As D.C. (and the planet) continues to heat up, NBC Washington asked American University researchers and yours truly, “Which trees are the coolest?” To find out which trees fare best downtown, check out this feature by Mark Segraves and Claire Savage from NBC4:
Using satellite imagery and infrared cameras, American University scientists are researching which tree species are the best at cooling us off.
“Trees are our natural air conditioning system,” said Professor Mike Alonzo, who leads the AU research team.
The findings will help determine which trees hold the most water and keep their leaves the longest in a downtown environment, where miles of sidewalk bake in the sun amidst rising global temperatures.
“But then you have to think, all of the people coming in every day to be in the city are experiencing massive amounts of heat, and with our climate getting warmer, you’re gonna have more heat exhaustion, more heat stroke and a lot of potential health issues,” said Dr. Jessica Sanders, an urban forestry researcher at Casey Trees, a nonprofit aiming to protect trees in the District.
AU researchers are taking measurements in city parks and using satellite imagery to assess which trees should be planted where.
“We want trees that are gonna be robust to the hot, noisy, chaotic environment in which they live,” Alonzo said.
Satellite imagery also reveals tree bloom progression of trees throughout the year, which will help predict peak bloom for Washington’s famous cherry blossoms.
The District is working to increase the number of trees in the city. If you’re looking to cool off in your own yard, Casey Trees will determine the best tree for your space and plant it, all for free.