An ice island four times the size of Manhattan broke off from one of Greenland's two main glaciers, scientists have said, in the biggest such event in the Arctic in nearly 50 years.
The new ice island, which broke off on Thursday, will enter a remote place called the Nares Strait, about 620 miles south of the North Pole between Greenland and Canada.
The ice island has an area of 100 square miles and a thickness up to half the height of the Empire State Building, said Andreas Muenchow, professor of ocean science and engineering at the University of Delaware.
In 2009, a team of scientists supported by the environmental group Greenpeace, observed cracks emerging and they estimated a larger iceberg would soon break away from the Petermann Glacier, one of the two largest remaining ones in Greenland.
Muenchow, said it was hard to judge whether the event occurred due to global warming because records on the sea water around the glacier have only been kept since 2003. The flow of sea water below the glaciers is one of the main causes of ice calvings off Greenland.
Scientists have said the first six months of 2010 have been the hottest globally on record. The El Nino weather pattern has contributed to higher temperatures, but many scientists say elevated levels of man-made greenhouse gases are pushing temperatures higher.