In the spring and summer of 2012, land- and sea ice thinned in some regions within the Arctic Circle and completely disappeared in others. Satellites watched as a hurricane-force storm hovered over the North Pole, the Northwest Passage was full of open water, and Greenland's Petermann Glacier dropped another city-sized ice cube into the sea. The Arctic Ocean witnessed its lowest area of sea ice since satellite records began in 1979, and nearly the entire surface of Greenland was melting simultaneously for a weekend in July. Some of the phenomena were familiar and natural, if a bit more extreme. Other events lined up with scientists' ideas about how Arctic weather and climate are changing because of warmer ocean and air temperatures and lower albedo (sunlight reflectance).
This time-lapse video shows the calving of an ice island from Greenland's Petermann Glacier and the drifting of the ice down the fjord and southward through Nares Strait. The images were captured between July 9 and September 13, 2012, by NASA's Terra and Aqua earth-observing satellites. This is the second time in three years that a city-sized hunk of ice has ripped off from the glacier.