As the United States suffers through a summer of record-breaking heat, new research shows that temperatures on a scorching summer day can vary as much as 20 degrees across different parts of the same city, with poor or minority neighborhoods often bearing the brunt of that heat.
“The heat island effect is often characterized as the city being hotter than surrounding rural areas,” said Vivek Shandas, a professor of urban studies and planning at Portland State University, who led heat mapping projects across the country with help from community volunteers. “We’re saying it’s a little more complicated than that.”
Buildings and paved surfaces – like major roadways, uncovered parking lots and industrial zones – amplified heat, while large parks and other green spaces cooled down the surrounding areas. In cities like Baltimore and Washington, some of the hottest temperatures were recorded in dense residential neighborhoods with little tree cover and plenty of asphalt to absorb and radiate solar energy.
As climate change makes summers hotter, the health risks associated with these hyperlocal heat islands will grow.
“This is really about human health and well-being,” Dr. Shandas said. “How do we live and thrive in these places?”
