Extreme heat vulnerability in Phoenix, Arizona: A comparison of all-hazard and hazard-specific indices with household experiences

摘要

Practitioners and researchers use vulnerability indices to understand the conditions that influence hazard risk. However, there has been little research on how well such indices depict household-scale vulnerability to specific hazards. We examined relationships between an all-hazard index and a hazard-specific index with householdlevel adaptive resources, adaptive behaviors, proximate sensitivities, and self-reported health outcomes related to extreme heat. Household measures were drawn from a stratified random sample survey conducted in Phoenix, Arizona, USA (n = 163). The results point to different experiences between households in more and less heat vulnerable areas. The largest differences between households stratified by the hazard-specific index (Heat Vulnerability Index) primarily involved adaptive resources and behaviors, whereas indicators of proximate sensitivity were more strongly differentiated by the all-hazard index (Social Vulnerability Index). Differences in health outcomes between more and less vulnerable neighborhoods were more evident using HVI than SoVI, although effect sizes using either index were small and confidence intervals were wide. The relationship between vulnerability indices and several survey measures varied across four study sites. The specific ways in which more and less vulnerable communities differ from one another varies based on the adaptation, sensitivity, or outcome measure of interest, location within the city, and choice of vulnerability index.