A large chunk of Antarctica's Wilkins Ice Shelf has begun to collapse in what scientists say is further evidence of the toll climate change is taking on the frozen continent.

Satellite images show a large iceberg began breaking away from the ice shelf on February 28, leading to a collapse of 415 square kilometers of the shelf's interior. 

Scientists say a large part of the shelf is now supported by a thin strip of ice.  David Vaughan, a scientist with the British Antarctic Survey, says the ice shelf is "hanging by a thread." 

The Wilkins Ice Shelf is located in the southwest Antarctic Peninsula, near South America.  Because it is a floating sheet of ice, scientists say the break-up will have no impact on sea levels.  The ice shelf is expected to survive until next year, thanks to the coming end of the Antarctic summer season.

Scientists say the Antarctic Peninsula has experienced unprecedented warming over the last five decades.  Several ice shelves have retreated during that time, six of them collapsing completely. 

Vaughan predicted in 1993 that the Wilkins Ice Shelf would be lost within 30 years.