Meltdown countdown

ice sheet in North America is doomed to disappear fast. The Barnes Ice Cap is melting at a rapid pace, driven by increased greenhouse gases that have elevated Arctic temperatures. The ice cap, now 500 metres thick, is slated to melt in about 300 years under business-as-usual greenhouse gas emissions. The results provide compelling evidence that the current level of warming has never happened in the past 2.5 million years.

Geophysical Research Letters, March 20