Global aging exacerbates heat exposure risk across diverse socioeconomic pathways

Abstract

Elderly individuals disproportionately face heat exposure risk compared to other demographic groups, with projected amplification in the future. The vast disparities between Global North and South countries necessitate a comprehensive understanding of the underlying factors influencing future heat exposure vulnerabilities. Here, we use factor decomposition method to quantify the contribution of climate change, population, and aging to heat exposure risk under four shared socioeconomic pathways (SSP) (SSP126, SSP245, SSP370, SSP585) from 2000 to 2100 at 20-year intervals. Results demonstrate a projected global escalation in heat exposure risk by 16 and 76 times under SSP126 and SSP585, respectively, with the North generally suffering lower risk than the South. Climate change emerges as a pivotal driver of future heat exposure risk in the North while aging notably influences the South. Despite climate change is projected to reduce heat exposure risk by up to 10 % in the North under SSP1-2.6 by the end of the 21st century, aging remains a critical risk factor.

Keywords

Heat exposure risk / Global south / Global north / Elderly people

CRediT authorship contribution statement

Xiao Chen: Writing – review & editing, Writing – original draft, Validation, Software, Methodology, Formal analysis, Data curation, Conceptualization. Song Leng: Writing – review & editing, Visualization, Validation. Zhaowu Yu: Writing – review & editing, Visualization, Methodology, Formal analysis. Ranhao Sun: Writing – review & editing, Visualization, Validation, Supervision, Methodology, Funding acquisition, Conceptualization.

Declaration of competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgements

This work was supported by the National Key R&D Program of China (Grant No. 2022YFF1303101) and the open fund project of the State Key Laboratory of Regional and Urban Ecology (Grant No. SKLURE2023-2-4).

Supplementary materials

Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.geosus.2025.100318.

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