Utility of integrated IMERG precipitation and GLEAM potential evapotranspiration products for drought monitoring over mainland China

In this paper, we comprehensively evaluated the utility of integrated long-term satellite-based precipitation and evapotranspiration products for drought monitoring over mainland China. The latest Integrated Multi-satelliteE Retrievals Global Precipitation Measurement V06 three Runs products, i.e., near real-time Early Run (IMERG-E) Late (IMERG-L) post-real time Final (IMERG-F), Land Evaporation Amsterdam Model V3.3a (GLEAM) potential (PET) from 2001 to 2017 were considered. accuracy IMERG GLEAM PET was first against observed Penman-Monteith method estimated PET, respectively, based on dense meteorological station network. Standard Evapotranspiration Index (SPEI) calculated (SPEIs, including SPEIE, SPEIL SPEIF corresponding IMERG-E, IMERG-L IMERG-F, respectively) then validated by using SPEI data (SPEIm) at multiple temporal-spatial scales. Finally, four typical events selected analyse ability SPEIs characterize evolution situations. results showed that IMERG-F presents much better performance than IMERG-E in terms higher CC smaller BIAS RMSE values well simulated change trend reference but generally underestimated Northwest China (NW), Xinjiang (XJ) Qinghai–Tibet plateau (TP). general, performances eastern Southwest (SW) significantly superior their NW, XJ, TP regions. Even though performed best, SPEIE also reasonably some specific can capture temporal process reflect spatial characteristics events. It is thus highlighted (especially IMERG-F) could be used as alternative sources comprehensive monitoring, account water balance principle China, particularly SW outcomes study will provide valuable references integration multi-source remote-sensing datasets GPM era.