Evaluation of the precipitation of the East Asia regional reanalysis system mainly over mainland China

In this article, precipitation in a new regional reanalysis dataset, namely, the East Asia regional reanalysis system (EARS-CMA) with a 12-km resolution based on the Weather Research and Forecast (WRF) model, ERA-Interim, ERA5, TRMM 3B42V7, Climate Prediction Center Morphing Technique (CMORPH) and CN05.1, is compared in 2008-2017. The results show that EARS-CMA can capture the spatial features and temporal variation in precipitation over East Asia well. Focusing on mainland China, CMORPH performs worse in regard to winter precipitation and dryer areas than TRMM against CN05.1. Although ERA5 behaves better with integrated properties compared with ERA-Interim and EARS-CMA over East Asia, EARS-CMA produces more reliable annual, summer and winter mean precipitation pattern than ERA5 over the subregions dominated by large scales in mainland China, including the Tibetan Plateau and northwestern China, similar to its driving fields, ERA-Interim. In addition, the improvement from ERA-Interim to EARS-CMA can be obtained in reasonably reproducing precipitation seasonality in South China, Indo-China and southern Japan. Thus, the compatibility of EARS is outstanding in maintaining the advantages of its corresponding driving fields, ERA-Interim, as well as developing finer small scales. Although slightly behind ERA5 in the subregions affected by tropical systems and monsoons, EARS-CMA is competitive in acting as reference data for daily, seasonal, annual and interannual precipitation estimations over mainland China.