Some truly chilling news came from Antarctica this week as an iceberg eight times the size of Manhattan broke off from the continent. In October 2011, NASA scientists noticed that a crack was forming in the 200 to 1200-meter-thick Pine Island Glacier on the west side of the continent. The growing crevice finally reached its end this week and calved into the ocean. The new piece of ice is about 720 square kilometers in area.
The Pine Island glacier was the fastest flowing in the Western Antarctic at a rate of 4km each year. Its speed was aided in part by alterations in wind direction over the region that brought warm seawater underneath the main ice shelf, melting it from below. Due to the fact that much of Antarctica is below sea level, the geography creates a danger that the rest of the shelf will start to slide.
Were the West Antarctic ice shield to make its way into the ocean, it could contribute to a 3.3 meter rise in global sea levels. If the Pine Island glacier itself were to melt, which is possible if the nearby Thwaite’s Glacier also gives way, it could translate to a half meter of sea level rise.
When asked whether or not the recent activity in Antarctica was due to climate change, Professor Angelika Humbert from the Alfred Wegener Institute was cautious to establish a link. “The creation of cracks in the shelf ice and the development of new icebergs are natural processes“, she says.
Via Vice Motherboard