VANCOUVER - Over the course of several weeks this past winter, hundreds of kilometres of ice cracked and crumbled into the ocean north of Alaska.
Scientists with NASA’s Earth Observatory, which captured the fracture using infrared imaging from a satellite, say it’s not unusual for large ice fractures to occur in the Beaufort Sea.
Although sea ice in the Arctic often appears as once giant sheet, the Earth Observatory says it’s actually “a collection of smaller pieces that constantly shift, crack, and grind against one another.”
“A fracturing event in this area is not unusual,” says the U.S. National Snow & Ice Data Center’s Walter Meier — even in winter.
But, this ice crack was more significant because of a high-pressure system that stayed over the area and kept temperatures warm.
A wind-driven ocean current, called the Beaufort Gyre, pulled the ice floes westward past Point Barrow, making the ice appear as though it was fanning out towards Alaska’s northern coast.
By March, the ice fractures spread all the way to the to Canada’s Banks Island — nearly 1,000 kilometres away from the first breaks.
NASA said on Wednesday Arctic Ocean ice was at its lowest level on record last summer, and, on Feb. 28, the maximum winter ice cover reached the fifth lowest in 35 years.