Assessing the potential and hydrological usefulness of the CHIRPS precipitation dataset over a complex topography in Pakistan

This study evaluates the spatial and temporal performance of the Climate Hazard Group InfraRed Precipitation Satellite (CHIRPS) against Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA) 3B42/3B43 v. 7 and Global Precipitation Measurement (GPM)-based Integrated Multi-Satellite Retrievals for GPM (IMERG V06), from 2000 to 2013. Several statistical metrics were used to assess the performance of CHIRPS over the Indus Basin, and its hydrological utility is also assessed using the Soil and Water Assessment Tool (SWAT). The Gilgit and Soan basins were selected for hydrological modelling. The results demonstrate the spatial and temporal dependency of CHIRPS, i.e. better performance was observed in the Lower Indus Basin (LIB) while poor performance was observed in the Upper Indus Basin (UIB). The hydrological assessment of CHIRPS revealed poor performance (overestimation of streamflow) across the Gilgit Basin during both calibration and validation periods. Satisfactory to good performance was obtained across the Soan Basin.