Heat waves are more dangerous than tornadoes, statistically. They kill more people than sharks, and put more human lives at risk than blizzards, floods or lightning storms. But they lack a certain dramatic flair, making it surprisingly difficult for many people to grasp and evaluate the real danger lurking behind their devastating effects. Recognizing those risks could be a matter of life or death – especially as a changing climate is making dangerous extreme heat events more and more likely every year in the United States.
Certain people get it. Low-income communities in Dallas, Texas understand the mortal danger. So do young women in Phoenix, Arizona and black populations in Peoria, Illinois. Many people in wealthy suburbs, though, are fairly oblivious – according to new research from Peter Howe in Utah State University’s Department of Environment and Society in the S.J. and Jessie E. Quinney College of Natural Resources. Based on a national survey and high-detail maps, Howe and his colleagues found that some patterns showing whether people understood the risks of extreme heat events are explained by local temperatures, but characteristics such as economics, race and ethnicity also changed how people perceived the threat.
Areas with high-minority and low-income populations, for example, perceived greater risk. White men tended to judge the risks to be lower than others (a similar pattern exists with white men and other life dangers). Areas with older populations didn’t perceive heat waves as a bigger threat, despite increased vulnerability to the health effects of heat – older people tend not to consider themselves vulnerable, even while acknowledging that others in their age group might be more at risk.
Individuals living in high-income neighborhoods with more white residents had lower risk perceptions than those living in less-affluent areas with more minority residents. People living in cool climates often underestimated the danger of extreme heat events, even though people in colder regions are more likely to experience a heat wave. High-resolution maps show that patterns are quite complex, even within a city.
“People’s understanding changed as much between neighborhoods in the same city, in some places, as it did between states with totally different climates,” said Howe. “Socioeconomic patterns and urban geography explain more about the way that people understood the risks of extreme heat than simply looking at whether they live in a colder or hotter climate.”
This research shows that understanding the geographic diversity of perceived risks of extreme heat can help focus information for safe behaviors. Fatalities from heat exposure can often be avoided when people understand the risks, have the resources to act and take appropriate action. Avoiding danger can be as simple as increasing fluid intake, using a fan, finding a cooler location or avoiding overexertion. But if individuals don’t perceive heat exposure as a threat, they may be less likely to respond safely.
“We can use these research results to target neighborhoods and individuals who might have a lower understanding about the danger,” said Howe. “Having a sense of how a person might respond to a heat wave – in safe, or not so safe ways – allows us to share focused information about the reality of the situation.”