A University of California, Irvine study released on April 7 found that public parks in underserved areas of Los Angeles can reach temperatures high enough to cause pain or burns, mainly due to the materials used in their construction.
The findings are significant because they show how differences in park design and investment can create health risks for residents, especially during extreme heat events. The research highlights how urban planning decisions affect community safety and comfort.
Researchers discovered that parks in South Los Angeles have more artificial turf, concrete, and rubber surfaces that retain heat compared to West Los Angeles parks, which feature more natural turf and vegetation. According to the study published in npj Urban Sustainability, South Los Angeles parks averaged 105.8 degrees Fahrenheit during summer days, while West Los Angeles parks averaged about 91.6 degrees Fahrenheit. More than a third of South LA’s recreational spaces reached or exceeded the temperature linked with the human pain threshold; no such cases were found in West LA.
“Parks are often thought of as cooling refuges during extreme heat,” said Jason A. Douglas, associate professor at UC Irvine’s Joe C. Wen School of Population & Public Health. “But in some underserved communities, the parks that should provide relief are actually exposing residents to dangerous levels of heat.”
The study also found major differences in access to green space: West Los Angeles has about 117 hectares of parkland per capita compared with just over nine hectares per capita for South Los Angeles. “Residents in South Los Angeles face a double burden,” said Joshua Fisher from Chapman University’s Schmid College of Science and Technology. “They have less access to parks, and the parks that do exist are often built with materials that trap heat instead of cooling the environment.”
The research team used satellite data collected between 2021 and 2024 along with machine-learning techniques to analyze surface temperatures across hundreds of sites including schoolyards and playgrounds. Community concerns reported by local environmental justice groups helped shape the project focus.
According to the official website, University of California Irvine’s teams participate at NCAA Division I level athletics; it is part of the University of California system; it holds accreditation from the Western Association of Schools and Colleges Senior College and University Commission; it focuses on advancing knowledge through research, education and public service with an emphasis on inclusive excellence; has earned a Carnegie classification for very high research activity; and engages internationally through collaborations aimed at increasing its global influence.
Douglas said: “Parks should be part of the solution to extreme heat… If we want parks to protect communities during hotter summers, we need to invest in vegetation, shade and natural surfaces that actually cool the environment.” The researchers believe their work could inform future urban planning strategies designed to reduce heat exposure as climate change brings more frequent intense heat waves.