Planting trees to reduce CO2 is one of several proposed measures that can help with climate mitigation1.
Compared to other proposed mitigation solutions, planting trees to reduce CO2 has been thought to be the ‘most effective solution’ 2. This is, in part, due to the ability to scale the solution globally: an area the size of the US is available for planting trees around the world, according to researchers3.
The UN has already announced plans4 to plant forests in cities to help make them become greener. The first potential benefit is an improvement in air quality. To add to this, it could counteract the effect of people moving to urban areas that contribute to climate change.
How Can Planting Trees Reduce CO2
Planting trees helps reduce the amount of carbon dioxide in the atmosphere as they absorb and store the gas. It is human emissions, including the likes of CO2, that scientists think are contributing to climate change5. However, CO2 is also part of the photosynthesis process for trees and plants. When combined with nutrients like nitrogen and phosphorus, CO2 helps trees grow through photosynthesis.
Estimations about how much CO2 trees can absorb vary depending on species and other natural factors. However, by planting a mix of tree species we may also increase carbon storage in forests, according to research6. One of the warnings that surround CO2 absorption estimations is around overestimating. By exaggerating realistic capabilities, proper climate action can be set back due to ‘mitigation deterrence’7.
Global Tree Planting Efforts
Yet around the world, nations are planting more trees to help grow new forests that can mitigate the effects of climate change. A worldwide planting program could potentially remove two-thirds of all the human-produced emissions from the atmosphere today, according to research8. It’s clear, that the importance of tree planting is gaining momentum and could be part of wider mitigation efforts.
Examples of planting efforts include the Great Green Wall9. This is an 8000km stretch of trees planted in Africa, growing through over 20 countries. It will be the largest living structure on the planet once complete and will be able to capture 0.5-5 gigatonnes of CO2 per year10.
In China, there are plans to increase the forest coverage rate to 26% by 2035, and to 42% by 205011. It is an effort that involves private companies too.
In addition to these countries, the UK’s leading woodland conservation charity is hoping to plant 64 million trees in the next 10 years12.
So what next?
Generally speaking, these efforts to plant trees can help reduce co2 and be an important part of climate mitigation. Yet for all the benefits of reforestation and planting programs, we must remain careful not to make trees carry the burden of tackling climate change as a silver bullet solution. In addition, it takes time for new trees to grow, so we have to wait for their ability to remove carbon from the atmosphere.
References
- What is climate change mitigation, BBC News, 13 April 2014
- Climate change: Trees ‘most effective solution’ for warming, BBC News, 4 July 2019
- Climate change: Trees ‘most effective solution’ for warming, BBC News, 4 July 2019
- Analysis: Why scientists think 100% of global warming is due to humans, Carbon Brief, 13 December 2017
- A Great Green Wall for Cities, Food and Agriculture Organisation of the United Nations
- Planting a mix of tree species ‘could double’ forest carbon storage, Carbon Brief, 22 August 2018
- Exaggerating how much CO2 can be absorbed by tree planting risks deterring crucial climate action, The Conversation, July 12 2019
- Tree planting ‘has mind-blowing potential’ to tackle climate crisis, The Guardian, 4 July 2019
- Climate Change: What is being done around the world to plant trees?, BBC News, 24 September 2019
- A Great Green Wall for Cities, Food and Agriculture Organization of the United States, 21 September 2019
- Planting trees must be done with care or it can create more problems than it addresses, Environment Journal, 4 February 2020
- Britain to go green with 64m trees to be planted in 10 years, Mirror, 1 May 2016