Scientific credibility for high-integrity voluntary carbon markets

High-integrity carbon credits are vital in our response to the climate crisis but high-profile research in early 2023 called into question the very basis of the voluntary carbon market (VCM). The agreement at COP29 has finally operationalised Article 6 of the Paris Agreement, and the Integrity Council for the Voluntary Carbon Market (IC-VCM) has approved three new REDD+ methodologies under their Core Carbon Principles framework indicating a concerted effort to respond constructively to criticisms and rebuild lost confidence. However, deeper and more comprehensive reforms are required to assure the market’s longer-term sustainability. The Cambridge Centre for Carbon Credits (4C) has identified several key areas where progress is urgently needed, including changes to project design, accreditation processes, and governance structures. These problems are complex, and our proposed solutions are not necessarily complete or straightforward to implement. They will require active and open collaboration between carbon accreditation and standards bodies and the scientific community. Specifically, we propose the establishment of common standards for carbon quantification and accounting, that cover additionality, leakage and permanence. These standards must avoid perverse incentives and align the motivations of all stakeholders with high-integrity outcomes. Finally, current accounting approaches tend to lay heavy financial and administrative burdens on nature-based projects and the local communities participating in or affected by them. This runs counter to the stated goal of supporting and improving financial flows to communities in developing countries.