A massive 25-mile-long Antarctic ice bridge between a Jamaica-sized ice shelf and an island has broken in what scientists are calling an alarming sign of runaway global warming, the BBC reports. It was the first time the shelf, which has been retreating for years, has lost a link holding it in place. Scientists believe it may be a sign that the shelf is ready to peel away entirely. “Two days ago it was intact. We've waited a long time to see this,” one told Reuters.