The boundless benefits of trees in cities like Austin

Editor’s Note: The video above shows KXAN News Today’s top headlines for May 3, 2023.

AUSTIN (KXAN) — America’s urban population is growing rapidly. In fact, 80% of the U.S. population is located within a city.

This means a large population of people are increasingly more vulnerable to the extremes of climate change, including heatwaves, flooding rain and poor air quality (events that often get exacerbated in a growing city).

Cities, however, are stepping up to mitigate and adapt to the negative impacts of climate change through planting more trees and greenery and turning toward more sustainable practices.

Our partners over at Climate Central analyzed 242 cities across the U.S. to show how trees located in urban areas benefited each city and to what degree they had on mitigating the impacts of climate change. Their analysis was done in conjunction with the U.S. Forest Service’s i-Tree data.

Cities suffer from the urban heat island effect, where the downtown area is hotter than the surrounding (less urban) areas. We experience this firsthand in Austin. This is the result of pavement, cement and buildings absorbing the sun's energy during the day. The dense infrastructure is not only responsible for retaining heat and creating this urban heat island effect, but it also increases the risk of flooding. Cement, paved surfaces and lack of soil obviously can't store any water. So flooding storm-water runoff becomes common during heavy rainfall events.

Trees planted in urban areas however have been found to help alleviate these problems as well as provide a multitude of benefits to a city and its encompassing community.

Trees reduce heat

Trees provide a canopy of shade that can cool surrounding areas as much as 10 to 20 degrees. Cooling surface temperatures help decrease a multitude of health hazards including heat-induced illnesses during hot summer months.

Trees reduce flooding and storm-water runoff

Leaves and branches that accompany a tree canopy help slow down falling rain. The roots in the ground help to absorb and soak up much of the water on the ground. This combination helps to reduce flooding and storm-water runoff.

Trees improve air quality

Leaves within trees help absorb many gases that are harmful to human lungs including ozone and nitrogen dioxide. Trees can also help block larger particles in the air as well.

Trees remove and store CO2

Trees remove CO2 and other harmful greenhouse gases from the atmosphere. They store the carbon in their leaves, trunks, branches, and roots. Less carbon in the air can help slow the impacts of global warming.

Trees can improve your mental health

Studies have linked trees and time spent in nature to a number of physical and mental health benefits. 

Here is what Climate Central found for the city of Austin in particular:

1. 1664 million gallons of storm runoff is avoided per year because of our trees.
2. 15 million pounds of air pollution is absorbed per year because of our trees.
3. 800 thousand tons of co2 carbon pollution is removed per year because of our trees.