From the floor of the UN to clothing tags in H&M, the term “carbon-neutral” has become somewhat ubiquitous in the world of the eco-conscious consumer. The concept seems straightforward enough – maintaining a balance between the carbon dioxide emitted and absorbed from the atmosphere. In practice, however, the path to carbon-neutrality is more complex. One of the more popular mechanisms through which corporations achieve carbon neutrality is carbon offsetting, the sale of certificates tied to various sustainability projects aimed at reducing the amount of carbon dioxide (CO₂) in the atmosphere –from the development and distribution of renewable technologies to nature-based solutions such as forest conservation. In fact, nature-based offset solutions could potentially account for over a fourth of the mitigative efforts required by 2030.

“Companies can purchase these certificates and claim carbon-neutrality without ever reducing their own emissions – a sort of pay-to-play pollution”

This practice, however, has been critiqued from a number of angles; for one, companies can purchase these certificates and claim carbon-neutrality without ever reducing their own emissions – a sort of pay-to-play pollution. What’s more, the projects that carbon credits fund do not always deliver their promised results. In fact, the REDD (Reducing Emissions from Deforestation and Forest Degradation) projects backed by carbon offsetting often underperform predictions. A study of a sample of REDD projects across all six continents found they prevented deforestation at a significantly lower rate than that forecast by project developers. This discrepancy undermines the credibility of the quantitative methods assessing the impacts of these nature-based solutions, rendering them risky, and thus underfunded, investments.

This is the problem that members of Cambridge faculty, among other contributors, tackle in a recently published research paper. As contributing researcher Srinivasan Keshav explains, one of the key reasons that the voluntary carbon market has been backing off nature-based solutions is a “lack of trust” in the forecasted success of these projects. He and his colleagues believe that their newly developed PACT (Permanent Additional Carbon Tonne) framework is the answer to this crisis of confidence. This new framework is unique both in its dynamic nature, with “long-term monitoring” and releases of “credits to be issued and sold at the end of each time period” to correct for over– or underestimations of a project’s effectiveness, and in its comprehensive approach – according to Keshav, no other group is simultaneously evaluating as many factors as are monitored under the PACT framework. The method also provides a means by which investors can make “like-for-like comparisons of diverse carbon projects”. Keshav stresses the importance of the transparency and accessibility of this new method, which will be open-source and unpatented in an effort to encourage those whose job it is to certify these projects to implement the PACT framework. The researchers are also in talks with the United Nations, and the Integrity Council for Voluntary Carbon Markets, aiming to disseminate their research within the carbon offsetting space.

“In a study of 89 million carbon credits produced by 18 REDD projects, 68 percent came from projects ‘that barely reduced deforestation, if at all’”

This new method does not account for all of the potential flaws in nature-based offset projects. In a study of 89 million carbon credits produced by 18 REDD projects, 68 percent came from projects “that barely reduced deforestation, if at all” – the PACT framework cannot determine whether these failures stemmed from the conceptualization or the implementation of these projects. Keshav explains that it does, however, eliminate a third unknown – the accuracy of a project’s metrics. By providing more precise means by which to evaluate its results, the PACT framework could prompt investors and project managers to investigate the factors leading to the impermanence of their projects. Keshav also furthers that while the offset market can provide opportunities to conserve tropical biodiversity, it should be treated as a “last resort” of sorts, offsetting emissions that are essentially unavoidable in the modern world, such as air travel, or as a voluntary measure along with reducing emissions, rather than to write off the mass emissions of corporations like Shell, which in 2022 alone emitted over 1.2 billion tonnes of carbon.

Does carbon offsetting represent a real, viable solution to the climate crisis? This remains unclear. While Keshav and others agree that offsetting itself should be implemented in conjunction with reducing emissions at the source, this does not always manifest in practice, a fact which has led many to view the practice as more PR than it is practicable. This is a question that, as Keshav himself readily admits, the PACT framework cannot answer. What is clear is that as the 2050 deadline for net zero emissions, as outlined in the Paris Agreement, draws ever nearer, consumers, citizens, and politicians alike must reconsider the role carbon offsetting schemes should play in the fight against climate change.