NASA released new data today showing that the high altitude regions of Greenland are melting at 150% faster than the 20 year average. The amount of snow that has melted this year over Greenland could cover the surface size of the U.S. more than twice.
The ice sheet covering Greenland is a mass so big it would raise sea levels by 20 feet if it vanished.
Marco Tedesco, a research scientist at the Joint Center for Earth Systems Technology, cooperatively managed by NASA's Goddard Space Flight Center in Greenbelt, Md., and the University of Maryland at Baltimore County, used satellite data to compare average snow melting from 1988-2006 with what has taken place this summer.
“When snow melts at those high altitudes and then refreezes, it can absorb up to four times more energy than fresh, unthawed snow,” said Tedesco. “This can affect Earth's energy budget by changing how much radiation from the sun is absorbed by the Earth versus that reflected back into the atmosphere. Refrozen snow can also alter the snow density, thickness and snow-water content.” Tedesco's findings were published Sept. 25 in the American Geophysical Union's Eos newspaper.