Paris | Deep, cold ocean currents from the North Atlantic blunt the effect of global warming on Antarctica and slow the rise of sea levels, according to a study published today. This icy insulation of the snowy continent, covered by a sheath of ice up to four kilometres (2.5 miles) thick, could last for centuries, the research published in Nature Geoscience said.
That’s good news to hundreds of millions of people in low-lying regions who are threatened by seas set to rise up to a metre by the end of the century, according to the latest report by the UN climate science panel.
Newer studies suggest the ocean waterline could go up even more, pushed by surface water that expands as it warms, along with runoff from glaciers and two huge ice sheets. One of those ice sheets sits atop Greenland.
The other is on West Antarctica, a sliver of the larger continent that is warming faster than the rest. If East Antarctica were melting at the same rate, the impact on human settlements along coastlines worldwide would be truly catastrophic.
Scientists have long known that climate change has affected Antarctica’s Southern Ocean far more slowly over the last half-century than oceans elsewhere. They also know why: the sheer vastness of the continent’s ice sheet and the reflective sea ice that surrounds it, along with the winds and ocean currents that circle the continent like a buffer zone.