Klimaatverandering 47

De Independent bericht:

'Cracking up: Ice turning to water, glaciers on the move - and a planet in peril.

A new study proves it was global warming that sent an Antarctic ice shelf larger than Luxembourg crashing into the ocean. Geoffrey Lean reports.

Nothing else quite like it has happened at any time in the past 10,000 years. In just over a month an entire Antarctic ice shelf, bigger than a small country, disintegrated and disappeared, altering world atlases for ever.
A new study shows that the catastrophic collapse of the Larsen B shelf, four and a half years ago, was man-made, not an "act of God". It is thought to have been the first time that a major disaster has been proved to have been caused by global warming.
Research at the blue-chip British Antarctic Survey in Cambridge, published last week, has identified the causes of "dramatic warming" of the eastern side of the Antarctic peninsula, where the vast, 3,250 sq km expanse of ice used to be. Gareth Marshall, the lead author of the study, says it marks "the first time that anyone has been able to demonstrate a physical process directly linking the break-up of the Larsen ice shelf to human activity".
The research has also linked the collapse to the hole in the Earth's protective ozone layer that opens up over the Antarctic every southern spring. Nasa scientists reported last week that this year's hole, at a massive 10.6m square miles, is bigger than ever.
It was in March 2002 that the ice shelf - thought to have been stable for thousands of years - suddenly gave way. In just over 30 days an unimaginable 500bn tonnes of ice shattered into tens of thousands of icebergs, drifting in the Weddell Sea. This one event dumped more ice into the Southern Ocean that surrounds Antarctica than all the icebergs of the past 50 years combined. "This is staggering", said the British Antarctic Survey's Dr David Vaughan at the time. "It fell over like a wall and has broken as if into hundreds of thousands of bricks."'

Lees verder: http://news.independent.co.uk/environment/article1919117.ece