Data Service for Terrestrial Water Storage & Groundwater | C3S
Terrestrial Water Storage (TWS) and Groundwater are defined as Essential Climate Variables (ECV) by the Global Climate Observing System (GCOS). The variables are considered essential for contributing to a comprehensive view of Earth’s climate, its variability, and trends. Based on this, the European Union’s Copernicus Climate Change Service (C3S) will provide observation-based datasets for both variables.
Following the decade-long engagement of GFZ in the matter of gravimetry-based water cycle monitoring, a consortium led by Section 4.4 – Hydrology will establish a new ECV Service “Terrestrial Water Storage and Groundwater” in the C3S Land Hydrology lot. The service will cover the ECV products “Terrestrial Water Storage Anomaly” (TWSA) and “Groundwater Storage Change” (GWSC). The products will be published on the C3S Climate Data Store (CDS) in the near future.
The TWSA data will represent deviations from the long-term average of water stored on or below the Earth’s surface in the form of soil moisture, groundwater, surface water, snow and ice. The data will be available from April 2002 to present and are derived from observations of the Gravity Recovery and Climate Experiment (GRACE) satellite mission and its follow-on mission, GRACE-FO. Possible applications of the product include assessments of change in drought and flood magnitude and frequency, investigation of regional to continental hydrological processes and water budgets, or the quantification of ice mass loss of large glaciers and ice sheets.
TWSA is also the basis for the GWSC product. This product will follow the residual approach established in the Global Gravity-based Groundwater Product (G3P, LINK) and will provide groundwater storage anomalies for the corresponding periods. G3P and C3S GWSC are currently the only available observation-based products to assess groundwater on the basis of observations and on a global scale.
Further partners in the ECV Service are:
GFZ Section 1.3 – Earth System Modelling
GFZ Section 1.2 - Global Geomonitoring and Gravity Field
Combination Service for Time-variable Gravity Fields (COST-G)
Department of Geodesy and Geoinformation at TU Wien
Department of Geography at Uni Zurich
Satellite Services and Research group at the Finnish Meteorological Institute