Mapping Heat Inequality

A new mapping tool underscores inequities in infrastructure that lead to higher rates of heat-related illnesses in low-income neighborhoods.

2 minute read

July 14, 2022, 8:00 AM PDT

By Diana Ionescu @aworkoffiction


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A new mapping tool from UCLA that tracks heat-related emergency room visits in Los Angeles County “highlights a stark disparity between wealthier, leafier neighborhoods and those that are home to fewer trees, more concrete and higher occurrences of underlying health issues.” Hayley Smith reports on the map’s findings for the Los Angeles Times. “Although extreme heat has become the leading cause of weather-related deaths in the United States, a Times investigation found that such deaths are chronically undercounted.”

According to the map, some parts of Los Angeles see as much as four times as many emergency room visits due to extreme heat. “The parts of L.A. County that show higher rates of ER visits during heat days include the South L.A. corridor down to the ports, the San Pedro area, and the northwest Valley, especially San Fernando and Pacoima, said Eisenman, who is also a professor at the UCLA Fielding School of Public Health.”

A county Climate Vulnerability Assessment released last fall found that extreme heat could increase by as much as ten times in the next two decades. “[David Eisenman, co-director of the UCLA Center for Public Health and Disasters] said the findings in L.A. County are in some ways not surprising in that they echo the ‘decades of redlining’ that have led to differences in shade, access to air conditioning and even base-line health levels in some L.A. communities. Redlining was the institutional practice of denying homeownership and financial services to residents based on race.” Eisenman also points out that heat exacerbates underlying conditions like diabetes and heart disease.

The city of L.A.’s new “chief heat officer,” Marta Segura, says her office is working to create an early warning system for heat waves and implement long-term strategies for reducing heat exposure, including planting more trees and updating building codes.

Tuesday, July 12, 2022 in Los Angeles Times

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