How Heat waves are getting longer and more intense in Southern Californialack of shade is becoming a serious public health problem, but large areas of Los Angeles remain vulnerable.
Research shows that shaded areas can have a “heat load” – a combined measure of temperature, humidity and wind. up to 35–70less degrees than nearby areas exposed to the sun. A quality shade can also Reduce UV exposure by up to 75% and help prevent 50% of emergency room visits during heat waves.
Ahead of the 2028 Olympics and other global events coming to Los Angeles, a coalition of universities, nonprofits and local agencies launched ShadowLAinitiative to expand cooling infrastructure throughout the city. Under the leadership USC Dornsife Public Exchange – a program that connects researchers with policy makers – and UCLA Luskin Center for InnovationThe project focuses not only on where shade is needed most, but also on how to create it so that it will last a long time.
“The climate that made Los Angeles so idyllic and attractive in the 20th century is now turning deadly for many of our neighbors,” said Edith de Guzman, an associate professor in the UCLA Department of City Planning and co-director of the project. “And at the same time, our city is shrinking because we can use less of it. There are fewer and fewer places where we can be safely and thermally comfortable.”
ShadeLA brings together agencies such as the Los Angeles County Office of Sustainability, the County Transportation Authority, and a network of nonprofits including City Plants, North East Trees and TreePeople.
“We need a lot of different people coming together to work on this issue,” said Monica Dean, director of the climate and sustainability practice at USC Dornsife Public Exchange and co-leader of the project. “And we don’t just have to add shadow either. We also need to take care of and support the shadow we have.”
Unlike many other past campaigns to green Los Angeles, such as Los Angeles' Million Treeswhose goal was to plant a million trees in a decade—ShadeLA has not set a strict target for the number of trees or structures it hopes to build.
Instead, the initiative emphasizes what it calls “shade quality,” using new high-resolution mapping tools to calculate what useful ground-level coverage people actually experience in public spaces where they walk, wait, or congregate. This data helps participants decide which projects to implement to achieve the greatest impact: whether it's planting a tree with a large canopy on one corner, redesigning a bus stop to provide more overhead canopies, or creating a pop-up cooling zone in a high-traffic area.
Such projects are especially important as Los Angeles begins preparations for the 2028 Olympics, which will bring millions of additional people to the city. “We're really looking at the 2028 Games and the mega-events leading up to them as a leverage point. We hope that these events… will push Los Angeles to do the right thing and build on its legacy,” de Guzman said.
This approach is based on USC Urban Trees Initiativea five-year research effort that mapped shaded areas across the city and identified specific areas where new trees could have the greatest impact. In Lincoln Heights and Boyle Heights, for example, the study identified space for nearly 100 additional trees at Hazard Park, more than 50 at Murchison Street Elementary School, 22 at Hillside Elementary School and more than 180 at the Ramona Gardens public housing complex, where residents live near busy freeways with little natural surface. These areas, according to the researchers, are among the areas with the greatest need for landscaping because they combine high foot traffic, low canopy and limited access to air conditioning.
TreePeople, a longtime leader of Southern California's urban forestry movement, has outlined plans to plant thousands of new trees in the region—not as part of a citywide quota, but as part of ShadeLA's broader program to provide high-quality, long-lasting shade. The group also organizes volunteer tree planting events and conducts workshops to teach people how to help trees survive.
As Marcos Trinidad, TreePeople's senior director of forestry, noted, planting trees alone won't solve the problem unless the city and Olympic organizers commit resources to long-term care.
“What's missing now is a firm commitment from the city and the Olympic organizers – a number, a budget, something we can use,” Trinidad said. “Without this, we risk ending up in the same situation we've seen before, where trees are planted without the resources to ensure their survival. We don't want to just put numbers on paper – we want a living, strong canopy.”
Still, he's optimistic about ShadeLA. “We hope that the collaboration will continue and be a means that we can use to increase the shade of the canopy after the Olympics,” Trinidad said.
Ultimately, project leaders hope this initiative will change the way people see the city, forcing them to recognize shade not only as a comfort, but as an important infrastructure for the health and sustainability of a community.
“I really want us to start thinking like Los Angeles residents — to train our eyes to see our neighborhoods differently and see where there are opportunities” for shade, de Guzman said. “Because the truth is that each of us has some agency and some ability to command this civic resource.”
