The loss observed by the European Space Agency's CryoSat is considerably more than when the area was last surveyed, they said.
The total is dominated by ice losses from three glaciers flowing into the Amundsen Sea, a release from the Paris headquarters of the ESA said Thursday.
"We find that ice thinning continues to be most pronounced along fast-flowing ice streams of this sector and their tributaries, with thinning rates of between 4 to 8 meters (13 feet to 16 feet) per year near to the grounding lines -- where the ice streams lift up off the land and begin to float out over the ocean -- of the Pine Island, Thwaites and Smith glaciers," Malcolm McMillan from Britain's University of Leeds said.
Ongoing melting of ice sheets that blanket Antarctica and Greenland is a major contributor to global sea-level rise, the researchers said.
The melting of West Antarctica ice sheets caused global sea levels to rise by 0.28 mm each year between 2005 and 2010, scientists had previously estimated, but the latest data from CryoSat suggests the sea level contribution from this area is now 15 percent higher.
Launched in 2010, the satellite carries a radar altimeter that can measure the surface height variation of ice in high resolution, allowing accurate calculations of its volume.
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