The Greenland ice sheet is accelerating as it flows toward the ocean, and the unique markings visible in this photograph
are one piece of evidence demonstrating its rapid movement. Captured as part of NASA’s Operation IceBridge, which is wrapping up its seventh season of Arctic observations, this image details heavy crevassing near the coast of Melville Bay in northwestern Greenland. These fissures are essentially stretch marks on the ice, NASA researchers say. Ice sheets in Greenland and Antarctica are losing mass at an unprecedented rate of 500 cubic kilometers per year — enough ice to cover the Chicago metropolitan area with a layer of ice 600 meters thick — according to one recent report.