Gadabout sidled to starboard, and grapnels were thrown up into the trees to hold her alongshore.
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Longshore drift by swash occurs either due to beach cusp morphology or due to oblique incoming waves causing strong alongshore swash motion. Under the influence of longshore drift, when there is no slack-water phase during backwash flows, sediments can remain suspended to result in offshore sediment transport. Beachface erosion by swash processes is not very common but erosion can occur where swash has a significant alongshore component.
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Lac-Sergent is a community situated alongshore Sergent Lake in Portneuf Regional County Municipality in the Canadian province of Quebec. It is about north-west of Quebec City.
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The construction of the Dubai Palm Islands has had a significant impact on the surrounding environment, resulting in changes to area wildlife, coastal erosion, alongshore sediment transport and wave patterns. Sediment stirred up by construction has suffocated and injured local marine fauna and reduced the amount of sunlight which filters down to seashore vegetation. Variations in alongshore sediment transport have resulted in changes in erosion patterns along the UAE coast, which has also been exacerbated by altered wave patterns as the waters of the Persian Gulf attempt to move around the new obstruction of the islands. Dubai's megaprojects have become a favorite cause of environmentalists.
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On low slope sandy coastlines, inlets often separate barrier islands and can form as the result of storm events. Alongshore sediment transport can cause inlets to close if the action of tidal currents flowing through an inlet do not flush accumulated sediment out of the inlet.
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From then on the running was fairly easy, first to the mouth of the Grande Ronde River, where they halted alongshore. The next day, April 27, the easy running ended when at 7:00 a.m. the boat reached the Wild Goose Rapids, which had a reputation as a fierce stretch of whitewater.These were located above Asotin, Washington.
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The alongshore shape of spur and groove formations varies from smoothly varying rounded spurs, to flat spurs with shallow rectangular grooves, or deeply cut rectangular or overhanging channels sometimes called buttresses. Spur and groove formations have typical scales of: spur height 0.5 to 10 m, alongshore wavelength 5 to 150 m, width of groove 1 to 100 m, and found in depths from 0 to 30 m. The mechanism for maintaining preferential coral growth on the spur is thought to be caused by higher wave stress on the spur which causes sediment to be shed towards the groove and downslope and preferential coral growth on the spur. Thus, it is believed that spur and grooves are essentially constructional in formation, while a less important mechanism may occur from sediment scour in the grooves.
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Dynamic tidal power doesn't require a very high natural tidal range, but instead an open coast where the tidal propagation is alongshore. Such tidal conditions can be found in many places around the world, which means that the theoretical potential of DTP is very high. Along the Chinese coast for example, the total amount of available power is estimated at 80 - 150 GW.
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She then steamed back to Lagos on one engine in 1998. Aradu was refitted, refurbished and equipped after being alongshore for over twelve years. The ship proved it was still seaworthy by taking part in celebrations commemorating the 200th anniversary of the Battle of Trafalgar by sailing to Great Britain in August 2005 to join 100 warships from 36 navies.
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Constructional margins are the "classic" mode of passive margin sedimentation. Normal sedimentation results from the transport and deposition of sand, silt, and clay by rivers via deltas and redistribution of these sediments by longshore currents. The nature of sediments can change remarkably along a passive margin, due to interactions between carbonate sediment production, clastic input from rivers, and alongshore transport. Where clastic sediment inputs are small, biogenic sedimentation can dominate especially nearshore sedimentation.
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This dense-water pool, named the Kangaroo Island Pool, drifts along the shelf bottom just offshore of Kangaroo Island and the Eyre Peninsula. When a classical wind-driven upwelling event occurs, normally two to three times a summer, cold water is upwelled from the pool, not directly from the ocean floor.McClatchie, S., J. F. Middleton, and T. M. Ward (2006), Water mass and alongshore variation in upwelling intensity in the eastern Great Australian Bight, J. Geophys. Res., 111, C08007, .
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A Kelvin wave is a wave in the ocean or atmosphere that balances the Earth's Coriolis force against a topographic boundary such as a coastline, or a waveguide such as the equator. A feature of a Kelvin wave is that it is non- dispersive, i.e., the phase speed of the wave crests is equal to the group speed of the wave energy for all frequencies. This means that it retains its shape as it moves in the alongshore direction over time.
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By alongshore winds, upwelling current flows to the coast. Near the equator, the East African Coast Current (EACC) flows northward across the equator. The southern Somali Current flows northward as an extension of the EACC from south to the 3-4°N. Northeastward current (Jun-Sep, Summer Monsoon): The Somali Current begins developing its strength from mid-May with the summer monsoon onset, and current velocities rapidly grow to the maximum until June and September with the southwest monsoon blowing.
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With the lake receding, the ancient town confined to the Castrum had lost its strategic position: no more direct access to the port, or to the new trade routes alongshore. When Peter II of Savoy gradually extended his rule over the Pays de Vaud (Land of Vaud), he managed to impose road tolls as well as port and fishing taxes. He founded the new town ("Ville Neuve") of Yverdon, defended by walls and a castle. Construction works were launched around 1259 and attracted many settlers.
