Iceberg breaks off from Greenland's Petermann Glacier
July 20 , 2012
An iceberg twice the size of Manhattan has broken away from the Petermann Glacier in Greenland.
Images from a NASA satellite show the island breaking off from a floating river of ice called an ice tongue, which extends at the end of the glacier.
In 2010 an ice island measuring 100 square miles broke off the same glacier.
The process leads to the creation of icebergs, also known as calving, and is a natural process that affects all glaciers.
Calving is not expected have an impact on sea levels as the ice was already floating.
In recent years, scientists have raised concerns over the Greenland ice shelf, saying that it is thinning due to warmer temperatures.
Climate change is not the sole reason for the events such as this.
However, experts have expressed their surprise at the extent of change to the Petermann Glacier.