Suitability of high-temporal satellite-based precipitation products in flood simulation over a humid region of China

Satellite-based precipitation products provide critical precipitation sources with high resolution for hydrologic forecasting. This study aims to assess the suitability of the near-real-time Early run and Late run of the Integrated Multi-satellite Retrievals for the Global Precipitation Measurement (IMERG) products (IMERG-E and IMERG-L), and the post-real-time Final run IMERG product (IMERG-F) and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis (TMPA) 3B42RT in flood simulation, particularly flood events, at hourly scale over a humid region of China. A statistical assessment of the accuracy of selected satellite-based precipitation products shows IMERG-F outperforms the others, and the performance of TMPA 3B42RT is generally better than that of IMERG-E and IMERG-L. Furthermore, IMERG-F performs the best in hourly streamflow simulation, as well as in flood event simulation, with a mean Nash-Sutcliffe efficiency coefficient of 0.71, while IMERG-E, IMERG-L and TMPA 3B42RT present overall acceptable performance. The simulated peak flows tend to be smaller than the observations, and the simulated time lags of occurrence are changeable. This study finds that IMERG and Tropical Rainfall Measurement Mission (TRMM) are suitable for hydrological simulations at hourly scale, and IMERG-E is an appropriate replacement for TMPA 3B42RT in this case.

Automated summary

Satellite-based precipitation products, particularly the IMERG-F product, show the best performance in flood simulation and hourly streamflow simulation in a humid region of China. The TMPA 3B42RT product generally performs better than IMERG-E and IMERG-L, with overall acceptable performance in hydrological simulations at hourly scale. The simulated peak flows are usually smaller than observed, and the simulated time lags of occurrence are variable.