58:. As saltwater freezes, salt is expelled from the ice into the surrounding water. The oxygen content in bottom water is high due to ocean circulation. In the Antarctic, salty and cold surface water sinks to lower depths due to its high density. As the surface water sinks, it carries oxygen from the surface with it and will spend an enormous amount of time circulating across the seafloor of ocean basins. Oxygen-rich water moving throughout the bottom layer of the ocean is an important source for the respiration of benthic organisms. Bottom waters flow very slowly, driven mainly by slope topography and differences in temperature and salinity, especially compared to
114:. Ventilation has also slowed down as a result of global warming. Antarctic Bottom Water has such high oxygen content that it is able to contribute to the ventilation of the deep ocean by acting as a circulatory system. Long-term shifts in temperature increase have slowed the rate of ocean ventilation. As the atmosphere warms, that decreases the formation of sea ice in Antarctica, thus decreasing the density of the surrounding water. The decreased density leads to a slower rate of convection ultimately slowing down deep water formation processes. Essential processes like
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54:. This water is characterized by low salinity and nutrient content. Generally, low salinity from seasonal ice melt and freshwater river output characterizes bottom water produced in the Antarctic. However, during colder months, the formation of sea ice is a crucial process that raises the salinity of bottom water through
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Changes in the characterization of
Antarctic Bottom Water have been monitored in the Southern Ocean. The Antarctic Bottom Water’s temperature has increased and the salinity continues to freshen. Since the water mass is heating up and getting fresher, the density is significantly lowering. This has to
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is more isolated, due to the topography of the Arctic Ocean floor and the surrounding Arctic shelves. Deep
Western Boundary Currents carry the Antarctic Bottom Water northward in the South Atlantic Ocean. The Antarctic Bottom Water shifts east when it reaches the equator, thus turning it into an
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due to its colder temperature and higher density. Salinity can be used to compare the movement between fresh
Antarctic Bottom Water (roughly 34.7 psu) and saltier North Atlantic Deep Water. Antarctic Bottom Water can be distinguished from other intermediate and deep water masses by its cold, low
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decrease. When the particles nearly reach the floor, they are carried back to the head of estuary to accumulate at the point where the salinity of the surface and bottom waters become comparable and the bottom flow decreases. This process results is a distinguished pile of mud at this point.
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eastern boundary current along the mid-Atlantic Ridge. The movement of the
Antarctic Bottom Water across isopycnals is limited by deep sills. Sills are shallow seafloor regions that stop water from flowing across basins.
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is created, with lower salinity levels upstream, which generates the upstream flow of the bottom water. Mud particles carried by river begin settling down as the current and
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begin to digress. Without upwelling, cold, nutrient-rich water can’t be recycled to the surface to create areas of high productivity.
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Milton Joseph
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Descriptive
Physical Oceanography, Talley, Pickard, Emery, and Swift, 6th edition. Elsiver Press (2011),
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Descriptive
Physical Oceanography, Talley, Pickard, Emery, and Swift, 6th edition. Elsiver Press (2011),
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Descriptive
Physical Oceanography, Talley, Pickard, Emery, and Swift, 6th edition. Elsiver Press (2011),
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Descriptive
Physical Oceanography, Talley, Pickard, Emery, and Swift, 6th edition. Elsiver Press (2011),
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David E. Alexander, Rhodes
Whitmore Fairbridge (eds.) (1999) "Encyclopedia of Environmental Science",
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heating up the atmosphere and the ocean resulting in sea ice melt, sea level rise, and
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52:ocean floor
383:Categories
248:References
203:chlorinity
143:turbulence
28:water body
24:water mass
199:anaerobic
178:June 2008
122:Estuaries
116:upwelling
36:chemistry
236:See also
139:gradient
106:do with
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207:acidity
136:isohale
128:estuary
40:ecology
32:physics
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26:in a
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