
Urban heat islands trap heat, making neighborhoods like this one in Washington, D.C., even hotter on sizzling summer days. Photo by AgnosticPreachersKid, Wikimedia Commons.
By Anne Johnson
The heat of the summer is not just a nuisance but a significant public health threat. In most years, extreme heat causes more deaths than any other type of weather-related disaster. The danger is most acute for elderly people, who are more vulnerable to the effects of heat, and for people living in low-income areas, where cost barriers and features of the built environment make it harder to stay cool in hot weather.

Many underestimate the dangers of extreme heat, which causes more deaths than any other type of extreme weather. U.S. Air Force photo by Sue Sapp.

Heat maps like this one of Brookline, Mass., help city officials identify vulnerable populations and prioritize mitigation strategies.
“We are just in the beginning stages,” notes Chase Jones, City of Missoula energy conservation and climate action coordinator, “but we believe this data will inform and enhance our growth policy, building codes, infrastructure plans and urban forest management.” The project extends and enhances Missoula’s Summer Smart program, a project to prepare community members for increased heat and wildfires in summer. The challenges associated with rising temperatures may be a little different in each place, but experience shows that heat mapping is a technique that can prove useful in almost any scenario.