Trees, and How They Can Slow Climate Change

As human civilization arose, we needed something with which to build shelter and provide fuel for cooking and warmth. While masonry is durable and may look nice, it is expensive and heavy. We needed a light but strong material to build everything from ships to tools. The obvious choice was, and still is, wood. Wood is lighter than stone, strong, and most importantly, it is easy to work with. The issue is that,  when humans became dependent on wood, there was an abundance of it. This, coupled with humanity’s little to non-existent knowledge about greenhouse gases and the role trees play in keeping the atmosphere healthy, means we have historically cut down trees as we pleased. Because there were so many trees, there was no incentive to plant more. After all, you wouldn’t add more sand to the Sahara, would you? Unfortunately for humans, it took us over 100,000 years to realize the impact of deforestation. By that time we had already cut down almost HALF of the trees on Earth.

Approximately 30% of land on earth is currently covered with more than three trillion trees.  While that sounds like a lot, there is even more unused area. According to a team of researchers led by ecologist Tom Crowther at Swiss University ETH Zurich, there is sufficient area for another 1.2 trillion trees on Earth. His team’s calculations don’t include farmland or urban areas and limit the number of trees on grazing pastures. This means you can still enjoy the sun, buns, and burgers to which you have grown accustomed, while trillions of trees work to sequester hundreds of billions of tons of CO2 out of the atmosphere. To put that into perspective, global yearly CO2 emissions are approximately 38 billion tons. Even if the ideal spacing of trees is not achieved, there would still be a significant positive impact on climate change. 

At the current rate of $1 per tree for nonprofits such as the Arbor Day Foundation, planting trees is the most economical and most effective solution to climate change that is supported by scientific research. The added value is that, while governments around the world have programs to plant trees, such as China’s “Great Green Wall”, individuals can help, too! We don’t have to depend on world governments to take action, you can make an impact. If every person plants a few trees, we will be well on our way to regrowing the Earth. 

Written by Lucas of the Baer Engineering Green Team – Highschool Student Intern