Patagonia’s big melt ’sign of global warming’

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GREENPEACE International claims new pictures it has taken of the Patagonian glaciers show the extent to which the vast tracts of ice in South America have receded because of climate change. The glaciers and icefields, which cover more than 17,000 square kilometres across Chile and Argentina, are disappearing at a rate of 42 cubic kilometres a year, the fastest glacial recession in the world.

The most recent pictures of the Upsala glacier, in Argentina, were taken last month by a Greenpeace research team that toured the region gathering evidence on the accelerating disappearance of some of the world’s most famous icefields.

The team found that compared with photos taken from the same outlook in
1928, the glaciers had significantly thinned and retreated several kilometres.

Scientists believe climate change, caused by greenhouse gases trapped in the Earth’s atmosphere, leading to higher sea and land temperatures, is behind the Patagonian glacial melt.

But the melt has also accelerated because, as “calving” glaciers that discharge icebergs into lakes and oceans, the Patagonian glaciers are more susceptible to climate change than those that end on land and melt at their front edge.

Greenpeace International climate spokesman and tour member Jorgis Thijssen said yesterday that the rapid melting of the world’s glaciers, considered to be Earth’s natural thermometers, was a disturbing indication of the increasing impact of global warming.

Mr Thijssen said the degree of annual glacial melting in Patagonia alone was enough to fill a large football stadium the size of Wembley or the Melbourne Cricket Ground about 10,000 times over.

While that did not affect local communities’ freshwater supplies, as it had in regions such as the Himalayas, it would eventually damage local tourism.

In the meantime, it had already hurt the fishing industry. “Now, because
(the glacier is) receding so fast, fishermen can fish only two months, rather than six, because there’s so much ice in the water,” Mr Thijssen said.

“Glaciers advance and recede all the time but the cycle is usually over
10,000 years, and the rate at which it is currently melting cannot be explained by natural glacial.”

A joint study by NASA and Chile’s National Centre for Scientific Studies recently found that glacial melts worldwide were now responsible for about 10 per cent of the rise in sea levels globally.

The latest report by the Intergovernmental Panel on Climate Change, a UN-organised body of more than 2500 scientists, has predicted that sea levels will rise by between 15cm and one metre this century.