Reuters: OSLO (Reuters) — An ice bridge holding a vast Antarctic ice shelf in place has shattered and may herald a wider collapse caused by global warming, a scientist said Saturday. “It`s amazing how the ice has ruptured,” said David Vaughan, a glaciologist with the British Antarctic Survey. “Two days ago it was intact,” he said, referring to a satellite image of the Wilkins ice shelf. The satellite picture, by the European Space Agency, showed that a strip of ice about 25 miles long …