Antarctica

According to the National Snow and Ice Data Center, in 2006, Antarctica contained approximately 95 percent of all the world's freshwater resources. While the frigid temperatures keep the surface below freezing temperature, scientists have discovered that the bottoms of the glaciers at the places where land meets the ocean are melting rapidly throughout the entire continent. Rising ocean temperatures due to global warming have been suggested as the cause. Warmer ocean temperatures are also believed to be responsible for the current accelerated thinning and breakup of the multitude of huge, floating ice shelves, which have also caused the accelerated glacial flow toward the ocean.

After the Larsen B Ice Shelf collapsed in 2002, the glaciers nearby have notably accelerated in their flow and are still speeding up. Since the Wordie Ice Shelf broke in 1995, many major ice streams that feed the Larsen A shelf are flowing two to three times faster toward the ocean now. Crane Glacier increased its speed from 5.6 feet/day (1.7m/d) to 10.2 feet/day (3.1m/d) in April through December of 2002, and then to 13.5 feet/day (4.1 m/d) between December 2002 and February 2003—a nearly 250 percent increase in speed. The ice shelf has acted as a barrier, slowing the glacier's flow. This is a concern, because if larger ice shelves should ever collapse—such as the Ross Ice Shelf—it could trigger an outpouring of several glaciers into the ocean.

The interior of Antarctica is receiving an increase of snow accumulation, however. Scientists believe this is because the water that is being evaporated from the warmer ocean water surrounding the continent is condensing and falling as snow on the interior of the continent. Therefore, right now this process is offsetting some of the melting, but scientists do not know how long that will continue.

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