One of Antarctica's largest glaciers is in a headlong, self-sustaining retreat that could be irreversible even if the climate turns colder, scientists say.
That's the conclusion of three research teams that have modeled the behavior of the continent's Pine Island Glacier, or PIG, which at 60,000 square miles contains almost 20 percent of the ice flowing from Antarctica into the ocean.
Data collected by satellites and aircraft have revealed the glacier has been thinning and its velocity increasing in recent years, the researchers said.
"You can think of PIG like a ball. It's been kicked and it's just going to keep on rolling for the foreseeable future," Hilmar Gudmundsson from the British Antarctic Survey told the BBC.
The main driver of its movement is not air temperature, the scientists said, but warm ocean waters getting under and eroding the glacier where it leaves the land and becomes a floating ice shelf.