India on Monday challenged the internationally accepted view that the Himalayan glaciers were receding due to global warming. The glaciers, although shrinking in volume and constantly showing a retreating front, have not in any way exhibited any abnormal annual retreat of the order that some glaciers in Alaska and Greenland have reported, a state-of-the-art review of Glacial Studies, Glacial Retreat and Climate Change said.Brought out by V.K. Raina, former Deputy Director-General, Geological Survey of India, for the Ministry of Environment and Forests, the discussion paper on the Himalayan glaciers points out that it was premature to make a statement that the glaciers were retreating abnormally because of global warming.The study says a glacier is affected by a range of physical features and a complex interplay of climatic factors, and it is, therefore, unlikely that the snout movement of any glacier can be claimed to be the result of periodic climate variation until many centuries of observations become available.
While glacier movements are primarily due to climate and snowfall, snout movements appear to be peculiar to each glacier, the paper adds.Releasing the documents, Minister of State for Environment and Forests Jairam Ramesh said that while most Himalayan glaciers were retreating, some were advancing as well. This included the Siachen glacier.“Some glaciers are retreating at a declining rate, like the Gangotri, and the overall health of the Himalayan glaciers was poor as the debris cover had reached alarming proportions,” he said, citing the paper.Mr. Ramesh added that there was no conclusive scientific evidence to show that global warming was resulting in the glacial retreats. Contrary to what most believe, there can be no comparison between the Arctic glaciers and the Himalayan glaciers, as the former are at sea-level and the latter at a very high altitude.
According to Mr. Raina, all glaciers under observation in the Himalayan region during the past three decades have shown cumulative negative mass balance (determined by annual snow precipitation). Degradation of the glacier mass has been the highest in Jammu and Kashmir, relatively lower in Himachal Pradesh, even less in Uttarakhand, and the lowest in Sikkim — showing a declining trend from the north-west to the north-east.Irrespective on latitudinal difference, glacier melt contributes to about 25-30 per cent of the total discharge of glacier ice, with maximum discharge in mid-July and August.Assuring several steps to study the Himalayan glaciers scientifically and arrive at a final conclusion, Mr. Ramesh said he would bring the discussion paper to the notice of R.K. Pachauri, chief of the Intergovernmental Panel on Climate Change, and other agencies that have warned of doom due to melting glaciers.
The Hindu, November 10th , 2009
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