We were recently inspired to write a letter to The Economist about the power of the soil to reverse climate change. We've reproduced it below, if you're interested!
Your article “Climate Change, The Necessity of Pulling Carbon Dioxide Out of The Air” (December 7th) raised the important point that it is not enough for humankind to simply reduce greenhouse gas emissions to meet the 2015 Paris Agreement’s global warming limit of 2°. We must also remove some of the carbon dioxide we have already emitted.
The article goes on to lament that we are ill-equipped to remove carbon dioxide on the scale required because we have neither the land-area to plant enough trees nor the “engineering systems to capture large amounts of carbon”. However, the article overlooks one of the biggest systems we have to remove carbon dioxide. The soil.
The Earth’s soil contains 2,500 Gigatons of carbon. That’s more than three times the amount in the atmosphere and four times the amount stored in all living plants and animals (1). It accounts for nearly 80% of carbon in the terrestrial ecosystem (2). Because it is such a huge carbon stock, even small changes can have significant results; soils already remove about 25% of the world’s fossil fuel emissions each year (3).
This new approach to farming is referred to as Regenerative Agriculture, and not only has Wholefoods Market awarded it the number one food trend for 2020 (4), but it is estimated it could sequester 23.15 Gigatons of CO2 by 2050 (5).
One of the ways Regenerative Agriculture achieves this is by increasing the capacity for photosynthesis on an area of land, enabling plants to breath in carbon dioxide and convert it to root biomass and soil-organic-carbon. This is achieved in part by rotationally grazing livestock, increasing crop diversity, and keeping the soil covered after harvesting.
Contrary to the “unfeasibly high” costs your article associates with other carbon capture systems, these techniques are affordable and achievable. Regenerative Agriculture could provide a $1.9 trillion financial return by 2050 on an investment of $57 billion (6).
Furthermore, the benefits of increased carbon in the soil can help our food systems adapt to climate change and meet the challenge of feeding a population of 10 billion by 2050 (7). We have an affordable and relatively straight-forward tool to pull carbon dioxide out of the air. A tool that need not cost the earth and is right below our feet.
(5) Project Drawdown
(6) Project Drawdown
(7) IPCC 4p100