Mass Variations in the Siberian Permafrost Region Based on New GRACE Results and Auxiliary Modeling

GRACE (Gravity Recovery And Climate Experiment) determines the integral mass variations in the Earth system with a high spatial-temporal resolution. These mass variations should be adequately separated for better understanding of the individual signal contributions. In Siberia, the temporal mass variations are related to hydrological processes including thawing of permafrost layers. Permafrost layers with different thickness cover about 80% of Siberia. These frozen sheets play an important role for sea level rise and the global hydrological water cycle. In this study, the integral mass variations in Siberia are precisely estimated based on the new release of GRACE (RL05a) from GeoForschungsZentrum (GFZ) in Potsdam. In addition, various hydrological contributions (lake level variation, river run-off, etc.) can be estimated from different models and specific data. Here, mass variations in the Siberian permafrost region based on GRACE results and different hydrological models/data [i.e., GLDAS (Global Land Data Assimilation System) and GPCP (Global Precipitation Climatology Project)] are jointly investigated.