Study: How many trees are left on Earth?
Saturday, September 5, 2015, 12:22 PM - Tree-lovers (and anyone who enjoys breathing), we have good news and bad news about how many trees are still standing on Earth.
First the good news: According to a new study led by researchers at Yale University, there are about three trillion trees on our planet, about seven and a half times more than previous estimates.
That's "trillion" with a "T" and it's such a staggering number even the researchers were surprised.
"I don’t know what I would have guessed, but I was certainly surprised to find that we were talking about trillions," Thomas Crowther, the lead author of the study, said in a statement from the university.
The researchers used a combination of satellite surveys, forest inventories and supercomputer models to come up with a map of where all the trees are:
Image: Yale University
They modelled it down to a square-kilometre level, and it is impressive, not only to see where all the forests are (look at how thickly forested Canada is aside from the North, southwestern Ontario and the St. Lawrence, and the southern Prairies), but where they aren't.
Here's the bad news we promised: The huge amount of trees on the planet is around half what it was before mankind figured out how to make tools.
Not only that, Crowther says, human activity has the biggest impact on tree numbers, and deforestation, changes in land use and forest management make for a loss of more than 15 billion trees a year.
"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," said. "This study highlights how much more effort is needed if we are to restore healthy forests worldwide."
The Yale study has been published in the journal Nature.
SOURCE: Yale University