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over this period was observed in the North Sea, East China Sea, Sea of Japan/East Sea,
Newfoundland/Labrador Shelf, and Black Sea LMEs (Sherman, Aquarone, and Adams,
2009 ) .
Multi-model simulations aimed at elucidating the response ofocean ecosystems tocli-
mate warming (Sarmiento et al ., 2004 ) show an increase in SST everywhere in the global
ocean. This analysis brings out changes in biome areas that may be expected to result from
global warming, including a large reduction in the marginal sea ice biome and an increase
in the permanently stratified subtropical gyre biome. The subpolar gyre biome expands
while the seasonally stratified subtropical gyre biome contracts.
Recent scientific findings show, furthermore, that human actions are now reaching all
observed ocean areas. They confirm that the ocean has absorbed 90% of the heat increase
of the planet over the past 50 years. The ocean's heat content has increased about 20 times
more than that of the atmosphere. The warming has penetrated at least 2000 metres into
the deep sea. There have been interpretations of observations suggesting that the meridion-
al over-turning in the North Atlantic has slowed down, associated with a related decrease
of the formation of North Atlantic deep water (NADW), but evidence from sedimentary
records is more consistent with an increased production of NADW during cyclic climate
warming periods, rather than the reverse (Wefer and Berger, 2001 ) . Altered deep water
formation, the related overflow across the Denmark Strait, and the thermohaline circulation
may then be coupled to a decrease in the surface layer density due to climate-induced sea
ice melt and subsequent export of low salinity Arctic waters through the Fram Strait into
the Greenland, Iceland, and Norwegian seas.
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