Abstract
The Gravity Recovery and Climate Experiment (GRACE) data have been extensively used to evaluate the total terrestrial water storage anomalies (TWSA) from hydrological models. However, which individual water storage components (i.e., soil moisture storage anomalies (SMSA) or groundwater water storage anomalies (GWSA)) cause the discrepancies in TWSA between GRACE and hydrological models have not been thoroughly investigated or quantified. In this study, we applied GRACE mass concentration block (mascon) solutions to evaluate the spatio-temporal TWSA trends (2003–2014) from seven prevailing hydrological models (i.e., Noah-3.6, Catchment Land Surface Model (CLSM-F2.5), Variable Infiltration Capacity macroscale model (VIC-4.1.2), Water—Global Assessment and Prognosis (WaterGAP-2.2d), PCRaster Global Water Balance (PCR-GLOBWB-2), Community Land Model (CLM-4.5), and Australian Water Resources Assessment Landscape model (AWRA-L v6)) in Australia and, more importantly, identified which individual water storage components lead to the differences in TWSA trends between GRACE and hydrological models. The results showed that all of the hydrological models employed in this study, except for CLM-4.5 model, underestimated the GRACE-derived TWSA trends. These underestimations can be divided into three categories: (1) ignoring GWSA, e.g., Noah-3.6 and VIC-4.1.2 models; (2) underrating both SMSA and GWSA, e.g., CLSM-F2.5, WaterGAP-2.2d, and PCR-GLOBWB-2 models; (3) deficiently modeling GWSA, e.g., AWRA-L v6 model. In comparison, CLM-4.5 model yielded the best agreement with GRACE but overstated the GRACE-derived TWSA trends due to the overestimation of GWSA. Our results underscore that GRACE mascon solutions can be used as a valuable and efficient validation dataset to evaluate the spatio-temporal performance of hydrological models. Confirming which individual water storage components result in the discrepancies in TWSA between GRACE and hydrological models can better assist in further hydrological model development.
Highlights
Accurate quantification of total terrestrial water storage anomalies (TWSA) is indispensable for the prediction of regional food supply, energy production, human and ecosystem health, and economic and societal development [1], in arid and semi-arid environments (e.g., Australia)
The results showed that compared to Gravity Recovery and Climate Experiment (GRACE), all models underestimated the large water storage trends and most models underestimated the seasonal water storage amplitudes in tropical and arid basins, while land surface models generally overestimated the amplitudes in northern basins
This study aimed to use GRACE mascon solutions to evaluate the spatio-temporal performance of TWSA from hydrological models and identify which individual water storage components (i.e., SMSA or groundwater water storage anomalies (GWSA)) result in the discrepancies in TWSA between GRACE and hydrological models
Summary
Accurate quantification of total terrestrial water storage anomalies (TWSA) is indispensable for the prediction of regional food supply, energy production, human and ecosystem health, and economic and societal development [1], in arid and semi-arid environments (e.g., Australia). Such differences cause a linear trend of TWSA (2002–2014) simulated by these two models in the Murray–Darling river basin to show opposite variation, i.e., 3.78 mm/year for WaterGAP model but −4.58 mm/year for CLM-4.0 model [5]. April 2002–June 2017 2004.0–2009.999 [43,44] GGM-05C
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call