Many people worldwide see climate change as the top threat facing our planet.1 These concerns have prompted governments and citizens alike to ask whether planting trees is an effective way to offset their carbon footprint.
Nearly USD $300 million worth of carbon offsets were spent or traded in 2018, equivalent to 100 million tonnes of carbon dioxide. Some estimate the global carbon offset market is worth between USD $40 billion and USD $120 billion.2
Can planting trees reduce global warming?
Planting trees can undoubtedly help to reduce global warming, but there are important caveats to consider:
- We would have to plant a lot of trees
- They would have to be planted in carefully designated regions for maximum impact
- The impact may not be felt for years to come
In other words, while trees are good for the environment and important to preserve, they are not the silver bullet to combatting global warming. If the world planted trees in an area the size of the United States, it would erase decades of carbon emissions, according to a study published in 2019 in Science.3
Scientists believe that there is strong potential for trees to reduce global warming. But they also acknowledge that they are not a substitute for reducing greenhouse gas emissions.4
If everyone planted a tree, would it offset our carbon footprint?
It would help the environment enormously if everyone planted a tree. But if not done carefully, it can actually harm the environment rather than helping it5 Trees offer huge benefits by removing carbon, protecting the soil, preventing flooding and increasing biodiversity.6
But recent reports have also found that poorly planned tree planting – and on a large scale – can end up consuming large amounts of water while doing little for ecological diversity or carbon removal.7
How many trees does it take to offset one kg of CO2?
The amount of carbon dioxide that a tree can absorb depends on its species, age and location. For example, a large dense tree in a tropical forest will absorb and offset far more carbon than a young tree in a temperate climate.8
A typical mature tree can absorb up to 22 kilograms of CO2 per year, some studies have shown.9 Other scientists estimate that a tree can absorb up to one tonne of carbon over its lifetime.10
We should all certainly be planting trees to offset our carbon footprint. But it won’t stop climate change alone.
Sources
- Poushter, J. and Huang, C. (2019). Climate Change Still Seen as the Top Global Threat, but Cyberattacks a Rising Concern. [online] Pew Research Center’s Global Attitudes Project. Available at: https://www.pewresearch.org/global/2019/02/10/climate-change-still-seen-as-the-top-global-threat-but-cyberattacks-a-rising-concern/.
- Irfan, U. (2020). Can you really negate your carbon emissions? Carbon offsets, explained. Vox. [online] 28 Feb. Available at: https://www.vox.com/2020/2/27/20994118/carbon-offset-climate-change-net-zero-neutral-emissions.
- Environment. (2019). How to erase 100 years of carbon emissions? Plant trees. [online] Available at: https://www.nationalgeographic.com/environment/article/how-to-erase-100-years-carbon-emissions-plant-trees.
- Science, A.A. for the A. of (2020). Erratum for the Report: “The global tree restoration potential” by J.-F. Bastin, Y. Finegold, C. Garcia, D. Mollicone, M. Rezende, D. Routh, C. M. Zohner, T. W. Crowther and for the Technical Response “Response to Comments on ‘The global tree restoration potential’” by J.-F. Bastin, Y. Finegold, C. Garcia, N. Gellie, A. Lowe, D. Mollicone, M. Rezende, D. Routh, M. Sacande, B. Sparrow, C. M. Zohner, T. W. Crowther. Science, [online] 368(6494). Available at: https://science.sciencemag.org/content/368/6494/eabc8905.
- Saner, E. (2019). Grow your own forest: how to plant trees to help save the planet. [online] the Guardian. Available at: https://www.theguardian.com/environment/2019/sep/04/grow-your-own-forest-how-to-plant-trees-to-help-save-the-planet.
- The Royal Parks. (2019). Why are trees so important? [online] Available at: https://www.royalparks.org.uk/parks/the-regents-park/things-to-see-and-do/gardens-and-landscapes/tree-map/why-trees-are-important.
- McGrath, M. (2020). Planting new forests “can do more harm than good.” BBC News. [online] 22 Jun. Available at: https://www.bbc.co.uk/news/science-environment-53138178.
- PennisiMay. 21, E., 2020 and Pm, 2:00 (2020). Tropical forests soak up huge amounts of greenhouse gas. Climate change could end that. [online] Science | AAAS. Available at: https://www.sciencemag.org/news/2020/05/tropical-forests-soak-huge-amounts-greenhouse-gas-climate-change-could-end.
- European Environment Agency. (2012). Trees help tackle climate change. [online] Available at: https://www.eea.europa.eu/articles/forests-health-and-climate-change/key-facts/trees-help-tackle-climate-change.
- Institute, G. (2015). How much CO2 can trees take up? [online] Climate & Environment at Imperial. Available at: https://granthaminstitute.com/2015/09/02/how-much-co2-can-trees-take-up/.