Satellite images show that a large hunk of Antarctica's Wilkins Ice Shelf has started to collapse in a fast-warming region of the continent.
Satellite images from Nasa showing Antarctica's Wilkins Ice Shelf as it begins to break up
The area of collapse measured about 415 square kilometres of the Wilkins Ice Shelf, according to satellite imagery from the University of Colorado's National Snow and Ice Data Centre.
The Wilkins Ice Shelf is a broad sheet of permanent floating ice that spans about 13,000 square kilometres and is located on the southwest Antarctic Peninsula about 1,600 kilometres south of South America.
"Block after block of ice is just tumbling and crumbling into the ocean," Ted Scambos, lead scientist at the National Snow and Ice Data Centre, said.
"The shelf is not just cracking off and a piece goes drifting away, but totally shattering. These kinds of events, we don't see them very often. But we want to understand them better because these are the things that lead to a complete loss of the ice shelf," Mr Scambos added.
He said a large part of the ice shelf is now supported by only a thin strip of ice. This last "ice buttress" could collapse and about half the total ice shelf area could be lost in the next few years.
British Antarctic Survey scientist David Vaughan said in a statement: "This shelf is hanging by a thread. One corner of it that's exposed to the ocean is shattering in a pattern that we've seen in a few places over the past 10 or 15 years. In every case, we've eventually concluded that it's a result of climate warming," Scambos added.
Satellite images showing the collapse began on February 28th, as a large iceberg fell away from the ice shelf's southwestern front leading to a runaway disintegration of the shelf interior.
The ice shelf has been in place for at least a few hundred years, but warm air and exposure to ocean waves are causing a breakup. In the past half century, the Antarctic Peninsula has witnessed a warming as fast as anywhere on the planet, according to scientists.