“It’s amazing how the ice has ruptured,” said David Vaughan, a glaciologist with the British Antarctic Survey. “Two days ago it was intact,” he said, referring to a satellite image of the Wilkins ice shelf.

The shelf has been retreating since the 1990s, but scientists say this is the first time it has lost one of the connections that keeps it in place.

While the break-up will have no impact on sea level, it heightens concerns over the impact of climate change on this part of Antarctica.