WASHINGTON, Aug. 11 (UPI) -- U.S. scientists say the entire ice mass of Greenland could disappear if temperatures rise by as little as 4 degrees F, with severe worldwide consequences.
Richard Alley, a geosciences professor at Pennsylvania State University, said Greenland shed its largest chunk of ice in nearly half a century last week and faces an even grimmer future, Britain's The Guardian newspaper said.
"Sometime in the next decade we may pass that tipping point which would put us warmer than temperatures that Greenland can survive," Alley told a briefing in Congress, saying a rise in the range of 4 to 12 degrees Fahrenheit would mean the obliteration of Greenland's ice sheet.
The result would be a global sea level rise of 23 feet, Alley warned, causing low-lying cities such as New Orleans to vanish.
"What is going on in the Arctic now is the biggest and fastest thing that nature has ever done," he said.
Ice mass is disappearing in Greenland at an increasing rate, dumping more icebergs into the ocean because of warming temperatures, he said.
Robert Bindschadler, a research scientist at the University of Maryland, warned of an irreversible "tipping" point.
"While we don't believe it is possible to lose an ice sheet within a decade, we do believe it is possible to reach a tipping point in a few decades in which we would lose the ice sheet in a century," he told the congressional briefing.
