The IPCC’s report a few years ago on climate change appears to have vastly underestimated the rate of Arctic ice melt. This is confirmed by data reported in a Globe article today, Arctic ice is melting faster than expected, report says, by the Arctic Monitoring and Assessment Program.
It says that Arctic temperatures in the past six years were the highest since measurements began in 1880, and that feedback mechanisms believed to accelerate warming in the climate system have now started kicking in.
One mechanism involves the ocean absorbing more heat when it’s not covered by ice, which reflects the sun’s energy. That effect has been anticipated by scientists “but clear evidence for it has only been observed in the Arctic in the past five years,’’ AMAP said.
So what exactly does that mean?
The melting of Arctic glaciers and ice caps, including Greenland’s massive ice sheet, are projected to help raise global sea levels by 35 to 63 inches by 2100, AMAP said, though it noted that the estimate was highly uncertain.
That’s up from a 2007 projection of 7 to 23 inches by the UN panel, which didn’t consider the dynamics of ice caps in the Arctic and Antarctica.