Enhancing understanding of vulnerability and resilience to flash floods through comparative analysis of multidimensional indices

This study examines the relationship between vulnerability and resilience concerning flash flood risk in Castilla y León, Spain. It compares vulnerability and resilience indices and examines their relationships with variables related to flash flood risk. It also discusses improving assessments through a multidimensional approach, which includes social, economic, ecosystemic, physical, institutional, and cultural dimensions. Our approach uses statistical and spatial techniques, including Spearman correlations, bivariate choropleth maps, and regression models. Results show that vulnerability and resilience are related but distinct concepts. The correlation between their indices is weak (r = 0.06), but there are significant correlations between specific elements. For instance, the resilience index and the exposure component of the vulnerability correlate significantly (r = 0.40). Spatial regressions show a local R² value of 0.74 between the resilience index and vulnerability dimensions. Some elements of vulnerability are also significantly correlated to certain variables related to flash flood risk. These are mostly the exposure component (r = 0.59 for the population at risk) and the institutional dimension (r = −0.48 for the total flood indemnities provided by the insurance company). With a local R² of 0.85, the vulnerability and resilience indices show significant spatial regression with the critical infrastructure at risk. These results highlight the need for improved assessments of resilience and vulnerability especially adapted for local contexts. This emphasizes the need of a multidimensional approach combining theoretical frameworks with practical applications to guide future research initiatives and inform policymakers.