While there is speculation and numerical estimates about what might happen to Antarctica's nation-sized Ross Ice Shelf in a warming climate, oceanographers have a good idea of what happened to a 100,000-square-mile section within 1,500 years after the last Ice Age ended.
The Ross Ice Shelf is a vast floating extension of the West Antarctic Ice Sheet, about the size of France, and the world's largest ice shelf. But it was once much larger, extending farther north and covering the entire Ross Sea. The present Ross Ice Shelf is about 500 miles wide and several hundred feet thick. Because the ice shelf is already floating, its breakup and melting would not pose a risk of raising global sea level.