Could planting trees halt climate change?
Scientists have calculated that the cheapest and most effective way to fight climate change may be to plant trees—a trillion of them. Because trees soak up atmospheric carbon dioxide, a major contributor to global warming, researchers from the Swiss Federal Institute of Technology decided to examine what would happen if saplings were replanted on lands where forests had been cleared. They concluded that the planet could support an extra 2.2 billion acres of tree cover, an area almost the size of the U.S. Those new forests, the researchers say, would remove about two-thirds of the roughly 330 billion tons of carbon pumped into the atmosphere by humans since the Industrial Revolution. Reforestation is “the top climate change solution in terms of carbon storage potential,” co-author Thomas Crowther tells Vox.com. Crowther and his colleagues identified six countries where the majority of the reforestation would need to take place: Russia, the U.S., Canada, Australia, Brazil, and China. And, they say, trees need to be planted sooner rather than later, because climate change could soon make it impossible for forests to thrive in some areas, such as the tropics. Other climate scientists say the global reforestation plan is too ambitious to be realistic, and that governments should focus on reducing carbon emissions, not coming up with ways to scrub greenhouse gases from the atmosphere. ■