Based on ERA5 reanalysis data and downscaled CMIP6 model simulation data, the authors analyze the wet-bulb temperature changes and moist-heat conditions in the eastern China’s monsoon region from 1981 to 2020. It also predicts the changes under the SSP2-4.5 and SSP5-8.5 emission scenarios from 2046 to 2055 and evaluates the high moist-heat exposure risk for people. The results indicate that from 1981 to 2020, the wet-bulb temperature in the eastern China’s monsoon region generally increased. During the daytime, the annual maximum wet-bulb temperature significantly rose in the western and eastern coastal region, while it decreased in some southern regions. At night, the change was mainly characterized by an increase. The annual average wet-bulb temperature increased both during the day and at night. Moist-heat weather during the daytime mainly occurred in the southern region, followed by the northern region, with the least occurrence in the central region. The spatial pattern of high moist-heat weather showed a distribution of more in the north and less in the south. At night, moist-heat weather mainly occurred in the northern and eastern parts, with high moist-heat weather being extremely rare. Under the SSP2-4.5 and SSP5-8.5 scenarios, the frequency and distribution of various types of moist-heat weather in the future will change in a complex manner. The central, eastern, southern China and the southwestern parts of the study region are projected to experience a decrease in moist-heat weather but an increase in high moist-heat weather. In other regions, both types of moist-heat weather are expected to increase. There will be an increase of 0–50 days per year in the northern region, while most of the southern regions will experience an increase of 50–100 days per year. In the future, the population exposure risk to high moist-heat conditions is expected to be relatively low in the northern region. However, the southern region will face moderate to high exposure risks, where urgent measures need to be taken to address these challenges. 

基于ERA5再分析数据和CMIP6模式的降尺度数据, 分析中国东部季风区1981—2020年湿球温度的变化和湿热天气情况, 并预估 SSP2-4.5和SSP5-8.5排放情景下2046—2055年湿热天气的变化情况, 结合人口数据评价人群高湿热暴露风险。结果表明, 1981—2020年, 中国东部季风区湿球温度总体上呈现升高的趋势。白天, 研究区西部和东部沿海地区湿球温度年最大值显著上升, 南方局部区域下降; 夜晚, 研究区内湿球温度年最大值以上升为主; 昼夜湿球温度年平均值整体上为上升趋势。白天, 湿热天气主要出现在研究区南部, 北部次之, 中部最少, 高湿热天气则呈现北多南少的空间格局; 夜晚, 湿热天气主要出现在研究区北部和东部, 高湿热天气极少出现。在SSP2-4.5和SSP5-8.5情景下, 未来各类湿热天气的发生频率和分布范围变化情况复杂, 华中、华东、华南和研究区西南部将出现湿热天气减少、高湿热天气增加的变化趋势; 其他区域的湿热天气和高湿热天气均会增加, 北方每年将增加0~50天, 南方大部每年将增加50~100天。未来, 研究区北部高湿热暴露风险较低, 南部面临中度甚至高度的高湿热暴露风险, 亟须采取应对措施。