Even by the standards of Antarctica, there are few places as remote and hostile as Thwaites Glacier. More than 1,000 miles from the nearest research base, battered by storms that can last for weeks, with temperatures that hit -40C in winter, working on the glacier is sometimes compared to working on the moon. Dubbed the “doomsday” glacier, Thwaites, perhaps more than anyother place in the world, holds crucial clues about the future of the planet . Only a handful of people had ever set foot on Thwaites before last year. Now it is the focus of a major research project, led by British and American teams, as scientists race to understand how the glacier – which is the size of Britain and melting very quickly – is changing, and what that means for how much sea levels rise during our lifetimes.

“It is the most vulnerable place in Antarctica,” says Rob Larter, a marine geophysicist and UK principal investigator for the Thwaites Glacier Project at the British Antarctic Survey. He takes a map and points to parts of the deteriorating glacier that have already broken off. “A lot of this is no longer there,” he says. The scientists studying Thwaites go to extreme lengths to carry out their research. Geologist Joanne Johnson spent eight weeks sharing a tent with just one other person in the Thwaites area earlier this year.

“If something goes wrong, you are a very, very long way from help,” says Ms Johnson, a geologist at the British Antarctic Survey. Getting along with your colleague h; crucial for survival. “Although you are in isolation, you are actually not very isolated at all, because you have this person who is with you 24 hours a day.”The extreme version of lockdown, she says, was not too bad.”I really enjoy that kind of world, I enjoy the isolation, and feeling like you are at one with the landscape,” she says. But the situation of Thwaites Glacier is more alarming. “The glacier is changing so fast at present, that we are very concerned that it will drain a lot of ice into the sea,” says Ms Johnson. “It is quite unstable, and you can see that when you fly over it, with loads of crevassing.”