Carbon accounting and climate-smart labels: It’s the wild, wild West
Yoko Kusunose, C-FARE Board Member and Professor at the University of Kentucky
Agriculture, a significant contributor to climate change, accounts for an estimated 10.5% of total emissions in the United States (EPA, 2022). While carbon dioxide is the dominant greenhouse gas emitted by other sectors, the two most significant greenhouse gases for agriculture are methane and nitrous oxide. These gasses, with a higher global warming potential than carbon dioxide, account for nearly 90% of the greenhouse gases generated directly by agriculture. The urgency of reducing agriculture’s (net) greenhouse gas footprint is evident, with the need to reduce methane and nitrous oxide emissions being as crucial as sequestering carbon in soils or generating biofuels.
However, the task is complicated by how these two gasses are generated: Methane is primarily generated through rice production, manure, and the processes in the digestive systems of ruminant animals (e.g., cattle). Nitrous oxide results from nitrogen nitrification in fertilizer applied to the soil and manure stored on farms. The emissions accounting is complicated because these are non-point sources (e.g., cows, fields, and manure management systems). Moreover, actual emissions levels can be strongly influenced by things outside the control of producers (e.g., precipitation, temperature, and soil type, in the case of nitrous oxide) as much as by things within the control of producers (e.g., feed type, manure management strategies, fertilizer application strategies, rotational choices, and fertilizer type).
Nonetheless, many private and public entities have developed programs that individual producers can use to calculate the greenhouse gas footprint—and, ultimately, the carbon credits earned by their operations. In a world in which producers can potentially get credit for implementing practices that decrease emissions and even sequester greenhouse gasses, it is critical that these many measurement tools:
Use underlying models that are consistent from one model to the next.
Have the flexibility to accommodate a growing menu of emissions-abating practices and technologies.
Be transparent and credible to producers and consumers of food, feed, and fiber.
Just as the National Organic Program Act of 1990 empowered the USDA to take the morass of ‘organic’ standards that existed in the prior decades and articulate a single list of required practices for food labeled as organic, right now, we need a mandate for an authoritative body to scrutinize models, quantify the emissions-abating effectiveness of different practices and crops in other regions, ensure consistency between emissions calculating tools, and provide legitimacy to organizations certifying farms as ‘climate-smart.’ Only then can governments scale-up incentive programs to reduce emissions, and consumers fully trust ‘climate smart’ labels on food.
