New spectro-spatial downscaling approach for terrestrial and groundwater storage variations estimated by GRACE models

The study proposes a new mathematical method, referred to as spectral combination, downscale Gravity Recovery And Climate Experiment (GRACE) observations. goal is improve the spatial resolution of GRACE from 1? 0.25?, based upon available hydrological variables. First, approach condition adjustment proposed estimate uncertainties related Second, spectral-spatial estimator developed derive downscaled Total Water Storage Anomalies (TWSA) by optimally combining models and Last, groundwater storage anomalies (GWSA) are derived TWSA. combination was tested over Canadian Prairies considering data required Global Land Data Assimilation System (GLDAS) variables for February 2003 December 2016. results reveal greater details in TWSA after downscaling. Quantitatively, retrieved GWSA were validated using 75 unconfined situ piezometric wells that distributed across Province Alberta. A correlation 0.80, with an RMSE 11 mm, obtained downscaling all validation area. These better than those before (correlation 0.42, 21.4 mm), demonstrating successful.