Agricultural carbon measurement – why we’re not waiting for the perfect formula

Carbon measurement and verification in the agricultural environment may not yet be a perfect science, but in order to develop a robust and thriving market for carbon credits we must start now and learn from our experiences.

Environmentally minded farmers and agribusinesses using regenerative practices deserve to be financially supported in their efforts to sequester carbon. Doing so does not just improve the quality of their soil but benefits society at large by helping to draw carbon from the atmosphere. A strong market for fairly valued agricultural carbon credits would support this process to ensure it is financially viable for farmers. However, to date, uncertainties around the accuracy of soil carbon measurements on farms has hampered progress and kept the value of carbon credits low.

Our advice to any farmer or agribusiness looking to start the process of generating and trading carbon credits would be to work with an independent verifier such as Control Union, who works with robust ISO standards in order to ensure that your claims about carbon sequestration are accurate and legitimate. There are three key areas where of the process which lack consensus and clarity at present, all of which are bolstered by following an ISO14064 approach.


To guarantee that sequestered carbon is not simply released back into the atmosphere shortly after being measured in the soil, projects must address the issue of permanence. A farm’s project design document which is a necessary document in the emission verification process, must contain details of how carbon will be stored in the soil over an extended period, and how this will be secured. In addition, it should include details of a farm’s long-term management strategy, which should show methods which will retain soil carbon. Once carbon credits have been issued, there should be a process of recalculation at set periods in the future, to re-verify that the sequestered carbon has remained in the ground.


As soil carbon measurement is not a perfect process at present, carbon calculations must take into account a certain level of both quantitative and qualitative uncertainty around the accuracy of results. Following the principle of conservativeness, the potential for soil carbon sequestration should be underestimated, allowing a good margin for error against the final results. An emission reduction project should adjust the total expected level of reduced and or sequestered carbon in line with the level of uncertainty. The higher the level of uncertainty, the lower the projected amount of reduced or sequestered carbon and thus the potential value of the credits. Uncertainty can be recalibrated through recalculation during the verification project process.


Under ISO14064 project owners are required to prove additionality. Meaning they have to prove the emission reductions would not have taken place in absence of the project, for instance by substantiating the project’s lack of (financial) feasibility and demonstrating that it is not common practice in the area and/or required by local regulations.. The project owner should also check the additionality requirements of the proposed final market that credits will be sold on.

Gathering soil samples

Our validation and verification body Control Union is accredited to ISO 14065, which is the industry standard on proving competence in the validation and verification of carbon emission reductions. Their approach also follows the Kyoto protocol, itself informed by the International Panel on Climate Change. Furthermore, we work collaboratively with Cool Farm Alliance so that we can benefit from their decade of practical experience of measuring carbon on farms. This allows us the be confident in our methodology for soil carbon measurement, despite the challenges that this field of work currently faces. We are also looking forward to the introduction of a UK soil carbon code to bring a higher degree of confidence and a standardization of approach to this emerging practice.

If you would like to know more about our approach to measuring and validating soil carbon, and how carbon credits can be used to benefit farms and the companies in their supply chain please get in touch.