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A study last year by the Jet Propulsion Laboratory of the California Institute of Technology showed that, rather than just melting relatively slowly, the ice sheet is showing all the signs of a mechanical break-up as glaciers slip ever faster into the ocean, aided by the "lubricant" of meltwater forming at their base. As the meltwater seeps down it lubricates the bases of the "outlet" glaciers of the ice sheet, causing them to slip down surrounding valleys towards the sea,
Another discovery has been the increase in "glacial earthquakes" caused by the sudden movement of enormous blocks of ice within the ice sheet. The annual number of them recorded in Greenland between 1993 and 2002 was between six and 15. In 2003, seismologists recorded 20 glacial earthquakes. In 2004, they monitored 24 and for the first 10 months of 2005 they recorded 32.
The seismologists also found the glacial earthquakes occurred mainly during the summer months, indicating the movements were indeed associated with rapidly melting ice - normal "tectonic" earthquakes show no such seasonality. Of the 136 glacial quakes analysed in a report published last year, more than a third occurred during July and August.
The creation of Warming Island appears to be entirely consistent with the disintegrating ice sheet, coming about when the glacier bridge linking it to the mainland simply disappeared. It was discovered by Mr Schmitt, a 60-year-old explorer from Berkeley, California, who has known Greenland for 40 years, during a trip he led up the remote coastline.
According to the US Geological Survey: "More islands like this may be discovered if the Greenland Ice Sheet continues to disappear."
A self-governing dependency of Denmark, Greenland is the largest island in the world but is inhabited by only 56,000 people, mainly Inuit. More than 80 per cent of the land surface is covered by the ice sheet
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