Urban Minorities Disproportionately Hit by Warming Climate

  • Tree canopies, like those seen here in Pittsburgh's Allegheny Commons park, are recommended for reducing the impact of extreme heat. Photo: J.S. Jordan

Climate change may not be color blind. Blacks, Asians and Latinos who live in urban spaces with lots of concrete and a dearth of trees could suffer disproportionately compared to their white counterparts as the earth warms and extreme heat waves worsen, according to new research.

The fix? Outside of major shifts in population distribution patterns, study authors at the University of California at Berkeley recommended tree plantings and reflective roofs and walkways. 

Bill Jesdale led researchers comparing results of the 2000 census with places where at least half the ground was covered by buildings, sidewalks, streets, and other impervious surfaces.

Nationally, non-Hispanic blacks were 52 percent more likely than their Caucasian counterparts to live in urban heat islands. For Asians, the corresponding figure was 32 percent. Hispanics were 21 percent more likely to find themselves in heat prone neighborhoods than whites.

Areas like Buffalo, Cleveland, and Detroit had the highest disparity connecting minorities to heat risk, but southwestern Pennsylvania also has a lot of room for improvement.  

This six-county map with Allegheny County in the center uses red to show the areas with very few trees.

"Downtown Pittsburgh, where the two rivers come together, you see an area where there's lots of heat risk potential," Jesdale said. "But also in some of the areas to the southwest of the downtown area, and even some of the smaller towns in the outer counties, you see downtown areas characterized as having lots of pavement and also not many trees." 



This six-county map with Allegheny County in the center uses red to show the areas with very few trees. Map courtesy Bill Jesdale.


Jesdale said, 61 percent of people would have to move for a more equitable racial and ethnic population to be in place. On the lower end, some cities are closer to the 40 percent range.

"Obviously that's not how you'd go about desegregating," Jesdale said. 

Whites who live in segregated areas tend to be at higher risk for heat-related problems. 

"That's a phenomenon we see not only with our previous work with air pollution," said Jesdale, who's explored environmental justice for many years. "What we're thinking, and we have to do more work to figure out the exact relationships here," Jesdale said. "The degree to which whites drive segregation--that is, they move out of the cities and into suburbs, you create a situation where there's less investment, or less cohesion between the neighborhoods in the city. And so, when you have a situation like trees which are a common good, there's going to be less investment in making sure everybody has access to those amenities in an area where people have really gone to some great lengths, literally in a commuting sense, to separate themselves from a city. That process of separating one's self out also dissociates them from being invested in the well-being of the area they've left behind. Again, that's hypothetical--it seems logical, but actually figuring out how to measure that and quantify that is a little more challenging." 

While one in five deaths from natural causes are caused by heat, Jesdale said there are a couple of "relatively easy things" that the Environmental Protection Agency suggests make a big difference, such as major tree plantings and using materials like concrete instead of asphalt in parking lots--lighter materials that help reflect the sun's rays.

Jesdale sees hope in the desegregating population shifts since the 1960s as well as major tree plantings in previously overlooked areas like Los Angeles, Denver, and New York City. 

But, he adds, "Trees take a while to grow, so you have to sort of think about getting those in before the major effects of climate change hit us."