Evaluation of Satellite-Based Precipitation Products over Complex Topography in Mountainous Southwestern China

Satellite-based precipitation products (SBPPs) are essential for rainfall quantification in areas where ground-based observation is scarce. However, the accuracy of SBPPs greatly influenced by complex topography. This study evaluates performance Integrated Multi-satellite Retrievals GPM (IMERG) and Global Satellite Mapping Precipitation (GSMaP) characterizing a mountainous catchment southwestern China, with an emphasis on effect three topographic variables (elevation, slope, aspect). The evaluated comparing rain gauge observations at eight ground stations from May to October 2014–2018. Results show that IMERG GSMaP have good detection capability entire region, POD = 0.75 0.93, respectively. In addition, overestimates (BIAS −48.8%), while consistent −0.4%). Comprehensive analysis shows more impacted elevation, then whereas aspect has little impact. independent evaluations suggest variability elevation slope negatively correlate SBPPs. presents weaker dependence topography than area. Our findings demonstrate applicability catchments Southwest China. We confirm impacts SBPPs, especially areas. It suggested taking topographical factors into account needed hydrometeorological applications such as flood forecasting, SBPP retrieval technology require further improvement future better applications.