During the last several weeks, NASA has been tracking an unprecedented sea-ice fracturing event off the coast of northern Alaska. As this dramatic satellite video shows, hundreds of square miles of ice twisted and crumbled into the Beaufort Sea.
The whole thing started back in late-January when a high-pressure system parked itself above the region, creating warm temperatures and steady southwesterly winds. This fueled the Beaufort Gyre, what NASA says is a wind-driven ocean current that flows clockwise. The gyre pulled the massive ice sheets past Point Barrow, the northern area of Alaska that extends into the Beaufort Sea.
Visualizations of the Arctic often give the impression that the ice cap is a continuous sheet of stationary, floating ice. In fact, it is a collection of smaller pieces that constantly shift, crack, and grind against one another as they are jostled by winds and ocean currents. Especially during the summer—but even during the height of winter—cracks—or leads—open up between pieces of ice.
By late March, the ice fractures travelled all the way to Canada's Banks Island, a distance of over 600 miles (1,000 km).
Above: Image acquired on February 23, 2013.
It's not unusual for ice-fracturing to occur, but this one covered an extraordinarily large area.