Around 0.9 billion hectares of land worldwide would be suitable for reforestation, which could ultimately capture two thirds of human-made carbon emissions.
The Crowther Lab of ETH Zurich has published a study in the journal that shows this would be the most effective method to combat climate change. The team investigates nature-based solutions to climate change.
The researchers showed for the first time where in the world new trees could grow and how much carbon they would store.
Study lead author explains: “One aspect was of particular importance to us as we did the calculations: we excluded cities or agricultural areas from the total restoration potential as these areas are needed for human life.”
The researchers calculated that under the current climate conditions, Earth’s land could support 4.4 billion hectares of continuous tree cover. That is 1.6 billion more than the currently existing 2.8 billion hectares. Of these 1.6 billion hectares, 0.9 billion hectares fulfill the criterion of not being used by humans.
The study also shows which parts of the world are most suited to reforestation. The greatest potential can be found in just six countries: Russia (151 million hectares); the US (103 million hectares); Canada (78.4 million hectares); Australia (58 million hectares); Brazil (49.7 million hectares); and China (40.2 million hectares).
The Crowther Lab uses nature as a solution to:
1) better allocate resources — identifying those regions which, if restored appropriately, could have the biggest climate impact;
2) set realistic goals — with measurable targets to maximize the impact of restoration projects;
3) monitor progress — to evaluate whether targets are being achieved over time, and take corrective action if necessary.