Greenland's Vanishing Ice Sheet is Melting Faster Than Previously Thought (VIDEO)

Most people are aware that the Greenland Ice Sheet is melting. Yet exactly how fast that melting is occurring has been up for debate. Now, a new study reveals exactly how little we understand this massive expanse of ice, and shows that it may be melting far more quickly than scientists first estimated.

The Greenland Ice Sheet is the second-largest body of ice on Earth. It covers an area about five times the size of New York State and Kansas combined. In it melted completely, oceans could rise by as much as 20 feet.

The melting ice, though, isn't occurring simplistically. The ice sheet both melts and calves ice into the ocean. In order to better understand ice loss, the researchers developed a computational technique called Surface Elevation Reconstruction And Change detection. They fused together data from NASA satellites and aerial missions. In the end, they found that the Greenland Ice Sheet lost about 243 gigatons of ice annually from 2003 to 2009. That's about 277 cubic kilometers of ice per year.

More importantly, researchers found that glaciers don't just gradually lose mass when the temperature rises. In fact, some of Greenland's glaciers thickened even when the temperature rose. Others exhibited accelerated thinning, and some displayed both thinning and thickening with sudden reversals. That's why scientists divided Greenland's 242 glaciers into seven major groups based on their behavior. This, in turn, allowed the scientists to pick out examples of glaciers that were representative of the whole.

"There are 242 outlet glaciers wider than 1.5 km on the Greenland Ice Sheet, and what we see is that their behavior is complex in space and time," said Beata Csatho, one of the researchers, in a news release. "The local climate and geological conditions, the local hydrology-all of these factors have an effect. The current models do not address this complexity."

The findings reveal that the models of today don't accurately predict ice loss. Instead, the new efforts reveal that the ice sheet could lose ice faster in the future than today's simulations suggest. This, in turn, tells scientists a bit more about predictions for future climate change and sea level rise.

The findings are published in the journal Proceedings of the National Academy of Sciences.

Want to learn more? Check out the video below, courtesy of YouTube.

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