Trees could reduce carbon in the atmosphere to levels not seen in nearly 100 years

Early-morning joggers pass through a grove near the Presidio Golf Course in San Francisco. And if we planted a whole lot more of them in just the right places, they could reduce the amount of carbon in the atmosphere to levels not seen in nearly 100 years, researchers say. After examining more than 70,000 high-quality satellite photos of trees from all over the planet, ecologists concluded that the Earth could support 900 million additional hectares of tree cover. While international initiatives have set targets for conserving and restoring the world’s forests, researchers had never worked out the details — like what kinds of trees to plant and where to put them, said study leader Jean-Francois Bastin, an ecologist from the Swiss Federal Institute of Technology in Zurich. “In some contexts, increasing tree cover can elevate fire risk, decrease water supplies and cause crop damage by wildlife.” Karl-Heinz Erb, a social ecologist at the University of Natural Resources and Life Sciences Vienna who wasn’t involved in the research, said economic fairness should factor into decisions about where to plant trees.