NASA flies over Antarctica to measure icemelt

The DC-8 left Punta Arenas, Chile, on a mission to fly as low as 1,000 feet (300 meters) over Antarctica. Like the NASA satellite that has provided shocking data on how quickly Antarctic ice is disappearing, this plane will measure snow cover and ice thickness. But it also has equipment that will enable scientists to see under the ice shelves, measuring the water below.

The goal is to understand just how warm ocean currents may be pulling the ice sheets seaward, melting their undersides. These ice sheets are rapidly collapsing - as fast as nine meters (27 feet) a year according to a study published in the journal Nature last month. If they disappear, far greater ice masses that lie on Antarctic bedrock could then melt into the sea, submerging coastal communities around the globe.

Until now, the U.S. National Aeronautic and Space Administration has used satellites to track the impact of climate change in the Antarctic, but the satellite will be phased out at year's end. Friday's flight is the first of many planned as part of Operation Ice Bridge, to bridge the gap in data that would otherwise result before the next satellite goes up in 2015.

Investigators from the Columbia University's Lamont-Doherty Earth Observatory, the University of Washington and the University of Kansas also are on board for the 11-hour flights, running their own sets of instruments.

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On the Net:

NASA Ice Bridge blog: http://blogs.nasa.gov/cm/blog/icebridge

Ice Bridge Twitter: http://twitter.com/IceBridge

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