Multidecadal statistical reconstruction of GRACE (Gravity Recovery And Climate Experiment) like terrestrial water storage anomalies (TWSA) incorporating geodetic tracking data

Description: We developed a multidecadal, monthly GRACE-like reconstruction, TWSTORE (Terrestrial Water Storage Reconstruction), for the global land, excluding Antarctica and Greenland, for the period 1984-2020 on a 0.5° grid. Please note that the actual resolution of the data sets does not fit the grid resolution. The actual resolution of TWSTORE follows the GRACE resolution, which is around 330 km at the equator, compared to a resolution of 55 km for a 0.5° grid (Humphrey et al. 2023). 

Method: Our approach is based on a combination of reconstructed TWSA and large-scale gravity information from geodetic satellite laser ranging (SLR) and Doppler Orbitography by Radiopositioning Integrated on Satellite (DORIS) tracking (Löcher et al. 2025). The reconstructed TWSA data is based on regression approaches and machine learning techniques, utilizing predictor variables such as rainfall and land or sea surface temperature. We also provide variances for TWSTORE. The variances are derived by propagating the uncertainties of SLR/DORIS and the climate data reconstruction through our combination approach. 

For more information on the employed datasets and techniques both for generating the data-driven reconstruction and for the data combination, we refer to our manuscript titled "Multidecadal Reconstruction of total water storage changes by Combining pre-GRACE satellite observations and climate data."

Data format: The data is given in a netCDF4 format. The file contains the reconstruction TWSTORE, the estimated variances of TWSTORE, information on the grid, and the time vector. The time is given in seconds since January, 1 1984.

References:

Humphrey, V., Rodell, M., and Eicker, A.: Using Satellite-Based Terrestrial Water Storage Data: A Review, Surveys in Geophysics,
https://doi.org/10.1007/s10712-022-09754-9, 2023

Löcher, A., Kusche, J., and Nie, Y.: A 40-year record of the Earth’s time-variable gravity field from SLR and DORIS, Advances in Space
Research, pp. 1281–1291, https://doi.org/10.1016/j.asr.2025.05.089, 2025.