Reconstruction of continuous GRACE/GRACE-FO terrestrial water storage anomalies based on time series decomposition

• We propose a simple and robust method for reconstructing continuous GRACE-like TWSA. Reconstructed data using piecewise trends is better in capturing anomalous change. TWSA detects the Australian drought during gaps 2018. Since 2002, terrestrial water storage anomalies (TWSA) derived from Gravity Recovery Climate Experiment (GRACE) its successor, GRACE Follow-on (GRACE-FO), have been widely used resources management , monitoring forecasting. However, disrupted time series due to temporal gap (i.e., July 2017 May 2018) between two missions limits further applications. To bridge this gap, we reconstruct by combining GRACE/GRACE-FO (including long-term trend trends) with de-trended of Humphrey Gudmundsson's datasets period April 2002 2019 over Australia. These reconstructed are evaluated against GRACE/GRACE-FO, balance model, three recently published products. Results suggest that our based on shows great consistency comparing other products correlation coefficient (R) 0.98, root-mean-square error (RMSE) 0.70 cm, Nash-Sutcliffe efficiency (NSE) 0.96. The proposed reconstruction approach presented current study straightforward efficient enable seamless continuation GRACE-FO regional global hydrological studies.