Mass Balance of Glaciers in Bhaga Basin, Western Himalaya: A Geospatial and Temperature-Weighted AAR based Model Approach

Several recent studies carried out in the Himalayan region suggest enhanced receding rate of glaciers during the last two decades. Glacier health can be assessed by monitoring various glacier dynamics that includes mass balance, accumulation area ratio (AAR), equilibrium line altitude (ELA), etc. Here AAR, ELA and regressed mass balance for nine glaciers of the Bhaga basin, Western Himalaya during 2008–18 are presented using high resolution Sentinel 2 (10 m) and Landsat 7/8 (30 m) data with improved AAR and degree day/temperature index (DD/TI) model. Transient snow line (TSL) and AAR derived from the model were used in different regression equations to estimate the mass balance in both glacier and basin scale. In situ precipitation and temperature data obtained from the automatic weather station located at Keylong, Himachal Pradesh were used in this model based approach. Overall, the data reveal that most of the glaciers have experienced critical thinning and lost huge ice mass in the range –6.07 m.w.e. to –9.06 m.w.e.