The New York Times reported
For the first time, scientists have sought to quantify this thought experiment. How many trees could be planted on every available parcel of land on Earth, where they could go, and what impact could that have on our survival?
They concluded that the planet could support nearly 2.5 billion additional acres of forest without shrinking our cities and farms, and that those additional trees, when they mature, could store a whole lot of the extra carbon — 200 gigatons of carbon, to be precise — generated by industrial activity over the last 150 years.
Read full story at Restoring Forests Could Help Put a Brake on Global Warming, Study Finds – The New York Times