Why the world needs a trillion more trees!
Six. Three. One.
We used to have about 6 trillion trees on earth. Tragically, humans have cut down half, so only 3 trillion trees remain. In a perfect world, we would bring back all these lost trees. But we also need land to grow food. So we cannot restore all 3 trillion lost trees.
But there is good news: we can restore up to 1 trillion trees without encroaching on agricultural land.¹
Once these trillion trees are fully grown, these new forests could capture between 488 and 1012 billion tons of CO2. That’s about ¼ to ⅓ of all human CO2 emissions so far (2.2 trillion tons).
But that’s not all! Restoring forests achieves much more than just tackling the climate crisis. By ensuring that these forests recover this helps us avoid the loss of plant and animal species who call these forests home, especially when tropical forests alone house over half of all species on the planet. Regenerating forests can also improve local water quality and reduce erosion.
Trees can help improve livelihoods
Additionally, bringing back trees can help build wealth in the countries of the global south. The majority of the carbon capture potential of forests exists in Latin America, Africa and southern Asia. Restoring forests in these regions has many potential benefits to society, including the creation of new economies based specifically on making restoration happen. This may lead to the generation of billions of dollars in income for national and local economies and small landholder farmers. Plant-for-the-Planet's reforestation work on the Yucatán Peninsula in southern Mexico alone created jobs for 121 people.
When trees are planted in between crops on farmland in specific ways this can increase the income of farmers by increasing crop yields. This is referred to as Agroforestry. Around 1.6 billion people rely on forest resources for their livelihood and around 1.2 billion of them use trees on farms to generate food and money.
When forest conservation and restoration is done poorly, it can also negatively affect the local population. Thus, it is essential that these programs are well managed.
None of this means that we should never harvest and use trees. 13% of global greenhouse gas emissions are caused by the production of concrete and steel for the construction industry. By building with wood instead, we can avoid these emissions. On top of that, large parts of the carbon absorbed by a tree remain in its wood once it has been harvested and converted into a chair or house, and this carbon can be stored for centuries.
Of course, we should not harvest trees from old-growth forests. But when we regrow forests, sustainable harvesting some of the trees is an important part of solving the climate crisis.
Many Methods to Regrow Forests
Bringing back these trillion trees may be a lot easier than you might think. In many cases forests can recover relatively quickly on their own, so we don’t have to plant all of these trees ourselves. In those areas, all we have to do is to stop standing in the way and nature will plant millions of trees for us. This is usually the case when the area was just deforested when the soil still contains a lot of seeds and there is a lot of intact forest nearby. However, sometimes landscapes are so thoroughly degraded that the only way to bring forests back is to plant trees. Because of this, it is important to carefully consider which restoration approaches will be the most effective in each area so we can restore forests (and a trillion trees!) as fast as possible.
In all the excitement about the power of one trillion new trees, let’s not forget how important it is to protect the three trillion that currently exist. A protected tree is better than a newly planted tree. It takes decades for a new tree to capture the amount of CO2 stored by an old tree. We still lose about 10 billion trees every year. That’s a bit more than all the trees in Germany (~8 billion).
Just Trees is not Enough
On their own, trees cannot solve the climate crisis. We must also drastically cut global carbon emissions by ending the use of fossil fuels, reducing meat consumption and more. Restoring forests can never be a substitute for reducing emissions. At the same time, the crisis is so advanced that just cutting emissions is not enough. We must cut emissions AND restore forests at the same time to prevent global temperature rise above the critical 1.5°C or even 2°C limits.
Moreover, it is not just forest ecosystems that we want to restore. To tackle the climate and the biodiversity crisis, we need to be restoring all ecosystems. Among the most important for climate mitigation are grasslands and peatlands – both of which can store large amounts of carbon when protected and restored.
"The science is simple: Trees absorb carbon dioxide. We are all impressed by Greta Thunberg, but what about Felix Finkbeiner? He’s a young German environmentalist who, at the age of 9, proposed that every country commit to planting 1 million trees and then, at 13, upped the ante and suggested at the United Nations that we target 1 trillion by 2050. Let’s start by curbing deforestation and planting as many trees as we can, as fast as we can."
– Fareed Zakaria, The Washington Post, 2022
Which country has the most trees?
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