In Greenland’s Melting Ice, A Warning on Hard Climate Choices

28/06/2019

#global warming #ice*sheet #climate change #greenland

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Greenland is melting at an unprecedented rate, causing vast quantities of ice to disappear and global sea levels to rise. The fate of the ice sheet is not sealed, but unless CO2 emissions are sharply cut, the long-term existence of Greenland’s ice is in doubt.

During the warmest stretch, runoff from the ice sheet amounted to about 2 billion tons, which meant that at the same time Greenland was losing water, the North Atlantic was gaining it. Some areas on the island were 40 degrees Fahrenheit above normal for this time of year.

“We didn’t see anything like this prior to the late 1990s,” Thomas Mote, a University of Georgia scientist who monitors summer melting on the ice sheet, explained to CNN. “The melting is big and early,” Jason Box, a climatologist with the geological survey of Denmark and Greenland, informed the Washington Post.

Greenland’s ice sheet covers about 80 percent of the island, and measures about 660,000 square miles; in its center, it runs to a depth of about two miles. According to the most recent NASA studies, the ice sheet holds enough water to raise sea levels by about 24 feet, should it ever disappear completely.

What seems clear now is that Greenland is no longer changing in geological time. It is changing in human time.

Yet we now know that the Greenland of today is different from the Greenland that Rink experienced. The ice sheet is melting more, and melting earlier in summer, and melting in ways that computer models suggest will ultimately threaten its long-term existence.

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