Heatwaves are projected to substantially increase at a global scale, exacerbating worldwide heat-related risks in the future. However, understanding future heterogeneous heatwave changes and their origins remains challenging. By analyzing the output of various climate models from the Coupled Model Intercomparison Project Phase 6, we found pronounced spatial disparity of projected heatwave increases in the Northern Hemisphere, even outstretching seven-fold inter-regional differences in extreme heatwave occurrences, attributed primarily to future changes in heat-dome-like circulations and soil moisture–temperature coupling. Specifically, we found that by the end of the 21st century, the modulations of combined Pacific El Niño and positive Pacific Meridional Mode on magnified heat-dome-like circulations would be translated into summertime hotspots over western Asia and western North America. Amplified soil moisture–temperature couplings then further aggravate the heatwave intensity over these two hotspots. This study provides support for formulating impact-based mitigation strategies and efficiently addressing the potential future risks of heatwaves.

预计热浪将在全球范围内大幅增加，从而加剧未来全球范围内与热有关的风险。然而，了解未来的异质热浪变化及其起源仍然具有挑战性。通过分析耦合模型比较项目第六阶段的各种气候模型的输出，我们发现北半球预计热浪增加的明显空间差异，极端热浪发生的区域间差异甚至扩大了七倍，这主要归因于未来的变化在热穹状循环和土壤湿度-温度耦合中。具体来说，我们发现，到21世纪末，太平洋厄尔尼诺现象和太平洋正经向模态的组合对放大的热穹状环流的调节将转化为西亚和北美西部的夏季热点。土壤湿度-温度耦合的放大进一步加剧了这两个热点地区的热浪强度。这项研究为制定基于影响的缓解策略和有效应对热浪未来的潜在风险提供了支持。