Mapping spatial patterns of glacier elevation changes and mass balance between 2000–2023 across the Karakoram-Himalayan Range

Abstract

Himalayan glaciers are experiencing rapid changes due to ongoing climatic shifts, leading to significant glacier retreat, thinning, and mass loss. These changes are characterized by altered topography, reduced glacier-covered areas, and variable climatic conditions across different regions, resulting in enhanced melt rates and increased vulnerability to glacial hazards. Understanding these distinctive characteristics is crucial for predicting future water resource availability and mitigating climate-induced hazards. In the present study, glacier mass balance was computed by analyzing temporal elevation changes across the entire Karakoram-Himalayan Range from 2000 to 2023. This analysis utilized the Shuttle Radar Topography Mission (SRTM) and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Digital Elevation Model (DEM) datasets from two distinct periods to accurately assess changes in glacier elevation and mass. The study revealed a trend of positive elevation change in the Karakoram region, along with an uneven spatial distribution of elevation changes when moving from Western to Eastern Himalayan glaciers. The Karakoram Range exhibited average mass balance rates of -0.04 ± 0.09 m.w.e./yr, while the Western Himalayas recorded change rates of approximately -0.41 ± 0.24 m.w.e./yr. In contrast, the Central and Eastern Himalayan sectors demonstrated rates of -0.39 ± 0.21 m.w.e./yr and -0.50 ± 0.31 m.w.e./yr, respectively. The results indicate accelerating mass loss in the Western, Central, and Eastern Himalayas, while the Karakoram sector remains relatively stable. Notably, the increasing rate of mass loss in the Eastern Himalayas is particularly alarming. However, mass balance measurements in this study relied upon surface elevation changes and may not accurately reflect internal ice dynamics or basal melting.