Ice shelf in Antarctica has shrunk by 85%
Images taken by a satellite show that the Larsen B ice shelf decreased from 4,373 square miles in 1995 to only 634 miles today.
Fri, Apr 27, 2012 at 10:44 AM
ICE SHELF: Larsen B is one of three ice shelves that run from north to south along the eastern side of the peninsula, the tongue of land that projects towards South America. (Photo: Martin Bureau/AFP)
A vast ice shelf in the Antarctic peninsula, a hotspot for global warming, has shrunk by 85 percent in 17 years, the European Space Agency said on Thursday.
Images taken by its Envisat satellite show that the so-called Larsen B ice shelf decreased from 4,373 square miles in 1995, an area about the size of the Gulf state of Qatar, to only 634 miles today.
Larsen B is one of three ice shelves that run from north to south along the eastern side of the peninsula, the tongue of land that projects towards South America.
From 1995 to 2002, Larsen B experienced several calving events in which parts of the shelf broke away. It had a major breakup in 2002 when half of the remainder disintegrated.
Larsen A broke up in January 1995.
"Larsen C so far has been stable in area, but satellite observations have shown thinning and an increasing duration of melt events in summer," the agency said in a press release.
Ice shelves are thick floating mats of ice, attached to the shore, that are created by the runoff into the sea from glaciers.
Scientists say they are extremely sensitive to changes in atmospheric temperature and can be hollowed out from below by warmer ocean currents.
The northern Antarctic peninsula has been subject to atmospheric warming about 4.5 degrees Fahrenheit over the last 50 years, a figure that is several times greater than the global average.
Ice shelves are not the same as ice sheets, the vast blanket of frozen water that covers Antarctica.
If these melted, even partially, they would drive up sea levels, threatening small island states and coastal cities. But the scientific evidence is that the icesheets so far are stable.
"These observations are very relevant for measuring the future behaviour of the much larger ice masses of West Antarctica if warming spreads further south," ESA quoted Helmut Rott, a professor at the University of Innsbruck in Austria, as saying.
Copyright 2012 AFP Global Edition