Heatwave exposure inequality: An urban-rural comparison of environmental justice

The rapid growth of heatwaves' severity have increasingly endangered citizens' health in the last decade. Evidence points to the environmental injustice of heatwaves: inequal heatwave exposure among socioeconomic groups. Failing to use an adequate indicator of thermal comfort at a large scale, the previous studies have not adequately scrutinized the environmental justice of heatwaves and their variations across a large-scale territory. This study is novel in an unprecedented analysis of psychological equivalent temperature (PET), a comprehensive measure of thermal comfort, across socioeconomic groups and the urban-rural gradient of the Netherlands, as a proxy for factors affecting heatwave vulnerability. The results show that heatwave inequality (measured by the Gini coefficient) is higher in less urbanized areas. It shows that the population aged 25-44, immigrants, tenants, and females are the most heat-exposed groups across all levels of urbanization. However, the population aged 25-44 is more likely to be overexposed in urbanized areas, and immigrants are more likely to be overexposed in rural areas. The results open discussion on the necessity of location-specific policies protecting the most heatexposed groups in different areas. It also paves the way for future studies using broader PET simulations and expanding their scope to include citizens' daily movements.