Determinants of neighborhood exposure to extreme heat: A spatial examination of El Paso and Juárez, 2010

Numerous studies have been conducted on the modification of local weather by the urban environment. In studying urban environmental effects on the urban heat island (UHI), researchers have investigated influences such as land use, vegetation density, topography, population density, and neighborhood socioeconomic status. Many studies have used data collected from field observations, while other studies relied solely on computer modeling. This dissertation research used a spatial analysis approach, which has been less widely employed, to investigate neighborhood level biophysical, built environmental and socio-demographic determinants of the El Paso and Juárez UHI. The research utilized inexpensive data obtained from US and Mexican government sources for the study area. Summer daytime land surface temperature (LST) was examined for the year 2010. High resolution maps of El Paso and Juárez LST were generated using remotely sensed satellite imagery. These maps enabled identification of neighborhood level variation in the intensity of the UHI. Data on previously documented predictors of extreme heat were assembled and analyzed to identify the most important influences on neighborhood level variation in LST. Findings indicate that vegetation density, land use/land cover class, and elderly population concentration were relatively important predictors of LST variation in both cities. Results for elevation, albedo, population density, educational attainment (socioeconomic status) were not stable across the analyses and between the two cities. Results also reveal that the spatial regression modeling approach explained more variation in LST than the OLS regression modeling; thus, spatial regression should be more widely used in studies of extreme heat in cities. Additionally, findings provide practical insights into mitigation strategies to protect vulnerable people from extreme heat exposure. Interventions should aim to protect vulnerable older aged people, particularly in Juárez. Additionally, urban greening programs should be implemented to mitigate extreme heat exposure in neighborhoods with high LST, high population density, and low vegetation density