Nature: Recent studies suggest that the Antarctic ice sheet is much less stable than scientists once thought.
Choices that the world makes this century could determine the fate of the massive Antarctic ice sheet. A study published online this week in Nature1 finds that continued growth in greenhouse-gas emissions over the next several decades could trigger an unstoppable collapse of Antarcticas ice -- raising sea levels by more than a metre by 2100 and more than 15 metres by 2500.
That is literally...