Himalayan glaciers are actually advancing rather than retreating, claims the first major study since a controversial UN report said they would be melted within quarter of a century.
The Telegraph 1/27/11
By Dean Nelson and Richard Alleyne
Researchers have discovered that contrary to popular belief half of the ice flows in the Karakoram range of the mountains are actually growing rather than shrinking.
The discovery adds a new twist to the row over whether global warming is causing the world's highest mountain range to lose its ice cover.
It further challenges claims made in a 2007 report by the UN's Intergovernmental Panel on Climate Change that the glaciers would be gone by 2035.
Although the head of the panel Dr Rajendra Pachauri later admitted the claim was an error gleaned from unchecked research, he maintained that global warming was melting the glaciers at "a rapid rate", threatening floods throughout north India.
The new study by scientists at the Universities of California and Potsdam has found that half of the glaciers in the Karakoram range, in the northwestern Himlaya, are in fact advancing and that global warming is not the deciding factor in whether a glacier survives or melts.
Dr Bodo Bookhagen, Dirk Scherler and Manfred Strecker studied 286 glaciers between the Hindu Kush on the Afghan-Pakistan border to Bhutan, taking in six areas.
Their report, published in the journal Nature Geoscience, found the key factor affecting their advance or retreat is the amount of debris – rocks and mud – strewn on their surface, not the general nature of climate change.
Glaciers surrounded by high mountains and covered with more than two centimetres of debris are protected from melting.
Debris-covered glaciers are common in the rugged central Himalaya, but they are almost absent in subdued landscapes on the Tibetan Plateau, where retreat rates are higher.
In contrast, more than 50 per cent of observed glaciers in the Karakoram region in the northwestern Himalaya are advancing or stable.
"Our study shows that there is no uniform response of Himalayan glaciers to climate change and highlights the importance of debris cover for understanding glacier retreat, an effect that has so far been neglected in predictions of future water availability or global sea level," the authors concluded.
Dr Bookhagen said their report had shown "there is no stereotypical Himalayan glacier" in contrast to the UN's climate change report which, he said, "lumps all Himalayan glaciers together."
Dr Pachauri, head of the Nobel prize-winning UN Intergovernmental Panel on Climate Change, has remained silent on the matter since he was forced to admit his report's claim that the Himalayan glaciers would melt by 2035 was an error and had not been sourced from a peer-reviewed scientific journal. It came from a World Wildlife Fund report.
He angered India's environment minister and the country's leading glaciologist when he attacked those who questioned his claim as purveyors of "voodoo science".
The environment Minister Jairam Ramesh had cited research indicating some Himalayan glaciers were advancing in the face of the UN's claim.
Abstract located here:
Spatially variable response of Himalayan glaciers to climate change affected by debris cover
Authors: Dirk Scherler, Bodo Bookhagen, Manfred R. Strecker
Controversy about the current state and future evolution of Himalayan glaciers has been stirred up by erroneous statements in the fourth report by the Intergovernmental Panel on Climate Change1, 2. Variable retreat rates3, 4, 5, 6 and a paucity of glacial mass-balance data7, 8 make it difficult to develop a coherent picture of regional climate-change impacts in the region. Here, we report remotely-sensed frontal changes and surface velocities from glaciers in the greater Himalaya between 2000 and 2008 that provide evidence for strong spatial variations in glacier behaviour which are linked to topography and climate. More than 65% of the monsoon-influenced glaciers that we observed are retreating, but heavily debris-covered glaciers with stagnant low-gradient terminus regions typically have stable fronts. Debris-covered glaciers are common in the rugged central Himalaya, but they are almost absent in subdued landscapes on the Tibetan Plateau, where retreat rates are higher. In contrast, more than 50% of observed glaciers in the westerlies-influenced Karakoram region in the northwestern Himalaya are advancing or stable. Our study shows that there is no uniform response of Himalayan glaciers to climate change and highlights the importance of debris cover for understanding glacier retreat, an effect that has so far been neglected in predictions of future water availability9, 10 or global sea level11.