Rising global population coexposure to heatwaves and landscape fire-sourced air pollution.

Over half of the global population and populated areas experienced increasing coexposure to heatwaves and landscape fire-sourced air pollution from 2000 to 2019.

• Why it matters: This coexposure poses significant public health risks, especially in low-HDI countries, highlighting the need for targeted mitigation and adaptation strategies.
• What they did: The study analyzed spatial, temporal, and sociodemographic data from 2000 to 2019, revealing that 52.4% of populated areas and 55.9% of the population faced rising coexposure, with an average of 1.3 days per person annually.
• The result: Coexposure person-days increased by 5.5 billion per decade, driven mainly by rising coexposure intensity and population growth, especially in low-HDI countries, informing health impact assessments.