Ice melt found across 97 percent of Greenland, satellites show

Three satellites found that 97 percent of Greenland -- the land mass second only to Antarctica for its volume of ice -- underwent a thaw never before seen in 33 years of satellite tracking, NASA reported Tuesday.
Satellite experts at first didn't trust their readings, especially since they showed an incredible acceleration. Over four days, Greenland's ice sheet -- which covers 683,000 square miles -- went from 40 percent in thaw to nearly entirely in thaw.
"This was so extraordinary that at first I questioned the result: Was this real or was it due to a data error?" Son Nghiem of NASA's Jet Propulsion Lab in Pasadena, Calif., said in NASA's statement about the findings.
Scientists on the ground in Greenland had been reporting an unusually warm summer thaw, including damage at a snow airfield and strong runoff threatening a bridge, Tom Wagner, who manages NASA's ice research programs, told NBC News.
Ice cores from Greenland's highest region do reveal that such island-wide thaws have happened every 150 years or so, at least over the last few thousand years, but the fear now is that it might occur much more frequently due to warming sea and air temperatures.
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