California schools Face Increasing Heat as Tree Canopy Declines
A recent study from UC Davis’s Urban Science Lab reveals a concerning โฃtrend: California school districts โคareโค experiencing a decline in tree canopy cover, leaving students increasingly exposed to extreme heat. Between 2018 and 2022, the average tree canopy lossโ across urban school districts was less than 2%, but some areas, notably in the Central Valley, saw considerably higher reductions โ- up to 25% in some cases. Tulare โCounty experienced the most considerable losses, while Imperialโฃ Countyโค showed โคgains.
The research, a collaborative effort between UC Davis, UC Berkeley, and UCLA, highlights the vulnerability โคof California’s students to rising temperatures exacerbated by climate change. The study is funded by the U.S. Forest Service and supported by Green Schoolyards America’s California Schoolyard โTree Canopy study.
Researchers, led by Alessandro Ossola, an associate professor of โขplant sciences at UC Davis who directs the Urban Science Lab, are actively measuring the impact of this โคloss.They are assessing the extent to which high temperatures areโข impacting students’ well-being. This past summer, the team measured tree canopies and maximum temperatures at playgrounds, basketball courts, โคsoccer fields, โand other outdoor spaces โฃat elementary schools statewide.
Currently,tree canopies cover only 4% to 6%โข of the average California school campus. This leaves approximately 5.8 million K-12 public school students โexposed to direct sunlight during breaks and outdoor activities. Researchers mapped tree cover and heat fluctuations throughout the day โคat schools in both inland and coastal โregions of Northern and Southern California, โขutilizing a mobile sensor cartโ named MaRTyna to โขgather data on mean radiant temperature and other key metrics.
“Most schools โare actuallyโ a nature desert,” ossola stated, emphasizing the importance of nature exposure for children’s development, including skill-building, microbiome health, and environmental awareness. “Trees are a hidden asset and an underutilized asset.”
The study underscores theโข urgent needโ to increase tree canopyโฃ in schools with limited shade and to protect existing treesโ in areas experiencing loss, particularly as extreme heat and droughtโ conditions are expected โto intensify with climate change.
This report is adapted โfrom a feature storyโฃ published byโ theโฃ UC Davis College โคof Agricultural and Environmental Sciences: “Researchers Measure Schoolyard Heat One Step at a Time”.
