Huge iceberg breaks off Antarctic shelf close to UK’s Halley Research Station

Such a large "calving" event is considered rare

Credit: Screen shot

An iceberg nearly the size of London has broken off Antarctica close to the UK’s Halley Research Station.

The 470 square mile iceberg’s break from the Brunt Ice Shelf was confirmed by surface instruments on Friday. 

It will now be monitored remotely because of the risk it could pose in future to shipping.

"Although the breaking off of large parts of Antarctic ice shelves is an entirely normal part of how they work, large calving events such as the one detected at the Brunt Ice Shelf on Friday remain quite rare and exciting," Prof Adrian Luckman of Swansea University told the BBC.

Nobody is currently in the research station, which has been operating in a reduced role since 2017 because of the growing possibility of just such an incident.

The research base, which is run by the British Antarctic Survey, was reportedly just 20km from the rupture line of the calving.   

Three long rifts had been actively developing on the Brunt Ice Shelf over the last five years, Prof Luckman said, with researchers expecting “something spectacular was going to happen.”

The calving is not believed to be linked to climate change but is instead part of the natural processes of the ice shelf.

In 2017 an even larger iceberg, A-68, broke away from the Larsen C ice shelf on the Antarctic Peninsula, which has been impacted by climate change. 

That iceberg, which initially measured 2200 square miles, threatened to ground itself off South Georgia late last year in what could have been a disaster for local wildlife.

In February 2017, the modules of the Halley Research Station were towed 14 miles inland because the emergence of a large crack had left it at risk of drifting out to sea on an iceberg.

However, the development of a separate large fissure 11 miles from its new location had already prompted the British Antarctic Survey to mothball the base for the winter, a practice it has continued in subsequent years.

The current base is actually the sixth Halley Research Station, which officially opened in 2013. Halley I operated from 1956 to 1968.