One billion hectares of trees needed to check global warming, Science
Environmentalists estimate that global temperatures could rise 1.5° C above industrial levels by as early as 2030 if current trends continue. To address this problem, the latest report from the United Nations’s Intergovernmental Panel on Climate Change recommended adding 1 billion hectares of forests to help tackle the climate crisis.
In their recent study published on Science, ecologists Jean-Francois Bastin and Tom Crowther of the Swiss Federal Institute of Technology in Zurich and their co-authors figured out whether today’s Earth could support that many extra trees, and where they might all go. They analyzed nearly 80,000 satellite photographs for current forest coverage and categorized the planet according to 10 soil and climate characteristics. This identified areas that were more or less suitable for different types of forest. After subtracting existing forests and areas dominated by agriculture or cities, they calculated how much of the planet could sprout trees.
The analysis found there are 1.7 billion hectares of treeless land on which 1.2 trillion native tree saplings would naturally grow. Though it is impossible to have 100% tree cover on these areas, the Earth could still naturally support 0.9 billion hectares of additional forest—an area the size of the United States. The scientists specifically excluded all fields used to grow crops and urban areas from their analysis. But they did include grazing land, on which the researchers say a few trees can also benefit sheep and cattle.
Tree planting is “a climate change solution that doesn’t require President Trump to immediately start believing in climate change, or scientists to come up with technological solutions to draw carbon dioxide out of the atmosphere”, Crowther said, “It is available now, it is the cheapest one possible and every one of us can get involved.” Estimates of how much forest restoration on this scale would cost vary, but based on prices of about $0.30 a tree, Crowther says it could be roughly $300 billion.
Scientists claim that if people around the world could work together, this a billion new hectares of trees can sequester 205 gigatons of carbon in the coming decades, roughly five times the amount emitted globally in 2018, and limit global warming to 1.5° C by 2050. This idea sounds fabulous on paper. But who would be foolish enough to believe that people can actually collaborate and implement this plan?