As record high temperatures continue to rise around the world this summer, many communities are faced with a common challenge: how to stay safe from extreme heat.
More than 1,300 deaths this summer have already been linked to the European heatwave, according to the World Health Organization. In the United States, where a heat dome has pushed temperatures into the 90s and 100s across many states, extreme heat, widely known as a silent killer, has claimed more than 21,000 lives since 1999, according to a report published by Jeffrey Howard, PhD, UT San Antonio professor of public health.
UT San Antonio researchers have been working in the San Antonio community to better understand extreme heat’s impact and to develop strategies to protect the most vulnerable residents.
In 2022 and 2023, Kristen E. Brown, PhD, assistant professor in civil and environmental engineering, and construction management, led a team of researchers from the Sustainable, Pervasive Urban Resilience (SPUR) Center, tasked by the City of San Antonio to determine what areas are most affected by extreme heat with the goal of directing resources to those most impacted.
Listen to Jeffrey Howard discuss how rising temperatures are accelerating the aging process and driving up premature mortality rates.
The team designed a Heat Vulnerability Index for the City of San Antonio to map the hottest areas of San Antonio, identifying which neighborhoods are more susceptible to extreme heat.
With the help of the Heat Vulnerability Index and maps, another team of researchers led by Esteban López Ochoa, PhD, associate professor of urban and regional planning, launched a project in the Historic Westside Neighborhood using AI and digital twin technology to evaluate housing conditions and develop solutions to better withstand extreme urban heat and build community resilience.
“Some of their homes are 120 F degrees inside when they come home from work. They must keep all their windows sealed because they don’t want anyone taking their possessions by leaving a window open,” López Ochoa said. “They come home to a house that’s just been sitting in the sun. It’s a very gruesome picture. These two invisible killers – temperature and air quality – are killing them, and that’s why they’re experiencing heat strokes.”
To better understand the vulnerabilities of the homes, the researchers created “digital twins” of the homes and their surrounding environments by placing sensors in the homes and neighborhood, allowing real-time data to be analyzed by AI.
“We are creating replicas of 10 houses that need deep housing repairs, and we are studying what housing repairs do to improve thermal comfort when you are constrained and you don’t have the money to really tear down the house and build a new one, which is the reality of many people in lower income neighborhoods of the city,” López Ochoa said.
With years of digital twin data and research from this project, the Historic West Side Resident Association’s community land trust was awarded close to $200,000 in funding to address the issues. This has a compounded impact because once the homes are up to code, residents are then able to qualify for cost-cutting weatherization programs.
“We are super happy to be able to facilitate having that funding to do some of the repairs,” López Ochoa said. “A lot of it is basic things that you would think would be easy to accomplish but are crucial barriers. If your house does not have electricity wiring up to code, then you cannot qualify for weatherization. If your foundation has issues, you cannot qualify for weatherization.”
López Ochoa and the team’s research is now expanding the digital twins and sensor work into other neighborhoods on the southside and eastside of San Antonio as they work hand-in-hand with the City of San Antonio to determine where to invest in solutions such as cool pavement, and tree planting.
“Dr. Brown and the team worked with the city three years ago to define the hottest neighborhoods, and now they define them as ‘cool neighborhoods’ where they want to put all the different mitigation strategies into,” he said.
Learn how UT San Antonio is working with San Antonio’s Historic Westside Association to strengthen the community’s resiliency to urban heat.
One of the key heat mitigation strategies that UT San Antonio and the city are working on together is implementing “cool pavement” – a water-based asphalt treatment, which reflects more sunlight while absorbing less heat and, in turn, reduces spikes in temperatures in the evening.
Neil Debbage, PhD, associate professor of political science and geography, and his team studied which cool pavement treatments would reflect the most heat on San Antonio roadways.
Debbage said that the use of cool pavement in Phoenix and Los Angeles has previously shown the product’s potential to reduce surface temperatures.
With two years of data and positive results, the San Antonio city manager allocated $5.8 million for additional investments for cool pavement.
As the growing threat of extreme heat continues around the world, UT San Antonio researchers are hoping they can better prepare the San Antonio community for the future. By connecting data science, engineering, public health and community partnerships, UT San Antonio building a more resilient community and serving as a model for other cities in addressing this critical public health issue with a variety of data-based strategies.
