Terrestrial Water Storage Anomalies

Terrestrial Water Storage (TWS) variability as observed by GRACE/GRACE-FO is an integrated signal from a number of different processes. The GravIS TWS Level-3 products represent anomalies relative to the long-term mean over the period 2002/04 through 2020/03, provided in terms of cm of equivalent water height.

Gridded TWS Level-3 products are displayed in the spatial plot. These products contain several individual variables which can be selected by clicking on the respective name of a particular variable next to the spatial plot, or by using the corresponding pulldown menu in the spatial plot. The gridded products, provided in NetCDF format, can be downloaded from the ISDC archive, either based on gravity field time series from GFZ or COST-G .

For each selected variable, globally averaged anomalies as well as averaged anomalies for certain regions are displayed in the time series plot. Use the corresponding pulldown menu in the spatial plot to select between two types of predefined regions: river basins or climatically similar regions (regions with similar precipitation properties). Click on the spatial plot to select a particular region. Note that TWS uncertainty estimates for regional averages (except global average) are not simply derived from the grid point uncertainties, but modelled according to Boergens et al. (2022). All available regional averaged TWS time series, provided as CSV files, can be directly downloaded from this site by clicking on the download button above the time series plot. The geometries of the predefined regions are available here for the river basins and here for the climatically similar regions .

Further information on the TWS data products and the applied processing scheme is available here as technical note.