Ice loss across Antarctica increased by 75 percent from 1996 to 2006 and is now nearly as great as that observed in Greenland, according to a new study of satellite data by researchers at NASA and the Universtity of California, Irvine.
The losses have happened primarily in West Antarctica's Pine Island Bay sector and the northern tip of the Antarctic Peninsula. The experts tied the loss to faster glacial flow into the seas, which the researchers noted had warmed in recent years.
The warmer waters erode the floating areas of glaciers, causing them to thin or collapse.
"Changes in Antarctic glacier flow are having a significant, if not dominant, impact on the mass balance of the Antarctic ice sheet," study leader Eric Rignot of NASA's Jet Propulsion Laboratory said in a statement released with the study, which was published in February's issue of Nature Geoscience.
The team noted that while ice loss in 1996 had raised global sea level by .01 inches, in 2006 the level was .02 inches.
Using 15 years of satellite data, the team measured ice flowing out of Antarctica's drainage basins over 85 percent of its coastline.
The new results are about 20 percent higher over a comparable time frame than those of a NASA study of Antarctic mass balance last March.
"Our new results emphasize the vital importance of continuing to monitor Antarctica using a variety of remote sensing techniques to determine how this trend will continue," Rignot said. "Large uncertainties remain in predicting Antarctica's future contribution to sea level rise. Ice sheets are responding faster to climate warming than anticipated."
While the study found the greatest ice loss on the west side of Antarctica, Rignot warned the entire continent — which is bigger than the continental United States — could be at risk.
"Even in East Antarctica, where we find ice mass to be in near balance, ice loss is detected in its potentially unstable marine sectors, warranting closer study," he said.