Making Article 6.4 work for nature and the climate

A central question is how to account for the possibility that stored carbon could be released. Forest protection and restoration can deliver significant climate benefits alongside gains for biodiversity, water and livelihoods. Yet forests also face risks from fire, drought, pests and changes in land use.

A credible carbon market must address those risks as well as value the entirety of the benefits a project delivers. How it does so will determine whether high-quality nature activities can participate and attract the finance they need.

In our white paper, Reframing Permanence for Natural Climate Solutions in Article 6.4, my co-authors and I propose an approach grounded in scientific evidence, established risk-management practices and the realities of protecting and restoring ecosystems. We examine two connected questions: how to protect climate benefits against potential losses, and how to recognize the value of carbon stored over different periods.

Managing potential losses starts with understanding uncertainty. Science helps us assess the likelihood and scale of future carbon releases. Assessments should draw on multiple sources of evidence, show a range of possible outcomes and improve as new information becomes available.

Those assessments should then inform the protections put in place. One established approach is a shared reserve of carbon credits, often called a buffer pool. Projects contribute a portion of their credits to the reserve, which can be drawn on to compensate for losses if stored carbon is released.

Like other forms of shared protection, a buffer pool benefits from spreading risk across many participants. An isolated loss at one project can be covered by the wider reserve. Requiring every project to set aside enough credits to cover its own worst-case loss would undermine that benefit and could leave otherwise credible activities unable to operate.

However, the strength of a shared reserve depends on how it is designed. A regional drought or wildfire can affect many projects simultaneously, so simply adding more projects does not necessarily provide enough protection. The reserve must be assessed against potential losses across the whole group, including severe events that affect multiple locations. Regular testing, transparent reporting and clear responsibilities are essential to establish whether it can perform as intended.

Where a buffer pool alone cannot provide sufficient protection, insurance, guarantees and dedicated funds can offer additional coverage. For example, a funded reserve could pay for replacement credits following a loss or long-term management of the carbon stock. These arrangements need clear rules governing what is covered, who is responsible and how compensation will be provided. Insurance can also help, but will not be available or appropriate everywhere, so the framework should allow combinations suited to different circumstances and timeframes.

Because risks change, these protections also need to be reviewed over time. New evidence of greater exposure may call for stronger coverage, while better management may justify changes to future requirements.

That management extends beyond financial protection. Secure land rights, community participation, benefit sharing and long-term funding can reduce the likelihood of carbon being lost in the first place. These arrangements help sustain the people and institutions responsible for protecting ecosystems, making them central to the durability of climate benefits.

Even with strong protections, the expected length of carbon storage will vary. This brings us to another key question in the paper: how should that storage be valued?

Keeping carbon out of the atmosphere for several decades can reduce warming during that period and delay climate damage. The fact that storage may eventually end does not erase the benefit it provides while it lasts. That contribution should be measured and recognized, with clear information about its expected duration and the protections supporting it.

Accuracy matters here. Carbon storage should be valued according to the climate service it provides over time. Shorter duration storage is not equivalent to permanent storage in terms of climate service, but it is not valueless. Long duration storage remains essential for balancing residual emissions at net zero, while shorter duration storage can still deliver meaningful near term climate benefits and avoid the worst effects of climate change. Critically, nature based climate action must complement rapid and sustained reductions in fossil fuel emissions.

A portfolio approach can recognize these different contributions, provided the claims made are matched to the benefits delivered. It allows valuable near-term action to contribute alongside the longer-duration solutions needed for enduring climate goals.

For Article 6.4, this means developing rules that connect sound risk assessment with credible protection against losses and transparent recognition of climate benefits over time. Such an approach can maintain high standards and ensure equity while creating workable pathways for forest protection, restoration and other natural climate solutions.

The measure of success will be whether those standards translate into climate benefits in practice. Our paper offers proposals to help achieve that, and we welcome discussion with researchers, policymakers and practitioners working toward the same goal.