The increasing frequency of heatwaves over East Asia (EA) is impacting agriculture, water management, and people’s livelihood. However, the effect of humidity on high-temperature events has not yet been fully explored. Using observations and future climate change projections conducted with the latest generation of Earth System models, we examine the mechanisms of dry and moist heatwaves over EA. In the dry heatwave region, anticyclonic circulation has been amplified after the onset of heatwaves under the influence of the convergence of anomalous wave activity flux over northern EA, resulting in surface warming via adiabatic processes. In contrast, the moist heatwaves are triggered by the locally generated anticyclonic anomalies, with the surface warming amplified by cloud and water vapor feedback. Model simulations from phase six of the Coupled Model Intercomparison Project projected display intensification of dry heatwaves and increased moist heatwave days in response to projected increases in greenhouse gas concentrations.

东亚 (EA) 的热浪频率不断增加，正在影响农业、水资源管理和人民生计。然而，湿度对高温事件的影响尚未得到充分探索。利用最新一代地球系统模型进行的观测和未来气候变化预测，我们研究了东亚地区干湿热浪的机制。在干热浪区，受异常波活动通量汇聚的影响，热浪发生后反气旋环流在东部东亚地区上空被放大，导致地表绝热升温。相比之下，潮湿的热浪是由局部产生的反气旋异常触发的，而地表变暖则被云和水汽反馈放大。