Monitoring of glacial mass balance in the Baspa basin using accumulation area ratio method

Abstract

In the Himalaya, glacier and snow-melt form an important source of water into the North Indian ri vers. However, this source of water is not permanent as glacial dimensions change with climate. One of the important parameters to model future changes in glacial extent is the mass balance. In this communication an attempt has been made to calculate the mass balance for 19 glaciers in Himachal Pradesh using accumulation area ratio (AAR) method. A regression relationship between AAR and specific mass balance was developed using field data from 1982 to 1988 for Shaune Garang glacier and 1976 to 1984 for Gor Garang glacier. Regression analysis suggests good correlation between AAR and specific mass balance with r 2 as 0.80. AAR for 2000 and 2001 was estimated for 19 glaciers in the Baspa basin by systematic weekly analysis of WiFS images of Indian Remote Sensing satellite from May to September. Mass balance was estimated during 2001 and 2002 for 19 gl aciers in the basin, suggesting overall specific mass balance value of – 90 and – 78 cm, respectively. The investigations suggest a loss of 0.2347 km 3 of glacial ice in the last two years. The investigation has shown that four glaciers have no accumulation area, as these are located in lower -altitude zones. These glaciers are expected to face terminal retreat due to lack of formation of new ice. This is likely to pose serious problem of availability of water to many villages located in the Baspa basin.