Terrestrial water storage data based on the generalized three-cornered hat fusion method

The dataset combines three GRACE Mascon products (CSR, JPL and GSFC) using the generalized three-cornered hat method (GTCH) to generate, referred to as TWS_GTCH. The dataset spans from 2003 to 2022, with a spatial resolution of 0.5 degrees and a temporal resolution of monthly. We deduct 2004-2009 means from the three GRACE terrestrial water storage (TWS) Mascon products to ensure that they have the same reference period. To enhance the reliability of the results and eliminate differences between datasets, we employ the GTCH method to calculate the root mean square error (rmse) of the GRACE TWS data to assess uncertainty. Finally, we utilize the least squares method to fuse the data based on their uncertainties.