ALBERT

Description: Updated knowledge about the glacier extent and characteristics in the Himalaya cannot be overemphasised. Availability of precise glacier inventories in the latitudinally diverse western Himalayan region is particularly crucial. In this study we have created an inventory of the Suru sub-basin, western Himalaya for year 2017 using Landsat OLI data. Changes in glacier parameters have also been monitored from 1971 to 2017 using temporal satellite remote sensing data and limited field observations. Inventory data shows that the sub-basin has 252 glaciers covering 11% of the basin, having an average slope of 25 ±6° and dominantly north orientation. The average snow line altitude (SLA) of the basin is 5011 ±54 masl with smaller (47%) and cleaner (43%) glaciers occupying the bulk area. Longterm climate data (1901-2017) shows an increase in the mean annual temperature (Tmin & Tmax) by 0.77 ºC (0.25 & 1.3 ºC) in the sub-basin, driving the overall glacier variability in the region. Temporal analysis reveals a glacier shrinkage of ~6 ±0.02 %, an average rate of 4.3 ±1.02 ma-1, debris increase of 62% and 22 ±60 m SLA rise in past 46 years. This confirms their transitional response between the Karakoram and the Greater Himalayan Range (GHR) glaciers. Besides, glaciers in the sub-basin occupy two major ranges, i.e., GHR and Ladakh range (LR) and experience local climate variability, with the GHR glaciers exhibiting a warmer and wetter climate as compared to the LR glaciers. This variability manifestes itself in the varied response of GHR and LR glaciers. While the GHR glaciers exhibit an overall rise in SLA (GHR: 49 ±69 m; LR: decrease by 18 ±50 m), the LR glaciers have deglaciated more (LR: 7 %; GHR: 6 %) with an enhanced accumulation of debris cover (LR: 73%; GHR: 59 %). Inferences from this study reveal prevalence of glacier disintegration and overall degeneration, transition of clean ice to partially debris covered glaciers, local climate variability and non-climatic (topographic and morphometric) factor induced heterogeinty in glacier response as the major processes operatives in this region.