Jul 01, 2021
By Marty Matlock, Ph.D., P.E., B.C.E.E.
Human prosperity for the past 150 years has been fueled largely by fuels stored in the earth. These geologic energy sources have expanded human well-being beyond the imaginations of our grandparents. However, as my grandfather always taught me, “ain’t nothing free.” The cost of this energy gift has been a dramatic increase in carbon moving from the geosphere to the atmosphere. This carbon is one of the most common greenhouse gases (GHG) in our atmosphere and is increasing the risk of irreversible climate change. We contributed more than 52 gigatonnes (billion tonnes) of carbon dioxide-equivalent gases (Gt CO2-eq) in 2019.
To reduce the risk of global warming to manageable levels, humanity will need to reduce annual emissions of these gases by half. The estimated total GHG emissions from all sectors in the U.S. in 2019 was 6.6 Gt CO2-eq., with U.S. agricultural production activities resulting in 0.67 Gt CO2-eq (Figure 1). This is a bit over 10% of the U.S. GHG footprint.  Putting carbon back in the soil through best management practices has the potential to store nearly 0.05 Gt CO2-eq per year.  Over time and with advancements in practices and technologies, soil sequestration could also offset emissions from agriculture and potentially other sectors (transportation, energy generation, etc.).
The coming years could see the emergence of markets for carbon sequestration in soil that actually pay for the benefits farmers provide the world each season. The transaction is pretty straightforward: farmers implement practices that sequester more carbon in soil, and industrial emitters of carbon pay the farmers for those benefits. This type of market-based emission trading helped reduce acid precipitation across the Northeastern U.S. 30 years ago. It can work to motivate innovation and transform behavior that otherwise results in environmental stress from agricultural activities. Soybean producers in the U.S. are particularly well positioned to participate in carbon markets. Modern agricultural practices—especially in soybean production—are increasing carbon sequestration in the soil and decreasing GHG emissions from crop production overall.
When farmers participate in carbon markets, they will not lose their ability to declare their practices as sustainable. Quite the contrary, by selling carbon credits, farmers are entering agreements to maintain or increase best carbon reduction practices. The carbon market simply provides a mechanism to compensate growers for the costs of implementation of these practices. A farmer who chooses to sell his or her carbon credits can not only still say—to lenders, insurers, grain buyers, and consumers—that they produced their crop sustainably, but they can tout the fact that the conservation practices on their farm helped offset or reduce global greenhouse gas emissions.
Society should not expect farmers to provide this critical ecosystem service without compensation. The atmosphere does not care which sector reduces carbon, only that annual GHG emissions are decreasing year after year. And, industries that pay farmers to increase carbon sequestration in the soil are not getting credit for the farmers’ hard work. Carbon markets create an economic incentive for companies to find ways to reduce their emissions, making GHG emissions an economic cost of doing business. When industries must pay for GHG emissions they tend to reduce carbon from all other sources over time in order to reduce costs and liabilities.
The new investments and inquiries into Carbon Markets provide opportunities for farmers to make changes in their operations while getting compensated for those changes. I estimate we have a 20-year window where increasing soil organic carbon will be compensated through carbon trading. That 20-year transition period is critical if we are to reverse the impacts of global climate change. This is why I disagree with atmospheric scientists who suggest that carbon will have to be sequestered in soil for 100 years to have an impact. The pace of adoption of renewable energy sources for the U.S. power grid and the rate of innovation in electric vehicle technology are transforming our economy. We need to stay ahead of current emissions for 20 years while the transition period plays out. My grandfather also taught me to “leave the wood stack a little higher” for the next generation. Carbon markets serves as new opportunity and value proposition for soybean farmers; now is the time to engage, ask questions and better understand our responsibilities. My father believed our best ambition is to be good ancestors. If farmers embrace these opportunities, we will have healthier soil and better technologies to successfully address the challenges that lie ahead for all of us, including our own grandkids. By 2040 they will have better choices as they work to become good ancestors themselves.
 USEPA, 2021. Inventory of US Greenhouse Gas Emissions and Sinks, 1990-2019. EPA 430-R-21-005, USEPA, Washington, DC. Accessed at: https://www.epa.gov/ghgemissions/inventory-us-greenhouse-gas-emissions-and-sinks
 Sperow, M. (2020). Updated potential soil carbon sequestration rates on US agricultural land based on the 2019 IPCC guidelines. Soil and Tillage Research, 204, 104719.