Congratulations, Planet Earth–We Have Seven Times as Many Trees as Previously Thought!

image via (cc) flickr user soese

If you’re reading this, odds are pretty good that you live on planet Earth. If that’s the case, here’s some good news: Our humble home has over seven times more trees than previously thought. Yes, seven times more trees, bringing our arboreal number from 400 billion to a whopping 3 trillion. That over four hundred trees per person.

Pretty good, right?

This new estimate was reached using nearly half a million ground measurements, combined with satellite imaging, and computer models. The previous figure, by comparison, relied solely on satellite imaging, reports The New York Times. The study which lead to this stunning, seven-fold increase, was published this week in Nature. Entitled “Mapping tree density at a global scale,” the study was conducted by a team from Yale university, and spearheaded by Thomas Crowther, a post-doctoral fellow at the University's School of Forestry & Environmental Studies. Crowther became involved in the tree-counting study, after having been approached by Plant for the Planet, a global, environmental youth initiative. With a goal of planting a billion trees, the group wanted to understand what effect their efforts would have on overall C02 emissions for the planet. In order to understand the effect, Crowther realized, he’d need first to understand just how many trees there were out there to begin with.

Speaking with The Times, Crowther said: “These things really dominate our planet. They are the most prominent organisms on our planet and there are 3 trillion of them.”

Beyond simply determining a more accurate total number of trees, Crowther’s study also helped clarify where many of those trees actually exist: Primarily in the tropics, although the most dense growth takes place in Russia, Scandinavia, and North America.

image via (cc) flickr user thelightningman

Unfortunately, this new estimate is not, as it might seem, unambiguously positive. As Phys.org points out, the increase in our tree-count means that this planet’s once-total arboreal coverage (believed to have been in the neighborhood of six trillion) has still been reduced by nearly half, in large part due to human interference. But, believes Crowther, by gaining a better understanding of the current tree count, we are better prepared to understand how best to work toward improvement. He explains: “We've nearly halved the number of trees on the planet, and we've seen the impacts on climate and human health as a result. This study highlights how much more effort is needed if we are to restore healthy forests worldwide.”

[via phys.org, new york times]