Assessment of the WATCLASS hydrological model result of the Mackenzie River basin using the GRACE satellite total water storage measurement

Earlier efforts have been geared towards modelling the hydrological water balance of the Mackenzie River basin and its sub-basins using a coupled land surface-hydrological model for the Canadian cold region known as WATCLASS. The goal of this current study is to effectively inter-compare the resulting total water storage anomalies estimated from the gravity recovery and climate experiment (GRACE) satellite analysis with those estimated from the atmospheric-based water balance approach as well as the model output froth WATCLASS over the 1.8 x 10(6) km(2) Mackenzie River basin in Canada. Since the success of the parameter estimation stage of the coupled land surface-hydrological model. WATCLASS over this large catchment, was entirely based on a goodness of fit between the simulated and observed flows, it is often desirable to assess the reliability of the generated state variables prior to concluding on the overall efficiency of this model in reproducing the relevant hydrological processes over this region. A major challenge here lies in finding suitable dataset with which this comparison can be made to further assess the ability of the model in accurately reproducing other mass fluxes. The outcome of this inter-comparison reveals the potential application of the GRACE-based approach as a veritable tool required for the closure of the hydrological water balance of the Mackenzie River basin as well as serving as a dependable source of data for the calibration of traditional hydrological models. Copyright (C) 2009 John Wiley & Sons, Ltd.