Symposium Highlights the Crucial Role of Trees in Combatting Extreme Heat

Experts emphasize that planting and maintaining trees in urban areas is essential for reducing extreme heat, cooling cities, and preventing heat-related illnesses, especially as heatwaves become more frequent and severe.

2 minute read

September 9, 2024, 7:00 AM PDT

By Clement Lau


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As extreme heat events become more frequent and severe due to climate change, experts are urging cities to rely more on trees to mitigate rising temperatures. At a symposium titled Urban Forestry for Changing Times, over 150 arborists, scientists, and community members gathered to discuss the urgent need to plant more trees in California’s urban areas. Researchers like Edith de Guzman from UCLA emphasized that trees are not just aesthetic, but essential for cooling communities by blocking sunlight and providing evaporative cooling.

Scientific studies show that tree canopies can reduce ground temperatures by 11 to 19 degrees compared to areas without trees. Cindy Blain of California ReLeaf, a nonprofit promoting tree planting, noted that trees play a critical role in cooling urban spaces and should be strategically and carefully selected and maintained. The challenge, especially in California, is ensuring trees receive adequate water since they cannot be left unattended after planting as they might be in other regions.

As reported by Rob Hayes, experts highlighted the importance of trees in reducing heat-related illnesses and deaths, particularly in communities with fewer trees. According to de Guzman, neighborhoods shaded by trees experience lower instances of heat-related health issues, underlining the potential life-saving benefits of expanded urban forestry. As temperatures continue to rise, tree planting and care will be vital in protecting vulnerable populations from the harmful impacts of extreme heat.

Thursday, September 5, 2024 in ABC 7 Eyewitness News

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