A global assessment of intensified heatwaves and air quality

<h2>Summary</h2> Global surface temperatures have risen rapidly over the past decades, with the Earth experiencing its hottest summer on record in 2024. Concurrent with this temperature rise, the frequency and duration of heatwaves have also increased significantly. The impacts of heatwaves are substantial, affecting human health, economy, energy demands, and crop yields. Moreover, heatwaves play a crucial role in deteriorating air quality by influencing the formation of ozone (O₃) and fine particulate matter (PM_2.5). Although some studies have examined these effects, they often concentrate on short-term heatwaves in particular regions, neglecting a comprehensive global analysis. Additionally, heatwaves can lead to compound extreme events such as droughts and wildfires, posing new challenges for studying the effects of high temperatures on air quality. This review addresses these limitations and provides suggestions for future research to elucidate the complex mechanisms linking heatwaves to air pollution.