said after a talk with scriptwriter Jeffrey Nachmanoff at the film's Berlin preview: > Clearly this is a disaster movie and not a scientific documentary, [and] the > film makers have taken a lot of artistic license. But the film presents an > opportunity to explain that some of the basic background is right: humans > are indeed increasingly changing the climate and this is quite a dangerous > experiment, including some risk of abrupt and unforeseen changes ... Luckily > it is extremely unlikely that we will see major ocean circulation changes in > the next couple of decades (I'd be just as surprised as Jack Hall if they > did occur); at least most scientists think this will only become a more > serious risk towards the end of the century.
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Benjamin Franklin's chart of the Gulf Stream printed in London in 1769 European discovery of the Gulf Stream dates to the 1512 expedition of Juan Ponce de León, after which it became widely used by Spanish ships sailing from the Caribbean to Spain. A summary of Ponce de León's voyage log on April 22, 1513, noted, "A current such that, although they had great wind, they could not proceed forwards, but backwards and it seems that they were proceeding well; at the end it was known that the current was more powerful than the wind." Benjamin Franklin became interested in the North Atlantic Ocean circulation patterns. In 1768, while in England, Franklin heard a curious complaint from the Colonial Board of Customs: Why did it take British packets several weeks longer to reach New York from England than it took an average American merchant ship to reach Newport, Rhode Island, despite the merchant ships leaving from London and having to sail down the River Thames and then the length of the English Channel before they sailed across the Atlantic, while the packets left from Falmouth in Cornwall.
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Based on Ekman theory and geostrophic dynamics, the analysis of near-surface currents, i.e. tropical Pacific near-surface currents, can be generated by using high resolution data of wind and altimeter sea level. The surface velocity is defined as the motion of a standard World Ocean Circulation Experiment/Tropical Ocean-Global Atmosphere (WOCE/TOGA) 15m drogue drifter. Near-surface Ekman velocity can be estimated with variables which best represent the ageostrophic motion of the WOCE/TOGA 15m drogue drifters relative to the surface wind stress. Geostrophic velocities are calculated with sea level gradients which are derived from TOPEX/Poseidon sea surface height analyses (TOPEX/Poseidon altimeter sea level anomalies from along-track data is used here, interpolated to 1°X1°grid, spanning the domain of 25°N-25°S,90°E-290°E, during Oct1992-Sep1998).Fu, L., E. J. Christensen, C. A. Yamarone, M. Lefebvfe, Y. Menard, M. Dorer, and P. Escudier, 1994: TOPEX/POSEIDON mission overview, J. Geophys. Res., 99, 24,369-24,382. Geostrophic and Ekman velocity are assumed to satisfy the lowest-order dynamics of the surface velocity, and they can be obtained independently from surface height and wind stress data.
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Aside from chlorofluorocarbons, tritium can act as a transient tracer and has the ability to "outline" the biological, chemical, and physical paths throughout the world oceans because of its evolving distribution.Jenkins, William J. et al, 1996: "Transient Tracers Track Ocean Climate Signals" Oceanus, Woods Hole Oceanographic Institution. Tritium has thus been used as a tool to examine ocean circulation and ventilation and, for such purposes, is usually measured in Tritium Units where 1 TU is defined as the ratio of 1 tritium atom to 1018 hydrogen atoms, approximately equal to 0.118 Bq/liter. As noted earlier, nuclear weapons testing, primarily in the high-latitude regions of the Northern Hemisphere, throughout the late 1950s and early 1960s introduced large amounts of tritium into the atmosphere, especially the stratosphere. Before these nuclear tests, there were only about 3 to 4 kilograms of tritium on the Earth's surface; but these amounts rose by 2 or 3 orders of magnitude during the post-test period. Some sources reported natural background levels were exceeded by approximately 1,000 TU in 1963 and 1964 and the isotope is used in the northern hemisphere to estimate the age of groundwater and construct hydrogeologic simulation models.
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