Applicability analysis of multiple precipitation products in the Qaidam Basin, Northwestern China

In the Qaidam Basin, meteorological stations are sparsely distributed, and the observational precipitation data are therefore not comprehensive, which significantly hampers the accurate assessment and optimal allocation of regional water resources. This study aims to evaluate the accuracy of three precipitation products (MSWEP V2, GPM IMERG V6, and TRMM 3B43) against gauged-based precipitation data from nine meteorological stations and 12 hydrologic stations in the Qaidam Basin from 2001 to 2016. The results reveal the following: (1) At the annual and monthly scales, the MSWEP product has the highest accuracy, followed by the GPM product. However, the TRMM product only reveals a correlation at the monthly scale; (2) the MSWEP product performs better in the wet season than the dry season, and the TRMM product has an abnormally high value of precipitation in the wet season. Moreover, it was shown that the accuracy of the GPM product is superior to that of the TRMM product; however, it has a low detection capability in some mountainous areas; and (3) the average error of each precipitation product at the meteorological stations is smaller than that at the hydrological stations.

Automated summary

The study evaluates the accuracy of three precipitation products in the Qaidam Basin against observed data. MSWEP product shows the highest accuracy at annual and monthly scales, followed by GPM product. TRMM product only exhibits correlation at the monthly scale and has abnormal values in the wet season. Additionally, GPM product has superior accuracy to TRMM but lacks detection capability in mountainous areas. The average error of each precipitation product is smaller at meteorological stations compared to hydrological stations.