The slowdown of global warming in the first decade of the twenty-first century is best explained by what is happening in the ocean – and not in the Pacific, as previously thought, but in the Atlantic and southern Arctic. This is evidenced by the results of a study conducted by Chinese scientists, which is told in the pages of the journal Science.
Chen Xiangyang (Xianyao Chen) and Ka-Kit Tung (Ka-Kit Tung) examined data from buoys, gauges – oceanographic sensors capable of moving up and down in the water column, and traced how heat moves in the oceans. It turns out that in the beginning of the century due to the increased salinity of the excess heat from the surface of the water “left” in great depth (up to one and a half kilometers).
This is not an accidental phenomenon: the salinity of the Atlantic and Arctic Oceans Southern varies regularly cycles 25-30 years. After the previous “hot” phase of the turn cooling, says Ka-Kit Tung. The cycle begins when the saltier (and dense) water on the surface of the North Atlantic begins to “put pressure” on the deep water, which quickly transfers heat “inside” of the ocean. Record the salinity of surface waters in the 2000s coincided with the warming temperatures in the bottom column, said Tong.
According to oceanographers, cold 1945-1975, the first years, when the world feared even a new ice age, as occurred times the previous cycle of oceanic cooling. A rapid warming in the 1970-1990 years, about 50 percent was due to global warming, and another 50 percent – with the natural cycle of the Atlantic.
If this hypothesis is correct, then a relatively cool period will last for 10 -15 years and then resume a powerful global warming. However, other processes on the surface of the planet threaten to disrupt the natural cycle. Fresh water from the melting ice of the Arctic Ocean flows into the North Atlantic and salinity changes.
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