Studying Who Heat Islands Hurt And Where They Live

September 27, 2013

This past summer was the hottest ever in Phoenix, according to the National Weather Service.

Chester Mikhail Chester is an assistant professor of civil, environmental and sustainability engineering at ASU. (Photo by Nick Blumberg-KJZZ)

During the height of the heat, few places in the U.S. have it worse than the Valley, and if you are in downtown Phoenix, it is going to be a lot worse than it is out in Buckeye or Gold Canyon. Researchers are starting to look at who is most affected by the urban heat island effect and how the neighborhoods they live in could make that heat less severe.

Climate change and the greenhouse effect usually are not controversial among scientists, but among the general population of the country, a lot of people are skeptical, but even if you do not believe in global warming, testing the urban heat island effect is an experiment you can perform yourself just by driving around the Phoenix area. So, when things get really bad when a heat wave strikes a city who is most affected?

“Senior adults, people who are living in poverty, people who are living alone, especially when they’re older and lower income," said David Eisenman, director of the Center for Public Health and Disasters at UCLA.

Eisenman spent a lot of time looking at populations most vulnerable to extreme heat  like the people he just mentioned plus non-English speakers and people with chronic diseases. He and colleagues at UCLA and Arizona State University have been given nearly $500,000 from the National Science Foundation to study rising temperatures in two sprawling metro areas, Los Angeles and Phoenix.

The group includes Mikhail Chester, assistant professor of civil, environmental, and sustainability engineering at ASU. He focuses on things like building materials.

“Certain types of people in neighborhoods might actually be in buildings that are more likely to warm faster," Chester said.

So, the research will drill down to the census tract level to study...

“Not only things like air conditioning, but the building stock itself," Chester said.

They will also examine whether neighborhoods have cooling and hydration centers and...

“Does anybody really have access to them?” said Chester

Chester said researchers understand a lot about what demographic factors contribute to higher rates of hospitalization and death during heat waves, and they are starting to look into what kinds of materials can mitigate heat, things like reflective pavement and roofing.

“So what seemed to be missing was this piece of how does infrastructure contribute to social vulnerability?” Chester said.

Now, the researchers will try to answer that question by asking who is most likely to show up in a hospital during heat waves, and what kind of building do they live in? When energy demands climb, does every neighborhood get an equal amount of power?

After those questions get answered, the ASU-UCLA team wants to present its findings to local governments. Brian Stone said there is growing momentum to address rising urban temperatures.

“When we look at a phenomenon like the heat island effect, this tends to be a lever that cities can pull all on their own," said Stone.

Stone is an associate professor of city and regional planning at Georgia Tech. He is in the last few months of a heat island study that looked at how to reduce future heat-related deaths in Atlanta, Philadelphia and Phoenix. Stone said filling in empty holes in our sprawling metro area, and planting more native vegetation...

“ combination with cool paving and roofing materials where it’s feasible can offset between about a third and a half of the projected additional deaths over time," explained Stone.

And Eisenman said that is especially important, because the people most affected by extreme heat are often hidden.

“If you’re older, low-income, living by yourself, you’re often not connected to your neighbors, not connected to people in the neighborhood, and if you’re hospitalized, nobody knows it. We don’t necessarily see the victims of heat waves like we see the victims of hurricanes and earthquakes," Eisneman said.