Abstract
Extreme heat and particulate matter (PM2.5) pollution are among the deadliest environmental hazards that threaten humans and ecosystems. Their co-occurrence, known as compound heat-pollution events, can amplify risks far beyond those posed by either hazard alone, but their global patterns and physical mechanisms are yet to be understood. Here, we present a global assessment of compound heat-pollution events from 2003 to 2020 at 1-km fine scale. We identify two hotspots: Sub-Saharan Africa and the Indus River Valley, where compound heat-pollution events occur most frequently. These compound events are typically associated with clear and dry conditions characterized by increased solar radiation and reduced precipitation, humidity, and cloud cover. Notably, during compound events, there is a pronounced high-pressure anticyclone appearing in the Indus River Valley, while weaker atmospheric circulation changes appear in Sub-Saharan Africa. Our findings advance understanding of compound heat-pollution events and support improved risk assessments and regional adaptation strategies.
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Data availability
The daily temperature dataset at 1 km can be downloaded from https://doi.org/10.25380/iastate.c.6005185. The daily PM2.5 concentration dataset at 1 km can be downloaded from https://zenodo.org/communities/ecnu_lghap. The ERA5 reanalysis dataset at single level can be downloaded from https://cds.climate.copernicus.eu/datasets/reanalysis-era5-single-levels?tab=overview, and the pressure levels are publicly available via https://cds.climate.copernicus.eu/datasets/reanalysis-era5-pressure-levels?tab=overview.
Code availability
The codes used to identify extreme events and produce the main figures can be accessed at a Zenodo repository (https://doi.org/10.5281/zenodo.18875506).
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Acknowledgements
This study is funded by the National Natural Science Foundation of China (No. 42371028 and 42501023).
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Z.H. contributed to the investigation, visualization, and original draft of the manuscript. M.L. contributed to the conceptualization, methodology, and supervision of the project. W.S. contributed to the investigation and supervision of the manuscript. H.Z. and W.C. contributed to the draft and discussed the results. All authors contributed to the results discussion and the review and editing of the manuscript.
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Communications Earth and Environment thanks Chenghao Wang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Primary Handling Editor: ChenRui Diao. A peer review file is available.
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Huang, Z., Luo, M., Wu, S. et al. Global hotspots of compound extreme heat-pollution linked to local surface and atmospheric conditions. Commun Earth Environ (2026). https://doi.org/10.1038/s43247-026-03460-9
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DOI: https://doi.org/10.1038/s43247-026-03460-9
