This just in from NASA:
Using data from ICEsat (Ice, Cloud, and land Elevation Satellite) scientists have discovered that warm currents have been rapidly eating away at the undersides of the ice shelves around Antarctica. A study, recently published in the journal Nature found that twenty of the fifty-four ice shelves studied had been subject to this melting. The majority of them are in West Antarctica.
Researchers used a series of 4.5 million height measurements made by a laser mounted on ICESat. They were able to map the changing thickness of the ice using computer models to compensate for snow accumulation and tide heights, giving an accurate depiction of the loss of ice over the period of October, 2003-October, 2008.
The study’s lead author Hamish Pritchard of the British Antarctic Survey in Cambridge, United Kingdom said:
“We can lose an awful lot of ice to the sea without ever having summers warm enough to make the snow on top of the glaciers melt. The oceans can do all the work from below.”
How about five fast facts on ICESat?
1. ICESat was decommissioned on Saturday August 14, 2010 after its primary instrument failed. It was allowed to burn up in the atmosphere after orbital decay.
3. On November 25th 2005 ICESat successfully fired its one billionth laser shot at the Earth’s surface.
4. ICESat’s laser has also been used to measure clouds, mountains and forests all over the Earth.
5. ICESat operated for more than twice the length its original three-year mission.