Wednesday, January 27, 2010

Yes Virginia, the Glaciers are Melting


by Bonnie Alter, London on 01.27.10
glaciers melting photo
Images by B.Alter. Perito Moreno glacier in Patagonia

The World Glacier Monitoring Service has jumped into the controversy about whetherthe glaciers are melting. And their answer is an emphatic yes.

In their annual report they confirmed that glaciers across the world are melting so quickly that many will disappear by the middle of this century. Some in a few decades. The most vulnerable are in lower mountain ranges like the Alps and the Pyrenees in Europe, in Africa, parts of the Andes in South America and the Rockies in North America.


tour boat patagonia photo

The annual update on the state of the glaciers confirms that most are continuing to melt at historically high rates. The director of the World Glacier Monitoring Services (WGMS) said that the melting was "less extreme than in years [immediately before] but what's really important is the trend of 10 years or so, and that shows an unbroken acceleration in melting. Glaciers at lower levels such as the Alps will be about 70% will be gone by the middle of the century, and mountain ranges like the Pyrenees may be completely ice-free."

However, glaciers at much higher altitudes, such as the Himalayas and Alaska could grow in the short term. That is because it is colder there and global warming could actually increase snowfall. But he said, even for those their life span is still just centuries, " not millennia, and not many centuries."

The WGMS should know. They record date for more than 90 glaciers worldwide; there are about 160,000 glaciers in the world, including 30 considered to be "reference" glaciers, since they have data going back to at least 1980. According to an article in theGuardian, 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. During that year 30 of the 96 glaciers gained in mass.

So the IPCC may have made a boo-boo, but the British government's chief scientific adviser, Professor John Beddington has stated it best in today's Times::

"It's unchallengeable that CO2 traps heat and warms the Earth and that burning fossil fuels shoves billions of tonnes of CO2 into the atmosphere. But where you can get challenges is on the speed of change.

When you get into large-scale climate modelling there are quite substantial uncertainties. On the rate of change and the local effects, there are uncertainties both in terms of empirical evidence and the climate models themselves.

Some people ask why we should act when scientists say they are only 90 per cent certain about the problem. But would you get on a plane that had a 10 per cent chance of crashing?"

upsala glacier photo
Image of Upsala Glacier

This TreeHugger visited the glaciers in Los Glaciares National Park in Patagonia, Argentina last year (hence the family photos) and they are spectacular. The one stable glacier is Perito Moreno--it is 60 metres high above lake water and is still growing. Mistakenly, poor Al Gore used its image in "An Inconvenient Truth" and identified it as a receding one.

The Upsala Glacier is receding the most. Within ten years it will have shrunk by as much as the size that Merino is now. At the moment it is 60 to 80 metres high.

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