High-Resolution Mapping of Rock Glacier Dynamics in the Sikkim Himalayas, Using Remote Sensing Data
摘要
This study focuses on mapping and analyzing 223 rock glaciers (RGs) in Sikkim, Eastern Himalayas, using high-resolution images from Google Earth Pro. The RGs were identified and mapped, with data on area, perimeter, slope, elevation, and aspect compiled into a comprehensive inventory. These glaciers, labelled RGXXX, cover a total area of 28.20 km2, with a notable distribution in southwest, northeast, northwest, and southeast orientations. Active glaciers showed high velocities, with maximum speeds reaching 51.21 m/year, while relict glaciers exhibited generally slower but sometimes significant movement. The study also utilized the Copernicus Digital Elevation Model (DEM) and Sentinel-2 multispectral data to derive slope, elevation, and velocity information, revealing a correlation between slope and velocity dynamics. Additionally, several lake-terminated rock glaciers were identified, predominantly relict, indicating potential hazards such as glacial lake outburst floods (GLOFs). These findings provide crucial insights into the behavior, stability, and potential risks associated with RGs in the Sikkim Himalayas, offering valuable data for climate change adaptation, water resource management, and hazard mitigation in this mountainous region.