Heat, Trees, and Your Health

Urban Forests Mitigate Urban Heat

Urban forests create healthy communities and trees are two times more effective at mitigating the challenges of urban heat than other identified strategies. Trees are considered an important part of our communities’ infrastructure and provide many economic, social, environmental, and health benefits when properly placed, planted, and maintained.

Urban Heat, Trees, & Your Health

Texas Trees Foundation is committed to furthering education about the relationship between urban heat and trees to human health. Outdoor workers, children and the elderly are particularly at risk and vulnerable this time of year as urban heat is a major public health issue.

Heat exposure has been shown to exacerbate underlying chronic conditions, including pulmonary, cardiovascular, and kidney conditions. Additionally, epidemiological data shows that motor vehicle collisions, violence, suicide, and workplace injuries increase during extreme heat events. Trees have been shown to be vital for reducing heat stress and decreasing the size and effect of the urban heat island.

Below is a list of resources to understand the connection between extreme heat and health - stay tuned for more information to be posted throughout the summer.

Texas Trees Foundation's Urban Heat Island Management Study

Texas Trees Foundation’s Urban Heat Island Management Study from August 2017 is a year-long study of the impacts and implications of air temperatures at the neighborhood level. Most notable among them: Dallas is heating up faster than every city in the country except for Phoenix.

URBAN HEAT ISLAND MANAGEMENT STUDY (.PDF)

Dallas Tree Equity Planting Map

Increasing the number of trees across Dallas is vital to keeping our neighborhoods cool, healthy, and beautiful. But currently, too many of our historically underserved and overlooked communities lack even an adequate tree canopy.

DALLAS TREE EQUITY PLANTING MAP (.PDF)

In the News

April 2024: Heat caused record-high rates of health emergencies in some parts of the US last year, CDC report shows
April 2024: These are the neighbourhoods in most urgent need of trees
September 2023: 'Climate breakdown' alert as air quality dips during heatwaves: UN chief
August 2023: Dallas’ heat islands need scientific solutions
July 2023: Inmates are dying in stifling Texas prisons, but the state seldom acknowledges heat as a cause of death
June 2023: Duke Launches Heat Policy Innovation Hub to Safeguard Communities
June 2023: Heat-related illnesses increase dramatically in Dallas County as temperatures climb
May 2023: Buckle up because El Niño is almost here, and it’s going to get hot

Things you need to know:

Heat

What is an urban heat island?

What is extreme heat and why is it on the rise?

What is the difference between surface temperature and air temperature?

What is the heat index?

Heat + Trees

Greening strategies

Trees, grass, and other vegetation in cities provide a wide range of environmental and public health benefits, one of which is a cooling of the ambient air. Green plants can lower air temperatures through the processes of evaporation (the transfer of water to water vapor on plant surfaces) and transpiration (the transfer of water to water vapor in plant cells), referred to in concert as “evapotranspiration,” which makes use of solar energy to convert water to water vapor, thus limiting the quantity of solar energy available to increase surface temperatures. A single oak tree transpires up to 40,000 gallons of water a year, while an acre of corn transpires up to 3,000 to 4,000 gallons of water a day [26], returning large quantities of water to the atmosphere and lowering air
temperatures in the process (Figure 1.4).

Source: p. 15 of Urban Heat Island Study

How do trees cool the air?

What benefits do trees provide?