A High-Accuracy Rainfall Dataset by Merging Multi-Satellites and Dense Gauges over Southern Tibetan Plateau for 2014–2019 Warm Seasons

Abstract. Tibetan Plateau (TP) is well known as the Asia’s water tower from where many large rivers originate. However, due to complex spatial variability of climate and topography, there is still a lack of high-quality rainfall dataset for hydrological modelling and flood prediction. This study, therefore, aims to establish a high-accuracy daily rainfall product through merging rainfall estimates from three satellites, i.e., GPM-IMERG, GSMaP, and CMORPH, based on the likelihood measurements of a high-density rainfall gauge network. The new merged daily rainfall dataset with a spatial resolution of 0.1°, focuses on warm seasons (June 10th–October 31st) from 2014 to 2019. Statistical evaluation indicated that the new dataset outperforms the raw satellite estimates, especially in terms of rainfall accumulation and the detection of ground-based rainfall events. Hydrological evaluation in the Yarlung Zangbo River Basin demonstrated high performance of the merged rainfall dataset in providing accurate and robust forcings for streamflow simulations. The new rainfall dataset additionally shows superiority to several other products of similar types, including MSWEP and CHIRPS. This new rainfall dataset is publicly accessible at https://doi.org/10.11888/Hydro.tpdc.271303 (Li et al.,2021).