City to Use a Data-Driven approach to mitigate Urban Heat Island

Published on May 09, 2024

 office of sustainability    

Research partnership with UTSA to identify hottest neighborhoods in San Antonio

SAN ANTONIO (May 9, 2024) – The City of San Antonio continues to lead by example in its climate planning efforts. To expand its Cool Pavement pilot from 2023, the City partnered with the University of Texas at San Antonio's (UTSA) Sustainable Pervasive Urban Resilience (SPUR) Center to measure heat vulnerability in San Antonio and help direct resources toward the areas most impacted by extreme heat.

Explore interactive maps and research studies, learn about the City's urban heat island initiatives and prepare for summer on the SA Heat Maps StoryMap.

“Summers in San Antonio are only getting hotter – and for longer periods of time,” City of San Antonio Chief Sustainability Officer Doug Melnick said. “Some parts of the city can get hotter than others, and certain residents are more vulnerable to the rising heat. It’s critical that we direct resources to those most in need of relief.”

Inequities in heat vulnerability are driven by both socioeconomic conditions and the urban heat island effect. This effect occurs when higher temperatures in areas with more physical infrastructure, such as concrete, asphalt, and steel, absorb heat during the day and radiate it at night, leading to higher temperatures in those areas.

In 2023, three distinct research projects were launched. The Heat Vulnerability Study identified the neighborhoods most at risk for extreme heat in San Antonio. UTSA faculty used the Landsat program operated by the U. S. Geological Society and NASA to measure relative heat, then combined this data with other factors, such as income and race, to determine urban heat vulnerability across the city. The other two studies evaluated products used in the 2023 Cool Pavement pilot, measuring surface temperature, air temperature, wet bulb globe temperature (heat plus humidity), and product performance.

Among the products tested in the 2023 Cool Pavement pilot, SealMaster demonstrated the most consistent and significant reduction in surface temperatures, with an average reduction of 3.58 degrees. The maximum surface temperature reduction relative to fresh asphalt was 18 degrees. These findings provide concrete evidence of the effectiveness of cool pavement in reducing surface temperatures. SealMaster also exhibited the best adhesion strength, supporting its longevity on pavement surfaces. The GAF product, on the other hand, improved skid resistance and friction over control sites. All products tested met safety specifications and can extend the life of the pavement.

These results will support the upcoming planning and implementation of coordinated heat mitigation measures such as green infrastructure, shade structures, water features, energy efficiency, and cool materials.

For excessive heat preparedness information and resources, visit the City’s Beat the Heat website.