Climate Sensitivity of the Glacier Mass Budget of High Mountain Asia Based on Satellite Gravimetry
Abstract
The ice mass balance of High Mountain Asia is dominated by changes in glaciers, and snowpack, and affects water resources in densely populated areas of India, Pakistan, Nepal, and neighboring countries. Previous studies based on satellite imagery have attributed an accelerating reduction of ice and snow masses to atmospheric warming. Glaciers of the region are also known to be very sensitive to variations in temperature and precipitation, and the region's annual mass balance shows a robust interannual variability. On large scales, the Gravity Recovery and Climate Experiment (GRACE) and its Follow-On (GRACE-FO) mission provide observations of mass variation on and near the Earth's surface. Given other mass signals within a vicinity of about ~300-km, one can estimate glacier mass changes of the region. Here, we investigate the influence of climate variability, given as ERA5 (The European Centre for Medium-Range Weather Forecasts's fifth major global Re-Analysis) temperature and precipitation variability as well as precipitation variability by APHRODITE (Asian Precipitation - Highly-Resolved Observational Data Integration Towards Evaluation of Water Resources), on ice mass changes of a region encompassing the Karakoram and Himalaya. We isolate ice mass changes from total water storage changes, as provided from satellite gravimetry, by removing the influence of non-glaciological processes, including in-situ groundwater changes in northern India, changes in soil and post-glacial rebound. We conduct this analysis for the period 2002-2019 and when GRACE observations are available. Then we investigate the potential influence of temperature and precipitation on GRACE-based ice mass changes through a wavelet spectrum coherence analyses, in particular focusing on interannual variabilities. Moreover, we conduct a comprehensive comparison of ice mass losses, precipitation, and temperature with changes in hydrological variables (soil, groundwater, surface water, and river discharge). The results of the study will provide insight into the mechanism of accelerated glacier melting in High Mountain Asia. With that, the results have the potential to improve our ability to predict how climate change will alter the timing and amount of surface water availability of High Mountain Asia.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.C43A..07S
- Keywords:
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- 0720 Glaciers;
- CRYOSPHERE;
- 0740 Snowmelt;
- CRYOSPHERE;
- 0758 Remote sensing;
- CRYOSPHERE;
- 0776 Glaciology;
- CRYOSPHERE