And there’s enough room, Swiss scientists say. Even with existing cities and farmland, there’s enough space for new trees to cover nine million square kilometres, they reported in Thursday’s journal Science. That area is roughly the size of the United States.
The study calculated that over the decades, those new trees could suck up nearly 750 billion tonnes of heat-trapping carbon dioxide from the atmosphere. That’s about as much carbon pollution as humans have spewed in the past 25 years.
“This is by far – by thousands of times – the cheapest climate change solution” and the most effective, said study co-author Thomas Crowther, a climate change ecologist at the Swiss Federal Institute of Technology in Zurich.