In this Dec. 17, 2012 photo released by scientist Nancy Bertler, scientists and staff push a sled containing crates of ice they've collected in order to load them on a plane on Roosevelt Island, ... more 
In this Dec. 17, 2012 photo released by scientist Nancy Bertler, scientists and staff push a sled containing crates of ice they've collected in order to load them on a plane on Roosevelt Island, Antarctica. The continent's pristine habitat provides a laboratory for scientists studying the effects of climate change. (AP Photo/Nancy Bertler) less 
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Associated Press | Photo By Nancy Bertler
Sat, Apr 6, 2013 8:20 AM EDT