Researchers examining 43 million satellite measurements of Antarctica’s thinning ice sheets and 7 million of Greenland’s, show that the ice is melting faster than expected. Published in Nature the research is the most comprehensive picture to date of the melting glaciers, allowing scientists to better predict how sea levels may rise.
Researchers say that the most extreme ice loss is due to glaciers speeding up where they flow into the sea. With these new measurements, gathered by lasers on satellites, the authors found that the thinning of glaciers is now occurring at all latitudes in Greenland. The melting has also increased on Antarctic coastlines and has spread deep into the interior of ice sheets.
“We were surprised to see such a strong pattern of thinning glaciers across such large areas of coastline – it’s widespread and in some cases thinning extends hundreds of kilometres inland. We think that warm ocean currents reaching the coast and melting the glacier front is the most likely cause of faster glacier flow. This kind of ice loss is so poorly understood that it remains the most unpredictable part of future sea level rise,” says lead author Dr Hamish Pritchard from the British Antarctic Survey.
Fast-mowing glaciers are melting quicker than slow-flowing ice, according to the study. In Greenland the researchers found that 81 of 111 fast moving glaciers are melting at double the rate of slow-flowing ice at the same latitude.
Some glaciers in West Antarctica—such as Pine Island, Smith, and Thwaites glaciers—are thinning by up to nine meters every year.
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