Sociodemographic Disparities in Global Compound Event Exposure for Cold Spells and PM2.5 Pollutions
Yujia Huang1,2,3,4, Yahan Gu1, Pei Yu2
1State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China.
Environmental Science & Technology
|May 20, 2026
Summary
Compound events, where cold spells and fine particulate matter (PM2.5) pollution coincide, are increasing globally. These events disproportionately affect Asia and Africa, highlighting significant health and economic disparities.
Area of Science:
- Environmental Science
- Public Health
- Climate Science
Background:
- Cold spells and fine particulate matter (PM2.5) pollution often occur simultaneously, exacerbating health and economic consequences.
- The spatiotemporal patterns and inequalities associated with these compound events are not well understood.
Purpose of the Study:
- To define and assess the spatiotemporal characteristics and disparities of compound cold spell and PM2.5 pollution events.
- To analyze global trends and regional inequities in exposure to these combined environmental hazards.
Main Methods:
- Defined compound events as days with both cold spell and PM2.5 pollution.
- Assessed spatiotemporal trends and disparities at a grid scale from 2000 to 2023.
- Quantified population exposure and analyzed demographic and geographic variations.
Main Results:
- Global compound event exposure has increased, with significant regional disparities.
- Europe experienced widespread exposure (86% of the population), while Asia and Africa showed the most significant increases in event days and exposure.
- Total exposure rose from 64.5 to 91.3 million person-days, with high-income countries showing the highest levels and affecting young adults, males, and urban populations most.
Conclusions:
- The study reveals increasing global exposure to compound cold spell and PM2.5 pollution events.
- Significant economic and regional disparities exist in exposure, with Asia and Africa facing growing burdens.
- Findings underscore the need to address inequities in compound exposure, particularly in vulnerable regions and populations.
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