Climate Action

Planting trees can help the climate, but only if we also stop burning fossil fuels

A forest fire

Carbon storage in nature is likely to be only temporary because it can be lost again due to human activities or disturbances such as wildfires. Image: Unsplash/Matt Howard

H. Damon Matthews
Professor and Concordia University Research Chair in Climate Science and Sustainability, Concordia University
Amy Luers
Executive Director, Future Earth
Kirsten Zickfeld
Distinguished Professor of Climate Science, Simon Fraser University
Share:
Our Impact
What's the World Economic Forum doing to accelerate action on Climate Action?
The Big Picture
Explore and monitor how Climate Crisis is affecting economies, industries and global issues
A hand holding a looking glass by a lake
Crowdsource Innovation
Get involved with our crowdsourced digital platform to deliver impact at scale
Stay up to date:

Decarbonizing Energy

Loading...
  • Nature-based climate solutions such as reforestation aim to cut CO2 levels in the atmosphere by storing carbon in natural systems.
  • They are often seen as interchangeable with other climate actions, but they offer only temporary carbon storage, as human activities and natural disturbances can re-release the carbon.
  • Misunderstanding this could lead to more emissions and long-term warming.
  • However, these systems could play an important role in meeting climate and sustainability goals if used alongside other carbon-reduction plans.

A growing number of governments and companies are adopting net-zero greenhouse gas emissions targets. These targets often evoke nature as a way to store or remove carbon from the atmosphere to counter the climate effect of other emissions.

For example, in 2019, Prime Minister Justin Trudeau promised Greta Thunberg that Canada would plant two billion trees by 2030, and investing in nature is now a key part of Canada’s climate strategy.

Forests, peat bogs, wetlands and other ecosystems remove carbon from the atmosphere via photosynthesis and store it in leaves, trunks and roots, and in the soil. But carbon storage in nature is likely temporary because it can be lost again due to either human activities or natural disturbances.

In contrast, the climate effect of carbon dioxide emissions from burning fossil fuels is effectively permanent. If these efforts to increase natural carbon stocks are short-lived, is there any climate benefit?

Our new research suggests that temporary nature-based carbon storage can help achieve our climate goals. However, the most tangible effect — a decrease in peak warming — would only occur if we also eliminate fossil fuel emissions.

Discover

What's the World Economic Forum doing about the transition to clean energy?

Nature-based climate solutions

Nature-based climate solutions are actions that seek to reduce the amount of carbon in the atmosphere by increasing carbon storage in natural systems. Examples include reforestation, nature conservation and improved agricultural practices. They can contribute to climate mitigation by preventing emissions from human land-use activities, or by maintaining and enhancing natural processes that remove carbon from the atmosphere.

But the carbon stored in nature is unlikely to be permanently removed from the atmosphere. Disturbances like wildfire would cause carbon to be lost back to the atmosphere. Conflicting human land-use priorities can also cause previously protected natural areas to be threatened by industrial activities.

If nature-based carbon storage is temporary, then its climate benefit would also be short-lived. We need to think about nature-based climate solutions in relation to other climate mitigation efforts to understand their true benefits.

What if nature-based carbon storage is temporary?

Carbon dioxide emissions from fossil fuels have climate effects that persist for centuries. In contrast, nature-based carbon removal will only have a climate effect for as long as the carbon remains stored.

In our study, we set out to explore what temporary removal would mean for future climate. We used a climate model to simulate the climate response to temporary removal alongside two different future emissions scenarios.

If emissions continue to increase until 2040, followed by gradual decline, global temperatures would rise throughout the century. In this scenario, nature-based carbon removal would only delay the occurrence of a particular warming level. In our highest removal scenario, sequestering a quarter of current annual emissions every year until 2050 only delays the time we reach 1.5 C by a year, and 2 C by eight years.

A chart showing global temperature change
If temporary removal is combined with a strong mitigation effort global temperatures could be seen to decrease Image: The Conversation/(Authors)

However, if future emissions are decreased rapidly to net-zero by mid-century and then remain net-negative, global temperatures would peak around 1.6 C and then decline during the second half of the century. Here, temporary nature-based carbon removal would decrease the temperature peak by as much as a tenth of a degree.

This might seem small, but it is an important and tangible climate benefit that will only occur if the world also succeeds in eliminating fossil fuel carbon dioxide emissions over the coming decades.

How should we think about nature-based climate solutions?

Our results challenge the way nature-based climate solutions are discussed as a climate policy option. Nature-based solutions are often presented as one of many different ways that we could mitigate our impact on climate, and are seen as interchangeable with other climate actions. Alternately, nature-based solutions are used as offsets, explicitly held up as a substitute for other emissions reductions.

Both of these framings are problematic. If nature-based carbon storage is temporary, then its climate effect is not equivalent to avoiding fossil fuel carbon dioxide emission. This means that treating nature-based carbon storage as an alternative to other emissions reductions will, at best, delay crossing temperature thresholds. At worst, this could lead to more emissions and long-term warming.

A close view of an electric vehicle being charged
Electric vehicles charging stations are available to the public in certain areas Image: Unsplash/Andrew Roberts

On the other hand, if we take action to increase natural carbon storage in addition to ambitious emissions reductions, it could contribute to limiting peak warming. Even temporary nature-based carbon storage could have an important climate benefit.

The case for better nature conservation and stewardship

Our results reveal some of the risks of relying on nature-based climate solutions at the expense of other climate mitigation efforts. However, nature conservation and better stewardship of natural areas can also lead to other positive environmental outcomes. These environmental co-benefits, such as increased biodiversity and improved water and air quality, are also vital to climate resilience.

A wetland area
Wetlands, including those that have been damaged and destroyed by peat mining, can be restored to improve carbon storage if managed properly Image: Unsplash/Mason Field
Have you read?

If done in partnership with Indigenous and other local communities, nature-based solutions could also have positive social co-benefits such as supporting livelihoods and cultural values. Taking a holistic view of nature-based climate solutions would help to realize these multiple benefits.

It is critical that nature-based climate solutions are not presented as an alternative to other climate mitigation options. As a complementary action however, they could play an important role in meeting both climate and other sustainability goals.

Loading...
Don't miss any update on this topic

Create a free account and access your personalized content collection with our latest publications and analyses.

Sign up for free

License and Republishing

World Economic Forum articles may be republished in accordance with the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License, and in accordance with our Terms of Use.

The views expressed in this article are those of the author alone and not the World Economic Forum.

Related topics:
Climate ActionNature and BiodiversityEnergy Transition
Share:
World Economic Forum logo
Global Agenda

The Agenda Weekly

A weekly update of the most important issues driving the global agenda

Subscribe today

You can unsubscribe at any time using the link in our emails. For more details, review our privacy policy.

The ‘4 Cs’ of being a Chief Sustainability Officer

Gareth Francis

May 17, 2024

About Us

Events

Media

Partners & Members

  • Join Us

Language Editions

Privacy Policy & Terms of Service

© 2024 World Economic Forum