Diagnosing local injustice in climate adaptation: spatial equity in the governance of cooling centers in Seoul

As heatwaves intensify under climate change, cities face growing pressure to ensure that climate adaptation resources are distributed equitably across communities. This study investigates spatial disparities in Seoul's cooling centres, analysing how existing administrative boundaries and governance units can exacerbate spatial inequality in heatwave response. We construct a composite Heat Risk Index (HRI) that integrates thermal hazards and socio-spatial vulnerability indicators. Then, we identify its alignment with the distribution of cooling centres at both the Planning (district) and Implementation (neighbourhood) levels. While Gini coefficient analysis suggests relatively low disparity at the planning scale, significant inequality emerges at the implementation level – revealing a mismatch between policy design and on-the-ground service delivery. A Z-score-based sensitivity analysis identified 49 mismatched neighbourhoods (32 relative beneficiaries and 17 deprivations). Deprivation areas are concentrated in older, inner-city zones with high elderly populations and the poor, whereas relative beneficiaries are typically low-density or peripheral areas with lower heat risk. Using interpretable machine learning methods (XG Boost and SHAP), we find that administrative convenience, rather than social vulnerability, predominantly explains the current allocation of cooling centres – suggesting governance practices that may reinforce or sustain spatial imbalance. By linking distributive outcomes with their institutional rationales, this study connects empirical assessment with the normative dimension of spatial justice, conceptualising equity to realise justice. By doing so, it establishes a framework that can be used to integrate equitable and adaptive urban climate policies in other cities.