Antarctica defies global warming, stays cool

The Southern Ocean off Antarctica may be among the last places on Earth to feel the impact of man-made climate change, with a lag of centuries to affect waters emerging from up to 5,000 meters  deep, the US study said.

Many people who doubt mainstream scientific findings that human use of fossil fuels is warming the planet often point to the paradox of expanding winter sea ice off Antarctica and a rapid shrinking of ice in the Arctic. “Our findings are a step toward resolving the mystery,” lead author Kyle Armour said.

Monday’s report found that warm waters in the Gulf Stream cool as they flow north into the North Atlantic, then sink and loop south towards Antarctica as part of an aquatic conveyor belt that takes centuries to complete. Eventually, gale force winds in the Southern Ocean around Antarctica blow surface waters northwards and draw the chill, ancient waters from the depths. That upwelling explains why the surface of the Southern Ocean have warmed by 0.02 degree C per decade since 1950.