Forests Can Absorb Carbon More Quickly Than Previously Thought

There’s increasing recognition of how nature can help tackle the climate crisis.  From protecting standing forests to planting new trees, forests offer significant climate mitigation benefits. Now, new research shows that letting forests regrow on their own could be a secret weapon to fighting climate change.

Experts at  the World Resources Institute (WRI), The Nature Conservancy and other institutions mapped potential rates of carbon capture from “natural forest regrowth”—a restoration method distinct from active tree-planting—initiatives where trees are allowed to grow back on lands previously cleared for agriculture and other purposes. The results, published in the leading journal Nature and available on the Global Forest Watch platform show that letting forests regrow naturally has the potential to absorb up to 8.9 billion metric tons of carbon dioxide from the atmosphere each year through 2050, while still maintaining native grasslands and current levels of food production.

That’s the equivalent of soaking up one-quarter of global fossil fuel emissions from the atmosphere every year. This is on top of the carbon sponge already provided by existing forests, which currently absorb around 30 percent of fossil fuel emissions each year.

Knowing When and Where to Let Nature Take the Lead

While decarbonization of fossil fuels and other industrial emissions remain essential pieces of the emissions-reduction puzzle, nature also has a major role to play. The United Nations declared the 2020s as the “Decade of Ecosystem Restoration,” calling for massive restoration of degraded lands to help mitigate climate change.

It’s a powerful message, but too often “restoration” is seen as synonymous with “tree-planting.” For example, a close look at national restoration commitments made under the Bonn Challenge, UN REDD+ program, Nationally Determined Contributions under the Paris Agreement, and other schemes reveals that almost half of the current land area slated for restoration is set to become plantations of commercial trees. Balancing active reforestation of commercial species with natural forest regrowth could make for a more effective approach in terms of both carbon and biodiversity.

The map generated for the recent Nature study can help identify locations where natural forest regrowth has high climate mitigation potential, to be considered alongside active tree-planting initiatives. There are many advantages to letting forests recover on their own: it’s often cheaper and more likely to benefit native wildlife. The new map, viewed alongside other information on the local socioeconomic setting and alternative uses for the land, can provide context for optimizing where to let nature take the lead.