Mapping Climate–Health Vulnerabilities in Indonesian Coastal Cities Using Socio-Economic and Satellite Data

Coastal societies face increasing health risks from climate change, such as weather-related extreme conditions, environmental destruction, and the occurrence of epidemics, posing significant challenges to sustainable development. There is a need to accurately measure the risks in place through integrating the climate variability with socio-economic exposure and health components to support long-term resilience and sustainable adaptation. This study conceptualized and validated a composite index-based method to assess climate–health risks across three Indonesian coastal cities: Banda Aceh, Mataram, and Ambon. This validation process was conducted by checking for face validity and consistency between sub-indices, as well as conformity to existing frameworks in the literature. Using satellite-derived climate data, national socio-economic statistics, and public health records, we identified the key parameters (hazard, sensitivity, exposure, and adaptive capacity) and quantified the risk levels for 190 villages. The results show that over 92% of villages fall into the high or very high risk categories, with universal high sensitivity and low adaptive capacity (78.95%). This points towards structural inequalities that hinder sustainable development. Spatial and quadrant analyses revealed region-specific vulnerabilities where Ambon showed higher hazard exposure (56% high and 42% very high). The findings provide policymakers and stakeholders with priority areas for targeted interventions and actionable suggestions to support public health planning, equitable resource allocation, and long-term sustainable coastal development.