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Habitat for the young fish is predominately alongshore backwaters and associated shorelines of more alluvial reaches of the turbulent and turbid rivers of the Colorado system. In contrast, adults reside in more well-defined channels, where they seek eddy habitats and prey on suckers and minnows. Colorado pikeminnows are potamodromous, making freshwater spawning migrations to home in on their natal areas. These migrations can begin as upstream or downstream movements, depending on the location of home range of individuals, and may involve 100 km or more.
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Coastal margins have high sedimentation rates due to sediment input by rivers, which account for the vast majority of sediment delivery to the ocean. In most cases, sediments are deposited near the river mouth or are transported in the alongshore direction due to wave forcing. In some places sediment falls into submarine canyons and is transported off-shelf, if the canyon is sufficiently large or the shelf is narrow. Coastal margins also contain diverse and plentiful marine species, especially in places that experience periodic upwelling.
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Marine canyons are magnets for sediment because as currents carry sediment on the shelf in the alongshore direction, the path of the current crosses canyons perpendicularly. When the same amount of water flow is suddenly in much deeper water it slows down and deposits sediment. Due to the extreme depositional environment, carbon burial rates in the Nazare Canyon near Portugal are 30 times greater than the adjacent continental slope. This canyon alone accounts for about 0.03% of global terrestrial organic carbon burial in marine sediments.
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The high levels of sex segregation and fragmentation of different populations in Hector's dolphin have been discussed as contributing to the overall population decline, as it becomes more difficult for males to find a female and copulate. The Allee effect begins to occur when a low-density population has low reproductive rates leading to increased population decline. In addition, low gene flow between populations may result from this species' high foraging site fidelity. Hector's dolphins have not been found to participate in alongshore migrations, which may also contribute to their lack of genetic diversity.
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Banks dory used as work boat by CSS Acadia It is often assumed that the Banks dory was the original dory. In fact, the Swampscott dory preceded the Banks dory by fifty years.Gardner (1987) page 33 The Banks dories first appeared in the 1830s and were probably the most numerous at their height of popularity. They were "designed specifically as a ships boat but it became so well known and so common a type that it not only was used alongshore but influenced the design of some local fishing boats".
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If this system is relatively strong during winter, there will be an increase in northward transport of waters along the Alaskan current from southerly winds. Haida eddies have been documented to form predominantly in the winter when bifurcation is south, and favorable atmospheric conditions are met to intensify the subpolar gyre. With these conditions, Haida eddy formation has also been documented to occur from baroclinic instabilities from alongshore wind reversals, equatorial Kelvin waves, and bottom topography. Baroclinic instabilities form when tilting or sloping of isopycnals (horizontal lines of constant density) form.
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While bulkheads may serve their purpose to slow erosion at a bluff or beachfront, they commonly cause a domino effect of change to the beach profile. The increased wave reflection caused by their presence can result in an increased re-suspension of sand in the water in front of the bulkhead. This can lead to more sand being distributed in the alongshore direction, away from the beach profile. Due to coastal littoral drift, the sand would then instead be distributed toward the ends of the bulkheads, leaving larger gravel and sometimes bedrock in place of the once sandy beach.
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These debris fields exist in all the archipelago of the Azores, but are concentrated on the island of São Jorge . The island is volcanic in character with steep cliffs running down to the coast, and where fajãs extend into the sea caused by the collapse of these cliffs. The long fetch of the Azores is a high-energy wave climate, and the steep submarine slopes and absence of shallow shelves produce localized patterns of wave shoaling, refraction and diffraction: especially during storms. This leads to the fragmentation of the coast into a number of dynamic cells whose sediment alongshore is limited by impermeable boundaries.
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The ShoreZone program currently extends from Oregon to Alaska with spatially contiguous aerial imagery and habitat maps that are available online.ShoreZone on line ShoreZone is a mapping program that uses oblique aerial images acquired at low altitude, and during the lowest daylight tides of the year, to inventory alongshore and across-shore geomorphological and biological features of the Pacific Northwest intertidal shoreline. Habitat attributes are interpreted from the aerial images and categorized in a geographic database. The mapping project was first developed as an oil spill response tool for British Columbia, and now ShoreZone extends from Oregon to Alaska and has many other uses including ecological studies, marine conservation planning, coastal flooding and vulnerability assessments, and community education.
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Baroclinic instabilities from alongshore wind reversals occur when a persistent wind along the coast changes direction. For example: in the Gulf of Alaska average winds travel from the south, poleward (termed southerly winds), but during a wind reversal the winds will abruptly shift to a northwesterly wind (coming from the northwest), and the coastal current that was being pushed north will now be pushed south. This change in direction causes rotation in an originally northward flowing current, which results in tilting isopyncals. Kelvin waves that form along the equator are able to travel along the west coast of North America to the Gulf of Alaska, where their presence can cause disruptions in the poleward current and form baroclinic instabilities.
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