Analytical hierarchy process-based mapping of social vulnerability to climate change in mountainous communes across Northwestern Vietnam

Mountainous regions are highly climate-vulnerable. Despite this, fine-scale assessments of social vulnerability to climate change in mountainous regions remain limited. This study addresses this gap for mountain communities in Vietnam by mapping social vulnerability at the commune level (the smallest administrative unit) by combining the analytical hierarchy process (AHP) with nationwide socioeconomic data. Van Yen District in Yen Bai Province was selected as the research area of focus because it reflects the broader conditions of northwestern mountainous regions in Vietnam, including a high dependence on rain-fed agriculture, high ethnic diversity, infrastructural constraints, and recurrent exposure to multiple hazard-induced disasters. The framework defines social vulnerability as a function of sensitivity and adaptive capacity. Our results reveal that communes in the central and southern parts of Van Yen exhibit moderate to very high social vulnerability to climate change, primarily driven by high sensitivity and low adaptive capacity. Of the 18 indicators analyzed, six were found to have statistically significant effects on vulnerability, namely population density, proportion of women, aquaculture area, proportion of ethnic minorities, housing quality, and access to clean energy. These findings provide actionable insights for local governments to better target vulnerable communities and prioritize resources for climate adaptation and disaster risk reduction. Our analytical approach demonstrates the transferability of AHP-based fine-scale mapping to mountainous regions, offering a practical tool for advancing equitable and sustainable adaptation planning nationally and globally.