资源环境科技发展态势分析平台

Satellite-based precipitation estimates with high spatial and temporal resolution and large areal coverage have provided hydrologists a potential alternative source for hydrological applications since the last few years, especially for ungauged regions. This study evaluates five satellite-based precipitation datasets, namely, Fengyun, TRMM 3B42, TRMM 3B42RT, CMORPHBLD and CMORPH RAW, against gauge observations for streamflow simulation with a distributed hydrological model (SWAT) over the Huifa river basin, Northeast China. Results show that, by comparing the statistical indices (MA, MSP, STDE, ME, BIAS and CC) and inter annual precipitation, it is demonstrated that Fengyun TRMM 3B42 and CMORPH_BLD show better agreement with gauge precipitation data than CMORPH RAW and TRMM 3B42RT. When the SWAT model for each dataset calibrated and validated individually, satisfactory model performances (defined as: NS > 0.5) are achieved at daily scale for Fengyun, TRMM 3B42 and gauge-driven model, and very good performances (defined as: NS > 0.75) are achieved at monthly scale for Fengyun and gauge-driven model, respectively. The CMORPHBLD forced daily simulations also yield higher values of NS and R-2 than CMORPH RAW and TRMM 3B42RT at daily and monthly step. From the uncertainty results, variations of P-factor values and frequency distribution curves of NS suggest that the simulation uncertainty increase when operating the Fengyun, 3B42RT, CMORPH_BLD and CMORPH RAW-driven model with best fitted parameters for rain gauge SWAT model. The results also indicate that the influence of parameter uncertainty on model simulation results may be greater than the effect of input data accuracy. It is noted that uncertainty analysis is necessary to evaluate the hydrological applications of satellite-based precipitation datasets.