Antarctic ice shelf heading toward collapse

One of Antarctica’s largest ice shelves is nearing its breaking point, scientists warn. A colossal crack in the Larsen C ice shelf grew by 18 kilometers during the second half of December, members of the Antarctic research group Project MIDAS reported January 5. The crack is only about 20 kilometers away from reaching Larsen C’s edge and snapping off a Delaware-sized hunk of ice.

Such a breakup could destabilize the ice shelf — similar to the collapse of Larsen B in 2002, scientists with the project forecast in 2015 (SN: 7/25/15, p. 8). Because Larsen C’s ice is floating on the ocean, the breakup won’t directly raise sea levels. But with the ice shelf gone, more glacial ice could slip into the sea unabated and contribute to sea level rise.