The benefits that trees provide for water quality alone are numerous. In addition to the ways they improve water quality and protect our waterways, trees provide many other kinds of ecosystem services. Many of the benefits that trees provide are connected to processes that slow down and mitigate the effects of climate change.
In recent years, trees have received a lot of attention as solutions for the climate crisis (see Best way to fight climate change? Plant a trillion trees and Tree-planting has ‘mind-blowing potential’ to tackle climate crisis). But just how effective a strategy is tree planting in combating climate change?
How Trees Help Fight Climate Change
Trees provide a lot of services. But,unfortunately, we can’t plant our way out of climate change; tree planting is not a silver-bullet solution (Can Planting a Trillion Trees Stop Climate Change? Scientists Say it’s a Lot More Complicated).
However, increasing tree canopy is touted as a critical “nature-based solution” or “natural climate solution.” What exactly does that mean?
We like this description from The Climate Reality Project:
“Natural climate solutions are non-technological ways we can reduce emissions and remove
carbon pollution from the atmosphere and store it in natural ecosystems like forests, grasslands,
and coastal wetlands. They present an opportunity to leverage the natural world around us to
restore the balance we’ve upset by pumping carbon pollution into the atmosphere.”
There are two angles to how trees can help:
- By slowing down the rate of carbon dioxide released into the atmosphere (a process referred to as carbon sequestration); and,
- By decreasing heat and flooding risks, therefore mitigating the effects of climate change that we are already experiencing and that are predicted to intensify in the near future.
We all learned in grade school that trees take in carbon dioxide and release oxygen (nice clean air for us to breathe!). Where does that extra carbon go in the meantime? Trees use carbon to grow, and it is “accumulated in the form of biomass, deadwood, litter, and in forest soils” (UNECE).
When trees are capturing and storing (“sequestering”) this carbon, that means a reduced amount of carbon dioxide, a greenhouse gas, in the air. Definitely a win!
Keeping It Cool
One of the ways trees create a more resilient environment – one that can bounce back from hardships and disasters more quickly – is by lowering local temperatures and keeping us cool. Trees make a more comfortable and safe environment by providing shade and through the cooling effects of evapotranspiration.
A simple experiment with an infrared thermometer clearly maps out how much cooler it feels in the shade in summer. Check out the plot points below for temperatures recorded on a hot, unshaded sidewalk versus under the cool canopy of a large tree.
Trees also keep us cool through a process called evapotranspiration, where water that a tree has soaked up through its roots is released back into the atmosphere through a tree’s leaves. You can think of evapotranspiration almost like a tree sweating – except the “sweat” cools the surrounding air.
Being really hot in the summer is uncomfortable, but it can also be dangerous. Heat-related illnesses cause more deaths than any other weather event, such as floods or tornadoes (The Increasing Death Toll in the U.S. From Extreme Heat). Trees help reduce these risks of extreme heat.
Trees as Public Infrastructure
With all these services trees provide, they can even be considered public infrastructure, a critical function for a city, like water pipes and roads. As infrastructure, trees reduce risks associated with climate change – in particular, the risks from the increase of extreme weather events linked to climate change. More intense and frequent rainfall events are expected in Middle Tennessee as the climate continues to warm up (read more in the Cumberland River Compact’s blog post What Climate Change Means for Nashville, Tennessee and How You Can Help).
Ponding and flooding occurs when too much rain falls too fast for the ground to soak up. Trees help mitigate local flooding by slowing down rain as it falls. Some rain doesn’t even end up making it to the ground, as it evaporates off the leaves. Trees also soak up lots of water (in one growing season, a large 100-foot tree soaks up 11,000 gallons of water – Water & Forests, USDA). By protecting us from these effects of climate change, trees serve as important neighborhood defenders.
Using Trees as a Natural Climate Solution in Nashville
While tree-planting isn’t the only strategy needed to combat climate change, growing our city’s canopy can keep more carbon dioxide out of the air and protect us from the effects of climate change by lowering local temperatures and decreasing flooding risks.
For Nashville teens interested in natural climate solutions like tree-planting, as well as other strategies, registration is currently open for the Cumberland River Compact’s Youth Climate Summit on Saturday, March 4. The summit is a place for high-schoolers throughout Davidson County to learn, share, connect, and to take action against climate change.
This year, attendees will have the opportunity to apply for funding to implement a climate action project in their school, neighborhood, or community. Funds from Nashville SC will help students make their climate visions a reality. The climate action projects are a perfect opportunity for students interested in implementing tree-based climate solutions to their own communities! Click here to learn more about this funding opportunity.