Evaluation and Projections of Summer Daily Precipitation over Northeastern China in an Optimal CMIP6 Multi-model Ensemble

Abstract

Abstract In the early summer of 2022, the average precipitation in Northeastern China (NEC) was 144.9 mm, which was 62% higher than the normal precipitation (89.5 mm), and was the largest amount of precipitation since historical records began in 1951. Based on the CN05.1 precipitation data, the summer precipitation simulated by the sixth Coupled Model Intercomparison Project (CMIP6) model was evaluated in the NEC region. The model performs well in reproducing the climatological spatial distribution and interannual variability of precipitation. The simulation effect of a multi-model ensemble is better than that of a single model. The top three optimal models (EC-Earth3-Veg, EC-Earth3 and MPI-ESM1-2-LR) can constitute the optimal model ensemble (HMME). Compared with a single model and an ensemble of all 20 models, HMME significantly reduces the wet bias on the southeastern side of the Da Xing-AN Ling Mountains. HMME projects that daily precipitation will show an increasing trend in NEC region from 2015 to 2100. Under the two scenarios of SSP245 and SSP585, the increase rates of precipitation are 0.05mm/10a and 0.15mm/10a respectively. Although precipitation trends varied between scenarios at different times of the year, by the end of the 21st century, precipitation increased significantly across the region, with the largest increase in precipitation located in the southern part of northeastern China.