An ice bridge which had held a vast Antarctic ice shelf in place for hundreds of years has at least shattered, and may herald a wider collapse linked to global warming.
A satellite picture shows that a 40km long strip of ice believed to pin the Wilkins Ice Shelf in place has snapped at its narrowest point, off the Antarctic Peninsula.
The loss of the ice bridge, which was almost 100km wide in 1950, could allow ocean currents to wash away more of the shelf.
Temperatures on the Antarctic Peninsula have risen by up to about 3 degrees Celsius in the past 50 years, the fastest rate of warming in the Southern Hemisphere.
Nine other shelves have receded or collapsed around the Antarctic Peninsula in the past 50 years.
