"Ohio State University (OSU) researchers monitoring daily satellite images of Greenland’s glaciers have discovered break-ups at the Petermann and Jakobshavn glaciers’s—two of the country’s largest—in the last month. They expect that part of what is the Northern hemisphere’s longest floating glacier will continue to disintegrate within the next year.
Petermann has a floating section of ice 10 miles (16 kilometers) wide and 50 miles (80.4 kilometers) long which covers 500 square miles (1,295 square kilometers). An 11 mi2 (29 km2) piece of the Petermann Glacier in northern Greenland broke away between 10 to 24 July. The loss to that glacier is equal to half the size of Manhattan Island. The last major ice loss to Petermann occurred when the glacier lost 33 square miles (86 square kilometers) of floating ice between 2000 and 2001.
Jason Box, an associate professor of geography at Ohio State, and his colleagues, graduate students Russell Benson and David Decker, all with the Byrd Polar Research Center, also identified what appears to be a massive crack further back from the margin of the Petermann Glacier. That crack may signal an imminent and much larger breakup.
“If the Petermann glacier breaks up back to the upstream rift, the loss would be as much as 60 square miles (160 square kilometers),” Box said, representing a loss of one-third of the Petermann tongue."