West Antarctic ice sheet collapse 'unstoppable': NASA
By Kerry Sheridan, AFP
May 14, 2014, 12:08 am TWN
WASHINGTON -- Ice is melting in the western Antarctic at an “unstoppable” pace, scientists said Monday, warning that the discovery holds major consequences for global sea level rise in the coming decades.
The speedy melting means that prior calculations of sea level rise worldwide made by the Intergovernmental Panel on Climate Change will have to be adjusted upward, scientists told reporters.
“A large sector of the West Antarctic ice sheet has gone into a state of irreversible retreat. It has passed the point of no return,” said Eric Rignot, professor of Earth system science at the University of California Irvine.
“The retreat of ice is unstoppable,” he said, noting that surveys have shown there is no large hill at the back of these glaciers that could hold back the melting ice.
Scientists have been warning about this so-called weak underbelly of western Antarctic for decades, but only since the 1990s have scientists been able to gather detailed information on this remote area.
The results are included in a pair of published studies that document observational changes in the Antarctic in recent years, and predict the future behavior of the melting ice through computer models.
“This retreat will have major consequences for sea level rise worldwide,” Rignot added, anticipating the melting will take place largely in the next two centuries.
“It will raise sea level by 1.2 meters or four feet,” said Rignot, whose paper appears in the peer-reviewed Geophysical Research Letters, a journal of the American Geophysical Union.
Melting over Hundreds of Years
Rignot, a glaciologist at NASA's Jet Propulsion Laboratory, said his study compiled data from satellites, airplanes, ships and ground surveys in the west Antarctic ice sheet.