In the Heat of the Moment, Let’s Commit to Urban Trees

By Jad Daley, President & CEO of American Forests

In their forecasts for steaming summer heat, news reports remind us to check on elderly neighbors and friends whose health is vulnerable. Unfortunately, this good advice does not solve the underlying problem: Climate change is increasing extreme heat events and placing the most vulnerable people among us at greatest risk.

So what are long-term solutions to this crisis? You might be surprised at one answer: more trees.

To understand how trees can cool our cities you need to understand a dangerous phenomenon called the heat island effect. Heat islands form when reflected heat and light are absorbed by surfaces like sidewalks, roads, parking lots and then radiated back into the air in an oven-like effect.

Heat islands take a dangerously hot day and make it much hotter. Temperatures in these high heat areas can be more than 5° Fahrenheit warmer during the day and 22° at night as the heat absorbed during the day is radiated back at night. This unnatural heating is disastrous as summers are getting hotter and longer thanks to climate change.

That is where trees come in. A healthy urban tree canopy can give our cities the shade they need.

Properly selected and planted trees can reduce outside surface temperatures as much as 20 to 40 percent, and provide additional cooling through evapotranspiration — natural air conditioning. Larger urban forests create a pool of cooler air and spread it to nearby neighborhoods by enhancing local wind patterns.

Cooling our cities is a life or death issue. The Center for Disease Control names heat exposure as a major cause of weather-related cause of death in the US. This problem will get much worse — one study from the Rollins School of Public Health at Emory University projected a dramatic increase in heat-related deaths in eastern cities by the middle of this century.

Lower-income communities are bearing the brunt of over-heated cities as a result of the troubling negative correlation of tree canopy with income, and the fact that fewer homes in these neighborhoods have air conditioning. In the U.S., more than 13 million households do not have AC, according to the U.S. Department of Health and Human Services, including 23,000 in Washington, D.C., and 596,000 in New York City. To make this situation worse, lower-income people generally have a higher incidence of health conditions that make them vulnerable to heat.

This is why my organization, American Forests, sees expanding tree canopy to lower-income neighborhoods as a moral imperative. While many cities and their partners are making important progress, we need to do much more and faster to bring the natural cooling from trees to every neighborhood.

Investing in trees should be an easy sell. Urban trees save homeowners across the country $7.8 billion dollars in energy costs, reducing energy consumption by 7.2 percent. This is a pocketbook issue as well as a health and safety issue.

All those energy savings are huge carbon emissions savings, too, helping cities to slow climate change. Add in the fact that urban trees in the U.S. absorb almost 100 million metric tons of carbon dioxide from the air every year, and you realize that urban trees can play a big role in helping cities take action against climate change.

Larger urban forests pool cooler air and spread it to nearby neighborhoods by enhancing local wind patterns. Credit: Chuck Fazio

It is time to make this investment. This starts with federal programs like the U.S. Forest Service Urban and Community Forestry Program, state programs like California’s Urban and Community Forestry Program, and strong municipal investment. Efforts like Million Trees Miami have shown what is possible with huge ambition and the right mix of public investment matched by private sector partners, including corporations like Bank of America, The Coca-Cola Company and Bacardi.

So as we sweat our way under the current heat dome spreading across America, let’s make this the moment that we commit to expanding urban tree canopy as a top-tier priority — a moral and strategic imperative. Protecting people’s health, saving money on energy and slowing climate change? Now that is a triple-bottom line investment we all can support.

Jad Daley is president & CEO of American Forests, as well as the co-founder and current co-chair of the Forest-Climate Working Group

American Forests inspires and advances the restoration of forests, which are essential to life.