"Glaciers across the globe are continuing to melt so fast that many will disappear by the middle of this century, the World Glacier Monitoring Service (WGMS) said today.
This 2008 picture shows a view of the Lirung Glacier in the Lantang Valley, northwest of Kathmandu. (AFP/File/Sam Taylor) The announcement of the latest annual results from monitoring in nine mountain ranges on four continents comes as doubts have been cast on how much climate scientists have exaggerated the problem of glacier melt, which is seen as a leading indicator of how much the planet is heating up.
Last week the head of the Intergovernmental Panel on Climate Change (IPCC) apologised for "a paragraph" in its four-volume 2007 report which warned there was a "very high" risk that the Himalayan glaciers, on which at least half a billion of the world's poorest people depend for water, would disappear by 2035.
However the director of the WGMS, Professor Wilfried Haeberli, said the latest global results indicated most glaciers were continuing to melt at historically high rates.
"The melting goes on," said Haeberli. "It's less extreme than in years
but what's really important is the trend of 10 years or so, and that shows an unbroken acceleration in melting."
Haeberli also repeated his warning that many glaciers are set to disappear in the next few decades, due to an expected continuation in the rise of global average temperatures. The most vulnerable glaciers were those in lower mountain ranges like the Alps and the Pyrenees in Europe, in Africa, parts of the Andes in South and Central America, and the Rockies in North America, said Haeberli.
"We are on the path of the highest scenario in reality, but if you take a medium scenario in the Alps about 70% will be gone by the middle of the century, and mountain ranges like the Pyrenees may be completely ice-free."
Glaciers at much higher altitudes - particularly in the Himalayas and Alaska, where it was colder and global warming could increase snowfall - could grow in the short term and were likely to last "centuries", said Haeberli. "But even for the large glaciers, for a realistic scenario, it's centuries, not millennia, and not many centuries," he added.
The WGMS records data for nearly 100 of the world's approximately 160,000 glaciers, including 30 "reference" glaciers, with data going back to at least 1980. Scientists also use methods from geology to photos and travel journals and other data to estimate glacier sizes further back in history.
The latest preliminary figures for 2007-08 show the average reduction in thickness across all the 96 glaciers was nearly half a metre, and since 1980 they have collectively lost an average of 13m thickness.
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http://www.commondreams.org/headline/2010/01/26-5
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