Mass balance estimation of Mulkila glacier, Western Himalayas, using glacier melt model

One of the main water supplies in Asia is known to be melting water from Himalayan glaciers. One of the most important metrics to analyze and evaluate potential shifts in freshwater supplies from glacier storage is the estimate of mass balance. The present study aims at estimating the glacier mass balance with the help of remote sensing and in situ data for the Mulkila, a benchmark glacier situated in the Bhaga basin of Western Himalayas. The inter-annual difference in the run-off of glaciers is associated with the annual change in glacier mass. To estimate the mass balance of the Mulkila glacier, the current study uses the transient snowline, accumulation area ratio (AAR), and glacier melt model. For 10 consecutive hydrological years from 2009 to 2018, the analysis was conducted using 40 cloud-free Landsat 5/7/8 and Sentinel-2 datasets. Additionally, in situ meteorological weather data for calculating precipitation and changes in temperature were also used. For the period of study, a cumulative mass balance of - 6.66 m.w.e. for 10 years and a mean mass balance of - 0.66 ± 0.27 m.w.e./year were obtained. A negative mass balance obtained for many consecutive hydrological years indicates the effect of climate change and global warming on the glacier ice thinning. This directly affects the regional or local environment and, in the long run, alters water supply. The findings of the present study help in preparing an immediate commitment to curb future warming both at the local and regional scale.