"An iceberg twice the size of Manhattan tore off one of Greenland's largest glaciers, illustrating another dramatic change to the warming island.

For several years, scientists had been watching a long crack near the tip of the northerly Petermann Glacier. On Monday, NASA satellites showed it had broken completely, freeing an iceberg measuring 46 square miles.

A massive ice sheet covers about four-fifths of Greenland. Petermann Glacier is mostly on land, but a segment sticks out over water like a frozen tongue, and that's where the break occurred.

Many of Greenland's southern glaciers have been melting at an unusually rapid pace. The Petermann break brings large ice loss much farther north than in the past, said Ted Scambos, lead scientist at the National Snow and Ice Data Center in Boulder, Colorado."

 Read more: http://www.foxnews.com/scitech/2012/07/18/glacier-twice-as-big-as-manhattan-snaps-off-greenland-ice-sheet/#ixzz227alOwY4