By Sophie Scherger
BERLIN – Healthy soil is indispensable to life on Earth, sustaining nearly 60% of all living species. As the second-largest carbon reservoir after oceans, soil is also among our planet’s most important natural assets in the fight against climate change.
But the world’s soils are under immense strain. Droughts are increasingly turning fertile land into deserts, while pesticide use drastically reduces soil biodiversity, threatening our ability to produce healthy food. As high-quality agricultural land becomes scarcer, conflicts over shrinking topsoil – critical for crop growth – are intensifying.
The Heinrich Böll Foundation’s recent Soil Atlas highlights the many ways we are losing the ground beneath our feet. The current industrial agriculture system has been a major driver of soil degradation, accelerating biodiversity loss and depleting vital carbon reserves. Yet despite its impact, the agriculture sector has made little progress in advancing climate goals. Its global greenhouse-gas emissions have remained largely unchanged over the past decade.
As countries worldwide set new emissions-reduction targets under the 2015 Paris climate agreement, it is clear that achieving real emissions cuts will require developing strategies to reduce the agriculture sector’s carbon footprint.
One approach touted as a potential solution is “carbon farming,” which uses market incentives to reward farmers for storing carbon in their soil. By adopting practices like planting cover crops, farmers can earn certificates for increasing carbon storage. These certificates can then be sold as carbon credits in voluntary or government-mandated markets, providing farmers with an additional income stream.
This concept has gained traction in both public-policy circles and the private sector. Fertilizer and pesticide companies like Yara and Bayer have already rolled out their own certification programs, while major agriculture producers such as Canada and Australia have integrated these credits into their markets. The European Union is also developing a certification program for carbon farming, and global carbon markets are expected to follow suit.
Unfortunately, the newfound popularity of carbon farming risks perpetuating the false notion that emissions reductions and soil carbon storage are interchangeable. Even if we accept this premise, developing a system to offset emissions through carbon storage is extremely difficult. For such a system to be effective, storage must originate from a change in farm practices and be measurable and secure for at least a century.
But given that carbon stored in soils is inherently unstable and can easily be re-released into the atmosphere by droughts, floods, or shifts in farming practices, long-term storage remains highly unreliable.
Previous attempts to address this instability in other natural reserves have been unsuccessful. For example, reserve credits set aside to offset unintended carbon releases from forests in California are being depleted faster than anticipated after the intense wildfires there. And there has been little interest in credits with expiration dates, which would require buyers to renew them periodically.
While it is possible to measure the carbon stored in soil, doing so is neither simple nor cheap. The accuracy of these measurements depends on several factors, including sampling depth, location, and timeframe. Alternative methods, based on limited sampling or mathematical models, have failed to overcome measurement challenges.
Since prices for soil-carbon credits have been too low to cover the costs of changing agricultural practices, farmers are unlikely to embrace them. In response, European regulators have opted to make credit generation easier, rather than adjusting price incentives, thus compromising the system’s integrity.
Beyond methodological challenges, carbon farming can serve as a smokescreen for the livestock industry. Industry groups claim that carbon storage in grasslands can offset methane and nitrous-oxide emissions. But this scenario is unrealistic, given that it would require vast amounts of grassland. It is well established that the most effective way to reduce livestock emissions is to cut livestock numbers and consumption of meat and dairy.
The carbon-market approach views maintaining soil health and reducing emissions as an either/or choice. In reality, both are necessary, as healthy soil is essential for food production. The Intergovernmental Panel on Climate Change has found that sequestering carbon in soils – or anywhere else – cannot replace emissions reductions. Targeting emissions reductions, rather than relying solely on soil credits, could have the additional benefit of weakening the appeal of controversial technologies that aim to remove carbon from the atmosphere.
Simply put, a market-based approach to carbon storage cannot deliver the transformative change we need. We cannot offset our way out of the climate crisis. Instead, we should redirect public funds currently spent on agricultural subsidies to investments that improve soil health and support farmers as they undertake the transition to a climate-resilient food system.
Copyright: Project Syndicate, 2024.
