A rapidly melting glacier atop East Antarctica is on track to lift oceans at least two metres, and could soon pass a "tipping point" of no return, researchers said Wednesday. To date, scientists have mostly worried about the Greenland and West Antarctic ice sheets as dangerous drivers of sea level rise. "I predict that before the end of the century the great global cities of our planet near the sea will have two- or three-metre (6.5 - 10 feet) high sea defences all around them," said Martin Siegert, co-director of the Grantham Institute and Department of Earth Science and Engineering at Imperial College London, and the study's senior author.
