A chunk of ice four times the size of Manhattan has calved from Greenland's Petermann Glacier, scientists announced today. The last time the Arctic lost such a large chunk of ice was in 1962. "In the early morning hours of August 5, 2010, an ice island four times the size of Manhattan was born in northern Greenland," said Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware. Satellite imagery of this remote area at 81 degrees north latitude and 61 degrees west longitude, about 620 miles (1,000 kilometers) south of the North Pole, reveals...