Scientists examining satellite images of one of Greenland’s largest glaciers believe they have found an unexpected new crack in its floating ice shelf that could contribute to a dramatic break in coming years.
The Petermann Glacier, located in the high Arctic at 80 degrees North latitude, is one of the most important outlets by which the Greenland ice sheet extends and flows into the sea. In 2010 and 2012, it lost extremely large pieces, each several times the size of Manhattan, from its ice shelf, which floats on top of the waters of a fjord whose depth exceeds that of the Grand Canyon.
These changes captured the world’s attention — and greatly shrank this floating shelf that stabilizes the glacier by attaching to the walls of the fjord in which it lies. That’s a big deal because Petermann Glacier holds back about a foot of potential sea level rise from the Greenland ice sheet.