The Wilkins Ice Shelf has been cracking in new places recently and images released by the European Space Agency show that it will probably very soon break off entirely. A 62 square mile piece broke off in May 2008.
Angelika Humbert of Muenster University stated, “During the last year the ice shelf has lost about 1800 square kilometers (694 square miles), or about 14 percent of its size.” The Wilkins Ice Shelf is currently about the size of Jamaica, though it has already been diminished by about 30 percent.
In January the British Antarctic Survey found that an array of very large ice chunks were breaking off and separating from the area. “The cracks in the Wilkins ice shelf and the chunks of ice that are splitting away from the ice-shelf….they’re kind of shopping mall chunks of ice and some are floating off into the ocean.” About 8 other such ice shelves there have been lost. At least one of them had been intact for approximately 10,000 years. Recent research has indicated that the loss of Antarctic ice shelves could actually shift the axis of the earth.
The Wilkins shelf is held together by a narrower strip of ice that has been thinning and growing weaker due to melting. Reportedly shaped like an hour glass, with the narrowest portion being the connecting bridge for the larger end pieces, the shelf is now estimated to collapse entirely very soon. The narrower part of the shelf has been estimated at 40 km wide down to 500 meters at the thinnest section. In 1950 the narrow connecting strip was 100 km wide.
The disintegration of such enormous masses of ice is thought to be indicative of the power of global warming to cause very disruptive, if not catastrophic change to the natural environment. One measurement that is tied to the loss of the ice shelves is the temperature increase in the area over the last fifty years of 5 degrees Fahrenheit.
Image Credit: National Ice and Snow Data Center
Other Images, Public Domain and NASA
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