Consistency of Global SWE and Precipitation Variations using Satellite, In-Situ and Reanalysis Products

Abstract:

Mountain snowpack or snow water equivalent (SWE) stores significant amounts of water and it has been declining dramatically in recent decades due to the temperature rise and anthropogenic forcing. Also, as climate warms more snowfall is expected to be replaced by rainfall. We conduct a systematic investigation to evaluate changes of SWE over snow accumulation season in multi-dimensional aspects. This includes analysis of SWE products from satellite, models, and reanalysis (AMSR-E/AMSR2, GlobSnow, ERA5/MERRA2) and popular satellite-gauge and reanalysis precipitation product (e.g., GPCP, GPCC, ERA5/MERRA2). We also utilize changes in snowfall accumulation from GRACE as an ancillary alternative for evaluation because of its advantages in reducing dependence on other hydro-meteorological variables. With the leverage of in-situ, satellite and reanalysis precipitation/SWE products, this work offers a framework of global SWE variation analysis in conjunction with changes in precipitation estimates, which is expected to provide valuable consensus for various applications including water resources management, aspects of climate change, and future refinement of SWE and precipitation products.