As you read this paragraph, you’re breathing, and a forest helped make it possible. That’s because forests are “the lungs of the Earth,” absorbing carbon dioxide from the atmosphere and releasing oxygen that human beings need to survive. And forests’ influence goes beyond that simple, amazing process: We also know that they play a critical role in managing clouds, wind, humidity, air quality and rainfall patterns — in ways we are just beginning to understand.
Carbon dioxide and other gases in Earth’s atmosphere trap the sun’s heat. Too little CO2, or too much of it, and the planet can’t support life. Forests help make sure the amount of CO2 in the atmosphere is just right. Over hundreds of millions of years, forests have perfected the ability to capture CO2 from the air through photosynthesis — including much of the extra carbon generated by human activities.
Forests are economic engines — with an incredible amount of horsepower. For example, almost one in four people depends on forests for their livelihoods in some way. Every year, people trade more than US$ 300 billion worth of forest products like timber, bamboo, fruits and mushrooms. And the biodiversity found within forests is key to new medical discoveries, with nature-based products accounting for an estimated 42% of the revenue generated from the world’s top-selling pharmaceuticals.
Forests are nature’s water factories. They capture, store, purify and then gradually release clean water to towns and cities located downstream. When forests are lost, these factories stop humming. Erosion and sediment increases, and water flows become more unreliable — leading to greater floods, periods of low water flow and threats to drinking supplies.