An integrated assessment of heat hazard, vulnerability, and accessibility to climate shelter networks for identifying urban adaptation priority areas in Andalusia (Spain)

Climate change is intensifying the effects of extreme heat, particularly in urban environments, posing a risk to public health and disproportionately affecting vulnerable populations. Urban climate shelters have emerged as a short-term adaptation measure, yet their deployment is often based on existing infrastructure and do not systematically respond to spatial patterns of heat hazard or social vulnerability. This study develops an integrated framework to assess the accessibility of climate shelter networks while explicitly accounting for territorial variations in hazard and population vulnerability. The approach combines hazards and vulnerability indices with network-based accessibility analysis to identify priority areas for intervention and urban adaptation planning. Applied to Andalusia (southern Spain), a Mediterranean climate change hotspot, the results reveal significant spatial mismatches between heat hazard and access to climate shelters, highlighting areas of compounded vulnerability. Results show that more than 50% of the resident population in Andalusia live in high or very high priority areas, considering hazard, vulnerability, and accessibility to climate shelters. The study provides a transferable, equity-oriented methodology to support disaster risk reduction and climate adaptation strategies under increasing heat stress. • An integrated, equity-oriented framework combines heat hazard, social vulnerability, and pedestrian accessibility to identify priority areas for climate shelter planning at fine spatial resolution. • Network-based walkability analysis reveals spatial mismatches between heat exposure and access to climate shelters. • The results highlight pronounced territorial inequalities, particularly in urban peripheries and disadvantaged neighborhoods. • More than half of Andalusia’s population lives in high or very high priority areas for heat-risk intervention. • The proposed prioritization directly supports risk-informed, population-focused decision-making for urban heat adaptation and disaster risk reduction.