Moving research along in the heat of the summer, Lance Watkins, 1st place winner of the spring 2019 UCRC poster competition (graduate student category), recently shared some of his updated findings. Lance is a PhD student with the School of Geographical Sciences and Urban Planning. His research focuses on extreme heat, urban climate, and utilizing geographical information science in decision-making.
Lance’s poster titled “Comparison of Two Vulnerability Indices to Household Experience with Extreme Heat in Phoenix, Arizona, posed the following questions.
1: To what extent do measures of vulnerability based on aggregate demographic indicators correlate with measures of vulnerability based on variables at the household level?
2: Which measure of vulnerability based on aggregate demographic indicators correlates more closely with measures of vulnerability based on variables at the household level, one based on an all-hazards model, or one that is hazard specific?
In between chasing early summer storms, Lance shared the following:
We found strong relationships between several of these variables and the Heat Vulnerability Index (HVI). Households in highly vulnerable census tracts as defined by HVI were less likely to have and use central AC, less likely to have immediate access to cooler outdoor environments, more likely to use alternative cooling strategies such as window AC units and window fans, and more likely to experience heat illness requiring medical attention. The Social Vulnerability Index (SoVI) was associated with fewer survey variables. As defined by SoVI, households in more vulnerable areas in our sample were less likely to live in structurally cooler environments (e.g., limited access to basements and yards with grass), more likely to be of poorer health status, and more likely to have their home cooling be limited by the cost of repairing central AC. The differences between the two indices’ relationships with household scale variables underscores the importance of specifying the hazard of relevance when conducting a vulnerability or risk assessment.
In addition, our results suggest that, while aggregate-level vulnerability indices can help prioritize certain communities for intervention measures and future investments in structural changes in the social and built environments of cities, more precise data from households are valuable to inform the types of interventions and investments that can address the causal drivers of such vulnerability.
Lance intends to submit these findings to the journal of Applied Geography in the coming weeks.