Mass Balance Estimation Using Geodetic Method for Glaciers in Baspa Basin, Western Himalaya

Himalayan glaciers, which contribute to water security for almost 1.3 billion people in Asia, are now under threat due to climate change. Assessment of glacier mass balance changes is crucial to determine the implications of climate change, but in situ measurements are limited due to rugged terrain and harsh climate of the Himalaya. Remote sensing-based geodetic method is therefore important for studying the evolution of Himalayan glaciers at a large scale. In this study, the mass balance of glaciers located in Baspa basin (Western Himalaya) is estimated for a period of 11 years between 2000 and 2011, using geodetic method. Out of 89 glaciers in the basin, 42 glaciers (greater than 1 km²) covering an area of ~72% (215 km²) of the total glaciated area were selected for the study. A mean thinning of ~50 ± 11 m and mean accumulation of ~35 ± 11 m was observed during the study period, with the cumulative mass balance varying between -36.9 ± 1.98 and 6.47 ± 1.98 m.w.e. A mean annual mass loss of -1.09 ± 0.32 m.w.e.a^-1 was observed for the entire basin, suggesting that the glaciers in Baspa basin are losing mass at higher rate compared to the glaciers in central and eastern Himalayas. This study demonstrates the utility of geodetic method to estimate mass balance of glaciers at basin scale, which will be useful to assess future changes in glacial extent and stream run-off.