Solid Ground: Earth’s Soils Reveal Climate, Biodiversity & Food Security Solutions
A new mapping platform illustrates global soil carbon potential
Two of the biggest crises facing the planet—climate change and nature loss—have one hard-hitting solution in common: better food production. But until we reimagine and renew our food systems, they remain among the world’s top sources of carbon emissions and a major threat to all life on Earth.
The list of options for spurring transformation is long and, importantly, not mutually exclusive. Ideally, a host of solutions will play out differently in different places, guided by ambitious targets. My colleagues and I are exploring, researching and elevating solutions that span the breadth of the food systems, but the one that is right under our feet is also the one most often overlooked.
Soil carbon represents one-quarter of the potential of natural climate solutions—it’s 9 percent of the mitigation potential of forests, 72 percent for wetlands and 47 percent for agriculture and grasslands. What’s more, holding carbon underground in soil prevents further carbon emissions, removes carbon dioxide from the atmosphere and supplies ecosystem services to farmers.
As public and private sector leaders consider how to feed a growing population, they need effective tools to facilitate the conversation, to increase ambitions and design locally relevant solutions. Enter Soils Revealed: A new platform to facilitate understanding, discussion, ambition setting and investment for soil carbon protection and restoration.
Here are a few key ways decision-makers can use Soils Revealed to see the potential of soil carbon.
See that soils aren't static.
For far too long, most people have seen soils as a static resource, thus missing the chance to harness the full potential of soil organic carbon. Our new platform reveals how sequestered carbon stores have fluctuated over time—a first for soil science. Users can toggle between historic, recent and future scenarios on the interface to visualize three different time series data sets.
What’s more, Soils Revealed gives us a window into how distinct decisions we make about land management today could impact our future. In the map below, for instance, we see that even a business-as-usual path of “land degradation with no forest conversion” (left) could lead to the loss of carbon stocks in the near future. In the US alone, it is estimated that continuing conventional crop management will result in an additional loss of 3.54 PgC (the equivalent of 2.5 times the country’s total emissions in 2018) over the next 20 years, and a missed opportunity for climate action, nature and people alike.
But alternative and better futures are also clear. In the maps above (right) and below, we see that improved cropland management—in this case, cover cropping and minimum tillage, a basic recipe of regenerative agriculture—reveals shades of teal that represent the potential for rich new soil organic carbon stores in 2038.
See how society is managing our soils.
One key to identifying the best conservation approach for a specific region is observing how land use changes soil carbon stores. By understanding how we have lost soil carbon due to poor land management in the past, we can imagine the opportunity to rebuild this resource.
Numerous studies have estimated the total global technical potential of soil carbon sequestration in present-day croplands and pasture lands to be between about 2 and 5 Gt CO2 per year, if they’re managed right. At the upper end, that’s equivalent to the NDC ambition of the US, Indonesia, Brazil, Germany and South Africa combined.
As a soil scientist, I see opportunity all over this map. Take the midwestern United States, Europe, India and China, where croplands are extensive. Here, regenerative farming can not only store carbon in the soil, but also help clean water, make farming more resilient and improve farmers’ bottom line.
I see the potential in countries like Kenya and Mongolia, where working with communities to help manage grazing lands better can store carbon in soil across large areas, sustaining local livelihoods and protecting biodiversity while also providing climate mitigation. I can even visualize opportunities we cannot yet map at the global level when I think about places like Colombia, where farmers are planting trees and improving pastures with leguminous forage crops and live fencing, which not only helps save forests but also increases the productivity of their lands.
I also see where we can protect carbon that is already in the soil by foregoing agricultural development in certain places, which is equally important for both climate and biodiversity. By not plowing up grasslands to plant crops in Montana and the Dakotas, for instance, we can protect native plants and birds while supporting ranchers’ livelihoods as land stewards.
These sustainable alternatives for food producers are also opportunities for policymakers, who can accelerate the much-needed transformation of our food systems. With Soils Revealed, decision-makers can now home in on areas of greatest potential in their regions and support policies that encourage healthy soils—be it for the benefit of climate mitigation or more resilient farms.
See the future of soil organic carbon monitoring.
Though still in its early stages, time-series modeling using field observations and advanced machine learning will become more and more useful as data flows increase. We are currently inviting new data partnerships to enrich the effort leading up to the global rollout of this new approach in 2021.
See the big picture.
There’s so much to see when you dig deep beneath the surface. Here’s the big takeaway: More carbon exists in soils on a global scale than in all vegetation and the atmosphere combined. This means that increasing organic carbon in soil by a relatively small amount can make a large contribution to the needed carbon removal.
While Soils Revealed focuses specifically on the few scenarios that are currently possible through IPCC Tier 1 accounting—entailing the least complex methodology of three tiers—the platform provides detail down to 250 meters for some maps. Our objective is to permit even sub-national decision-makers to observe how historic losses have affected their domain, visualize soil carbon storage projections, and choose a course for sustainable management or restoration.
For example, companies can commit to reducing emissions in their supply chains, and compensate for historic emissions through carbon sequestration opportunities. Investors can catalyze soil carbon projects to help develop and accelerate action in the marketplace. In fact, in recognizing the value of soils, the private sector can help generate a win-win for their bottom line and the planet.
But governments may have the biggest role to play in harnessing the value of soils. By better understanding the potential for soil carbon storage in their regions, policymakers can set ambitious targets to maintain and increase the amount of carbon underground. Using the Soils Revealed platform can help governments achieve those targets with policy tools such as aligning agricultural subsidies toward that end, and creating stability in carbon markets through regulatory actions.
There are as many approaches to sustainable soil management as there are habitats, land uses and combinations of the latter. Harnessing even a small part of the technical potential visible in these maps will require coordinated and collective efforts by both the public and private sectors: agriculture can provide that interface.
Soil carbon isn’t a silver bullet, and it won’t be easy to transform a sector—but it is possible. Indeed, there is no panacea for the crises we’re facing; only solutions that can help accelerate our action. And in seeing soils like soil scientists—with an awareness of the multitudinous benefits of soil organic carbon—our societies can begin to build a more sustainable food system on a strong foundation, and just maybe, begin to sense the true value of the ground beneath our feet.