Himalayan glaciers meltdown: impact on south Asian rivers

HASNAIN, S. I. 2002. Himalayan glaciers meltdown: impact on south Asian rivers. Friend 2002- Regional Hydrology: Bridging the Gap between Research and Practice, 417-423.


Abstract: The Himalaya mountains contain the largest volume of ice outside the polar regions. About 17% of the Himalaya and 37% of Karakoram mountains are covered by glacier ice. The meltwaters from its glaciers form the headwaters of major rivers as the Indus, the Ganges and the Brahmaputra. The discharge of headwater rivers comprises about 70-80% of snow and ice melt. In recent years the summers have been particularly warm as average air temperatures have risen rapidly by more than 1.5°C, increasing the year to year variability of river flow. The majority of Himalayan glaciers are nourished by the precipitation during the summer-monsoon and therefore they are very sensitive to summer air temperature fluctuations. This paper will examine how climate change influences glacier behaviour and the quantity of discharge in rivers draining from glaciated Himalayan basins. A case study of the Dokriani Glacier (Ganga headwaters, India) is presented. 
Key words: glacier mellwater; global climate; south Asian rivers; summer-accumulation glaciers; Dokriani Glacier; Ganga; India.