Clearest indication yet that polar ice sheets are melting fast

Disko Bay near the Greenlandic town of Ilulissat

Ian Joughlin

A research paper has drawn on data from NASA and ESA satellites to produce the most comprehensive assessment of ice sheet losses in Antarctica and Greenland to date.

The paper, published on 29 November in the journal Science, shows that melting Antarctic and Greenland ice sheets have added 11.1mm (0.43") to global sea levels since 1992. The paper, A reconciled estimate of ice sheet mass balance, was drawn together by an international team of 47 researchers, using data collected from ten satellite missions to produce the most consistent picture of polar ice sheets ever recorded. The resulting findings have been able to reconcile the differences that existed between previous ice sheet studies, by carefully matching observation periods and survey areas.

The findings of the international team—the Ice Sheet Mass Balance Inter-comparison Exercise (IMBIE)—give clarity to the Intergovernmental Panel on Climate Change's 2007 reports. The latter study's time scale was so broad that it was not possible to tell if Antarctica was growing or shrinking, but the use of data from NASA and ESA satellites have confirmed that both Antarctica and Greenland are losing ice.