Prioritizing mitigation efforts for intra-urban heat vulnerability using a case study of San Antonio, Texas

Many urban areas, particularly in the southern United States (US), experience extreme heat causing discomfort and illness. Heat vulnerability is not uniform across a city due to the built-environment and socioeconomic conditions, impacting some areas more than others. Therefore, it is important that heat reduction actions prioritize areas that are most vulnerable. To help ensure mitigation and adaptation efforts are most effectively targeted, analytical techniques are used to quantify vulnerability to heat. A case study of Bexar County, home to San Antonio, Texas, is used to demonstrate identification of vulnerability using high resolution land surface temperature (LST) data from the Landsat program and socio-economic data from the US Census Bureau and American Community Survey. The index is validated using chronic disease information from CDC Places as well as energy burden data. Specific heat mitigation measures may be best sited through consideration of additional variables, including characteristics of the built environment. An analysis of vulnerability by local climate zone (LCZ) is performed.<i>Implications</i>: Urban heat varies within a given metropolitan area, as does the ability of residents to adapt to extreme conditions. This variability leads to environmental justice issues. This study identifies the most vulnerable areas using readily available data sources. Using a ranking system to combine disparate metrics allows for efficient communication to allocate interventions at the local level. Findings reinforce the relationships that high building density is correlated to higher temperatures and green infrastructure and water are correlated to cooler temperatures.