Abstract
Using the maximum temperature, minimum temperature and average temperature data from the 0.5° × 0.5° grid datasets (V2.0) covering China during 1961–2022, this study conducts a temporal and spatial analysis of temperature trend variations in summer in the region of east of 110°E in China. The results indicate that all the three temperatures show an increasing trend from 1961 to 2022, with the minimum temperature exhibiting a faster warming rate. After 2011, the three temperatures rise significantly higher than that in previous decades, with the average and maximum temperatures increasing by 0.04°C and 0.05°C, respectively. Approximately 22.34% part of the study region is covered with an annual average temperature between 27–30°C, increasing 14.49% compared to the smallest proportion. And the area with the annual average maximum temperature ranging from 30–33°C reach 64.1%. After 2011, the frequency of grid points experiencing heatwaves are more than 60 times which is doubled compared with other decades,while with an earlier onset dates occurring on April 2nd and later retreat dates on October 12th. In the summer of 2022, all three temperatures in the region show hotter than the annual average, with high anomaly values concentrating on the central area. Additionally, based on the hindcast of four operational models in 2022, this study evaluates their abilities to predict high temperature and heatwaves in the summer of 2022. The result shows that UKMO exhibits the best capability for predicting maximum temperature and heatwave. The results suggest that the heat extremes can become more frequent and intenser in the coming decade. And the evaluation of four models can provide some help to improve the ability of prediction.