Cooling Boulder Through Climate Action 

The city is working to map how heat and shade are distributed across Boulder. This information will help shape how the city and its partners work to cool areas most impacted by extreme heat.

Our planet faces a climate crisis that has exacerbated inequities for low-income communities and communities of color. One of these inequities is extreme heat. As climate change worsens heat waves, people living in urban heat islands, areas that can be up to 20 degrees hotter than nearby neighborhoods, face increased health risks.

Our goal is to bring equitable cooling solutions to those facing the greatest threats from heat and to help everyone in Boulder be more climate ready.

Measuring and Mapping Heat in Boulder 

Volunteer community scientists traversed their neighborhoods in the morning, afternoon and evening on one of the hottest days of 2022. As they traveled, they collected heat data, which was later analyzed by city staff and local climate scientists.

The data shows that areas with very little vegetation and a high proportion of impervious surfaces – such as roads and parking areas – were significantly hotter, by as much as 17 degrees. On the other hand, areas with dense canopies seem to hold less heat throughout the day.

Two cars departing with heat sensors

This project was part of a larger study led by the National Oceanic and Atmospheric Administration (NOAA). Boulder was one of several communities chosen to participate in NOAA’s Urban Heat Island Mapping Campaign.

Trees Cool Cities 

Trees play a big role in keeping Boulder’s neighborhoods cool. Their canopy, the layer of leaves and branches that form treetops, provide shade and cover from the elements.

Trees also absorb heat from the air as they release moisture from their leaves, keeping water in our landscape and people cool on hot days. This is increasingly important as climate change causes longer, more dangerous heat waves.

Arbor Day, Planting, Forestry, Tree, Kids, Community

Cool Boulder: Connecting People to Climate Solutions

Cool Boulder is a campaign that equips people with the knowledge and tools needed to take affordable, impactful climate action. From neighbors to local nonprofits, Cool Boulder connects a network of local leaders excited to create a climate resilient future for all. Learn more on Cool Boulder’s website.

Try out Cool Boulder’s Tree Canopy Tool

Cool Boulder's TreePlotter Canopy tool maps the amount of tree canopy cover across the city, how it has changed over time, and where trees are needed most.

The tool is a starting place for those considering planting trees. Anyone living in Boulder can look up their address and see how much canopy cover, and therefore shade, they have over their property. The tool was created with the help of PlanIt Geo, an urban forestry consulting and software development firm.

Explore the tool online and check out Cool Boulder’s website for more information on how to use it.

The State of Boulder’s Urban Forest

Boulder’s urban tree canopy has been impacted by pests like Emerald Ash Borer and severe weather events. Boulder’s Forestry team is currently updating the city’s tree canopy data and will provide an update on its status in the coming months.

The Forestry team uses the Urban Forest Strategic Plan as a roadmap to create a more resilient, sustainable urban forest, which includes short and long-term goals to increase community safety, stabilize the urban tree canopy from losses, and improve the canopy’s overall health.

Ways to Support Our Canopy

Take Care of Existing Trees

The PLAY Boulder Foundation offers a Tree Tender program that educates and empowers community members to take care of local trees. Learn more and sign up for Tree Tender trainings on PLAY Boulder’s website.

Plant Trees

Every year, Boulder Parks and Recreation’s Forestry team teams up with the PLAY Boulder Foundation and Cool Boulder to sell trees to Boulder community members. Trees are locally grown and are suitable for Boulder growing conditions. Check PLAY Boulder and Cool Boulder’s websites for the latest information.

We have a 2023 Fall Tree Sale from now until Sept. 28. Learn more about the sale and order trees on PLAY Boulder’s website.

Request a Tree be Planted

Community members can request Boulder’s Forestry Team to plant a free street tree near their home. They’ll check each requested planting site in the fall of each year. If your site qualifies, they will plant a street tree for you the following spring for free.

Community members will need to monitor the general health of the new tree for the first few years with the Forestry team available for consultation.

Tree seedling giveaway