Abstract ID: 3.9878 | Accepted as Talk | Talk/Oral | TBA | TBA

This study evaluates the changes in snow/ice cover, snowline mapping, surface ice velocity, and glacier lake surface area in the Indus Basin, located in the Northwestern Himalayas. Using Landsat imagery spanning from 1997 to 2023, we delineated these changes. Multispectral and multi-temporal optical satellite data have been extensively used for glacier mapping and monitoring, particularly in assessing their retreat. Satellite remote sensing, combined with advanced image processing techniques, enables the precise retrieval of critical glacier parameters. This research uses remote sensing satellite data and GIS software to focus on surface-change delineation. We employed multi-temporal satellite data from Landsat MSS, TM, ETM+ sensors, OLI/TIRS, and ASTER DEM as primary datasets for snow and ice pixel extraction. The Normalized Difference Snow Index (NDSI) was utilized to extract pure snow and ice pixels, fresh snow, debris-covered snow/ice areas, and pixels mixed with shadows to demarcate surface area changes. Manual delineation was undertaken to enhance accuracy. The ASTER digital elevation model (DEM) provided data to determine the altitude of the snow line altitude (SLA). Variations in glacier parameters are directly related to climate change. Changes in glacial extent, equilibrium line altitude (ELA), and mass balance are crucial indicators of glacier health and their response to climate change. Our results indicate that the snow/ice surface area in the Upper Indus Basin decreased from 2007.90 km² in 1997 to 1982.95 km² in 2023, a decrease of 24.95 km2 or -1.24%. The Lower Indus basin, with 202 glaciers, remained nearly stable, with a slight reduction from 4154.95 km2 to 4154.65 km2, a decrease of 0.3 km2 or -0.0072%. The Accumulation Area Ratio (AAR) indicated a gradual decline in the accumulation zone in recent years. Additionally, glacial lakes were mapped using manual digitization, revealing that their total area increased from 5.05 km² in 1997 to 6.70 km² in 2023. This study highlights the significant changes in glacier parameters in the Indus Basin over the past few decades, underscoring the impact of climate change on these critical water resources.