The objective of this collaborative research project is to develop methods for joining social and built environment vulnerability into a single framework, and will create a prioritization framework for selecting investments in cooling infrastructure that maximize the reduction in vulnerability. The vulnerability of the United States Southwest populations to heat is a result of both a city's socio-demographic profile and the built environment, yet little is known about the latter. Prior research has largely focused on socio-demographic characteristics of population sub-groups. Emerging evidence suggests that the way in which we design our infrastructure systems may significantly affect an individual's access to cooling resources. A neighborhood that is considered socially vulnerable to heat events may be at an even greater risk if they live in buildings that warm more quickly, are in regions that may lose electricity more frequently due to generation and transmission impacts, or are not near to a community cooling center. The research team will develop novel methods for coupling socio-demographic characteristics with new infrastructure vulnerability measures to assess the nexus of coupled socio-technical risk, using Los Angeles and Phoenix as case studies. The infrastructure vulnerability indices will assess a neighborhood's access to cooling resources whether that be air conditioning, building passive cooling, access to community refuge and hydration centers, as well as disruptions of electricity supply. With the coupled socio-technical vulnerability framework, the team will develop strategies for prioritizing infrastructure upgrades.

The integrated social and infrastructure vulnerability framework will result in new methods for estimating the additional risk to heat that result from built environment characteristics, and will identify efficient cooling infrastructure investment strategies for cities to reduce this risk. The research team will convene expert panels and through their feedback will develop a guidebook that shows how cities can assess their vulnerability and which infrastructure strategies are likely to lead to the most cost-effective benefits, given particular built environment characteristics. The project will provide a guiding framework for cities to join large and complex socio-demographic and infrastructure datasets to understand which populations are most at-risk to future heat impacts and why. It will enable cities in high-risk heat regions with information and methods for understanding how to identify and mitigate future vulnerability.