A new study suggests that trees are our most powerful weapon in the fight against climate change. Massive restoration of the world’s forests would cancel out a decade of carbon dioxide emissions.
In the past, scientists had assumed that there are fewer trees in the world than there actually are. Ecologist Thomas Crowther and his colleagues have published research indicating that there are three trillion trees in the world. This is seven times more than in previous estimates.
Using satellite imaging and other techniques, the same research identifies areas where more trees could be planted. It does not include areas that are currently occupied by cities or agriculture. The research identifies room for an additional 1.2 trillion trees in parks, woods, and abandoned lands.
Dr. Crowther contends that undervaluing trees means scientists have also been massively underestimating the potential for forests to combat climate change.
For example, Project Drawdown is a group that compares the merits of different emission-cutting techniques. With the method it uses (there are others) it currently places onshore wind power and improved recycling of refrigerators and air conditioners at the top of its list of emission cutting techniques. According to Dr. Crowther, if the planting of trees were undertaken, it would far outstrip the carbon dioxide cutting of these two.
The British publication The Independentrecently featured a story on Dr. Crowther’s research. To read the whole thing, go to https://www.independent.co.uk/environment/forests-climate-change-co2-greenhouse-gases-trillion-trees-global-warming-a8782071.html. To see the research paper itself, go to .https://www.nature.com/articles/nature14967. Warning: the paper is dense and technical and may tell you more about trees and mapping than you really wanted to know.