Spatiotemporal deformation analysis of glaciers and surrounding landscapes in the Shishapangma region using InSAR techniques

Glacier dynamics in the Himalayan mid-latitudes, particularly in regions like the Shishapangma, are not yet fully understood, especially the localized topographic and climatic impacts on glacier deformation. This study analyzes the spatiotemporal characteristics of glacier surface deformation in the Shishapangma region using the Small Baseline Subset (SBAS) Interferometric Synthetic Aperture Radar (InSAR) technique. The analysis reveals an average deformation rate of -4.02±17.65 mm/yr across the entire study area, with glacier regions exhibiting significantly higher rates of uplift (16.87±13.20 mm/yr) and subsidence (20.11±14.55 mm/yr) compared to non-glacier areas. It identifies significant surface lowering on the mountain flanks and localized uplift in certain catchments, emphasizing the higher deformation rates in glacial areas compared to non-glacial ones. We found a strong positive correlation between temperature and cumulative deformation (correlation coefficient of 0.63), particularly in glacier areas (0.82). The research highlights the role of temperature as the primary driver of glacier wastage, particularly at lower elevations, with strong correlations found between temperature and cumulative deformation. It also indicates the complex interactions between topographic features, notably, slope gradient, which shows a positive correlation with subsidence rates, especially for slopes below 35°. South-, southwest-, and west-facing slopes exhibit significant uplift, while north-, northeast-, and east-facing slopes predominantly subside. Additionally, we identified transition zones between debris-covered glaciers and clean ice as areas of most intense deformation, with average rates exceeding 30 mm/yr, highlighting these as potential high-risk zones for geohazards. This study comprehensively analyzes the deformation characteristics in both glacier and non-glacier areas in the Shishapangma region, revealing the complex interplay of topographic, climatic, and hydrological factors influencing glacier dynamics.