Greenland's ice sheet melting seven times faster than in 1990s

https://www.theguardian.com/environment/2019/dec/10/greenland-ice-sheet-melting-seven-times-faster-than-in-1990s

Fiona Harvey in Madrid
Tue 10 Dec 2019 11.00 EST

Greenland’s ice sheet is melting much faster than previously thought, threatening hundreds of millions of people with inundation and bringing some of the irreversible impacts of the climate emergency much closer.

Ice is being lost from Greenland seven times faster than it was in the 1990s, and the scale and speed of ice loss is much higher than was predicted in the comprehensive studies of global climate science by the Intergovernmental Panel on Climate Change, according to data.

That means sea level rises are likely to reach 67cm [26 in] by 2100, about 7cm more than the IPCC’s main prediction. Such a rate of rise will put 400 million people at risk of flooding every year, instead of the 360 million predicted by the IPCC, by the end of the century.

Sea level rises also add to the risk of storm surges, when the fiercer storms made more likely by global heating batter coastal regions. These impacts are likely to strike coastal areas all around the world.

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Greenland has lost 3.8tn tonnes of ice since 1992, and the rate of ice loss has risen from 33bn tonnes a year in the 1990s to 254bn tonnes a year in the past decade. Greenland’s ice contributes directly to sea level rises as it melts because it rests on a large land mass, unlike the floating sea ice that makes up much of the rest of the Arctic ice cap.

About half of the ice loss from Greenland was from melting driven by air surface temperatures, which have risen much faster in the Arctic than the global average, and the rest was from the speeding up of the flow of ice into the sea from glaciers, driven by the warming ocean.

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Louise Sime, a climate scientist at the British Antarctic Survey, said of the new paper: “This finding should be of huge concern for all those who will be affected by sea level rise. If this very high rate of ice loss continues, it is possible that new tipping points may be breached sooner than we previously thought.”