Scientists travel to world's 'most important' glacier

Climate scientists have spent five weeks travelling to the "most important" ice sheet in the world.

It's in Antarctica and is called the 'doomsday' sheet because it's melting so quickly.

As global temperatures rise, climate scientists are asking themselves what will happen if this ice melts completely?

The BBC's Chief Environment Correspondent, Justin Rowlatt, travelled there and spent time finding out about the work that's been going on.