Largest Arctic iceberg in four decades off Greenland

A massive sheet of ice has separated from the Petermann Glacier in northern Greenland, forming the largest Arctic iceberg in about four decades.

The island of ice measuring 260 sq km (100 sq miles) was spotted by a NASA satellite sensor. The massive sheet of ice is roughly more than four times the size of New York's Manhattan Island and is almost about half the height of the Empire State Building in thickness.

Where is Iceberg headed?
The ice island was detected in NASAsatellite images by Trudy Wohlleben of the Canadian Ice Service, on Thursday.

The giant piece of ice may break out into the waters between Greenland and Canada or, as the winter approaches, it may become frozen in place.

“The freshwater stored in this ice island could keep the Delaware or Hudson rivers flowing for more than two years,” University of Delaware researcher Andreas Muenchow said in a statement posted on the school's website. “It could also keep all U.S. public tap water flowing for 120 days.”

An iceberg of such a vast surface area was last seen in the Arctic in 1962.

Muenchow, a professor of physical ocean science and engineering, is studying the Nares Strait between Greenland and Canada, where the iceberg is likely moving. It is currently about 620 miles from the North Pole.

The professor says the ice could block key shipping routes, if it gets stuck in the narrow waterway. Also, there is a possibility that it gets distributed to the Atlantic after breaking up into smaller chunks.

Largest iceberg seen in four decades
Thousands of icebergs emerge from the frozen west coast of Greenland every year. However, the ones as big as this are usually not seen in the Arctic region; they are typical of the Antarctic.

An iceberg of such a vast surface area was last seen in the Arctic in 1962, when a 230-square-mile ice island broke off from the Ward Hunt Ice Shelf. It was also found in the Nares Strait.

Petermann Glacier is the largest in the northern hemisphere. Experts had recently observed some cracks in it, and were expecting it to break-up soon.

During summers, when ice in the glaciers begins to thin down, it cracks up in some places and the chunks separate as icebergs. Global warming has worsened the situation, leading to more and frequent formation of icebergs.

It could not be said if the separation of this chunk from the Petermann Glacier is to be blamed on Global warming.