A BRITISH research station based on a floating ice shelf in Antarctica is to close for winter amid safety concerns after a 25-mile crack opened up in the ice.

The Halley VI research centre, run by the British Antarctic Survey (BAS), will shut down between March and November as a “precautionary measure” due to the opening up what has become known as the Hallowe’en Crack.

Aerial pictures emerged last month showing the chasm 10 miles north of the station, which is based on the Brunt Ice Shelf.

It presents a “complex glaciological picture” which means scientists are unable to predict what will happen to the area during the Antarctic winter.

There is no immediate risk to the 88 people currently working at the station but it would be “extremely difficult” to evacuate during the winter if the ice shelf fractured, BAS said.

Captain Tim Stockings, director of operations, said: “We want to do the right thing for our people. Bringing them home for winter is a prudent precaution given the changes that our glaciologists have seen in the ice shelf in recent months.

“Our goal is to winterise the station and leave it ready for reoccupation as soon as possible after the Antarctic winter.”

The Halley VI station was due to be occupied by 16 staff over the winter months.

The centre is currently being relocated inland to a safer part of the ice shelf – 14 miles from its present site – with the project expected to be completed by early March.

During the winter months, the staff would watch over experiments.

However, BAS now has to decide if any of those experiments can be left running autonomously, or whether it is better to just shut everything down.

Scientists have put sensors on either side of the Hallowe’en Crack so that they can monitor its status.

Cpt Stockings said: “Obviously, we’ll seek to get out of those whatever we can; we’ll also be using satellite imagery over the winter as well. Then, next season we’ll send a team in to re-open the station, verify the measurements from our instruments and take the situation from there.

“But I should say, we are committed to our presence in that part of the British Antarctic Territory and to the science we do there. Absolutely.

“We’ve spent a long time finding the new site for Halley VI and of itself this site isn’t directly at risk – it’s just the unpredictability of the whole area.”