BIRTHDAY CANYON, GREENLAND - Itâs a small contributor now, but its surface has started melting in summerâa worrisome sign. The ice sheet contains enough water to raise sea level nearly 25 feet. ... more 
BIRTHDAY CANYON, GREENLAND - Itâs a small contributor now, but its surface has started melting in summerâa worrisome sign. The ice sheet contains enough water to raise sea level nearly 25 feet. (Photograph by James Balog, Extreme Ice Survey/National Geographic) less 
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Yahoo News | Photo By James Balog, Extreme Ice Survey/National Geographic
Thu, Aug 22, 2013 1:00 PM EDT