Today is Arbor Day, a holiday that honors trees. While their beauty has been celebrated in countless poems and images over the years, trees are much more than aesthetic figures in the landscape. They are an essential part of the global ecosystem and play an important role in fighting climate change.
Trees are natural carbon sinks. They absorb and store carbon dioxide, and release oxygen via photosynthesis. Through this process, forests offset 10% to 20% of American greenhouse gas emissions every year, according to the US Forest Service. Moreover, they absorb other air pollutants and particulate matter produced by the burning of fossil fuels. Scientists say trees remove over 35 billion pounds of pollution annually in the US, directly benefiting human health.
Trees also provide shade. In cities, this helps reduce the urban heat island effect. More specifically, according to studies by the US Forest Service Center for Urban Research, neighborhoods with well-shaded streets can be 6-10°F cooler than communities without trees. This natural cooling benefit, in turn, lessens the need to run energy-consuming air conditioners during the warm summer months.
With rising temperatures leading to more heavy rain events, trees also help mitigate the impacts of flooding and landslides. Their root systems catch rainwater and reduce soil erosion. Climate Central, a non-profit environmental news organization, says trees help prevent nearly 400 billion gallons of runoff every year in the contiguous US.
So, as the saying goes “The best time to plant a tree is 20 years ago. The second best time is now.”