Evaluation of CMIP6 Models Performance for Winter Cold Wave Frequency in China

Based on the observational data from 1961 to 2013 and the minimum temperature data of 32 climate models in the Coupled Model Intercomparison Project Phase 6 (CMIP6), the individual model and multi-model ensemble average ability to simulate the frequency of winter cold waves in China was evaluated. The authors selected the best models in different regions of China to provide theoretical support for future cold wave frequency projection and climate model improvement over China. The results reveal that CMIP6 global climate models can well reproduce the spatial characteristics of the cold wave frequency that gradually decreases from north to south. EC-Earth3-Veg has the best ability to stimulate the cold wave frequency over China. Most models can simulate the downward trend of the cold wave frequency, but the ability to simulate the magnitude of trend changes is relatively limited. Compared with the single model, the multi-model equal weight average and multi-model median average improve the simulation effect of the spatial pattern of the winter cold wave frequency in northern China and southern China, respectively. However, the simulation of the trend is generally low.