Restoring forests could capture two-thirds of carbon humans having added to the atmosphere
Since the industrial revolution, humans have added around 300 billion tons of extra carbon to the atmosphere – mainly through burning fossil fuels – which is heating the planet to dangerous levels. But trees naturally remove carbon from the atmosphere, storing it above and below ground.
A new study, carried out by researchers at Swiss university ETH Zurich and published Thursday in the journal Science, has calculated that restoring degraded forests all over the world could capture about 205 billion tons of carbon in total. Global carbon emissions are currently around 10 trillion tons per year
The researchers identified ecosystems around the world that would naturally support some level of tree cover, but have become "degraded" ̵
1; deforested for timber, for example, or turned into farmland that has since been abandoned. They are currently used as urban or agricultural land, which would naturally be grasslands or wetlands, because these ecosystems can be valuable carbon stores, as well as supporting biodiversity.
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. That would give the planet more than a trillion extra trees and 900 million hectares of additional tree canopy, an area about the size of the United States.
] Efforts underway
Tree planting is no quick climate fix. It can take decades of growth for the carbon storage to reach its full potential. A more immediate benefit can come from halting deforestation, says Crowther, which costs our planet around 15 billion trees each year.
But although tree planting on such a colossal scale faces significant challenges (not least identifying who owns the land in question, and securing the rights to plant and maintain trees there), widespread are already underway.
The Australian government has announced it will plant 1 billion trees by 2030; work is underway on a "Great Green Wall" to stop the spread of the Sahara at restoring 100 million hectares of degraded land (and sequester 250 million tons of carbon), and China's anti-desertification program, also known as the "Great Green Wall , "has planted more than 50 billion trees since the 1970s. The UN-endorsed Bonn Challenge aims to reforest 350 million hectares of land globally by 2030.
Myles Allen, professor of geosystems science at the University of Oxford, said the study had overestimated the reduction an atmospheric carbon, and added: "Restoration of trees may be among the most effective strategies, but it is very far from the best climate change solution available, and a long way behind reducing fossil fuel emissions to not zero.
Crowded stressed that the potential of forest restoration must be at the expense of reducing carbon emissions. "Often when we say these papers people say this will disincentivize people cutting their emissions," he said. we must reduce emissions as much as w There are still 300 gigatons (billion tons) in the atmosphere that will keep warming the planet, and this restoration could cut fixed amounts of that. "