GRACE terrestrial water storage (TWS) using improved point-mass (IPM) solution

The data sets contain the GRACE monthly terrestrial water storage (TWS) grids based on the improved point-mass (IPM) solution at Hohai University (HHU). <br> The HHU-IPM-GRACE records for monthly TWS values are in mm for the reference period April 2002 to September 2020 in the form of NetCDF files. They are anomalies regarding the period from January 2004 to December 2009. The data sets are provided at a spatial partitioning of 0.25-by-0.25 arc-degrees. (The resolution is still GRACE’s native resolution which is 3 arc-degrees.) The variables within the file ‘HHU_IPM_GRACE_TWS_200204_202009_v01.nc’ are ‘lat’ (latitude), ‘lon’ (longitude), ‘tws’ (terrestrial water storage), and ‘time’. Latitudes and longitudes are respectively 720-by-1440 matrices in arc-degrees (decimal), and the values refer to the cells' center. The TWS is a 720-by-1440-by-189 at which the rows refer to the latitudes, the columns refer to longitudes, and the pages refer to the epochs (189 monthly solutions). Time is a 189-by-1 vector containing the number of days since January 1, 2002. <br> A MATLAB code ‘read_hhu_ipm_tws.m’ is available for extracting the results and plotting the first month.