Toute l'actualitéAs the voluntary carbon market continues to mature and transparency requirements increase, the demonstration of additionality has become a decisive criterion for ensuring the integrity of carbon sequestration projects. In the field of Nature-based Solutions, where biophysical and socio-economic dynamics vary significantly from one territory to another, this requirement translates into the need for robust methodological tools capable of distinguishing the intrinsic effect of a project from the natural evolution of ecosystems. The VM0047 methodology developed under the Verra standard addresses this need by introducing the performance benchmark, a mechanism designed to assess the actual contribution of a reforestation project to carbon sequestration.
Reforest’Action has developed an ambitious operational application of this benchmark, relying on remote sensing data to strengthen the rigor of the assessment. By anchoring the analysis in the observed dynamics of vegetation, this approach makes it possible to establish the additionality of carbon sequestration achieved by projects and thereby provide companies and investors with a high level of assurance regarding their climate impact.
A Central Mechanism for the Integrity of ARR Projects
The Requirement for Demonstrable Additionality
Additionality is a core determinant of the integrity of a carbon project. A carbon credit can only deliver environmental value if it corresponds to carbon sequestration that would not have occurred in the absence of carbon finance.
For forest projects—which may span tens of thousands of hectares, encompass multiple land-use types, and be influenced by a wide range of local socio-economic, political, and regulatory factors (such as agricultural land profitability, public policies supporting reforestation, or local land tenure dynamics)—demonstrating additionality represents a particular challenge.
Assessing each situation individually may lead to heterogeneous evaluations and difficult-to-compare arbitration across projects. To address this complexity while ensuring a consistent and coherent assessment framework, the VM0047 methodology under the Verra standard, which applies to afforestation, reforestation, and revegetation projects, relies on a standardized reference mechanism: the performance benchmark.
Defining the Project’s Actual Contribution to Carbon Sequestration
Within VM0047, the performance benchmark serves as a reference threshold to determine whether a project is genuinely additional. In other words, it aims to quantify the actual contribution of a project to carbon storage at the parcel level over time, taking into account changes in land use across the project area. The contribution of a forest project to increased carbon sequestration is not the same in a region experiencing agricultural abandonment and the expansion of fallow land as it is in a region subject to agricultural intensification.
“The performance benchmark makes it possible to compare the overall regional trend in carbon sequestration with that of the implemented project,” explains Hugo Treuil-Dussouet, Geomatics and Remote Sensing Analyst at Reforest’Action. “This method allows us to determine the level of contribution a project makes to carbon sequestration on the parcels concerned. For example, in a parcel that has been reforested at 100% as part of a carbon project, the project may in fact only contribute to 70% of the carbon sequestration, given that the remaining 30% would have been sequestered through vegetation development even in the absence of the project.”
Applying the Performance Benchmark at Reforest’Action
In line with the Verra methodology, Reforest’Action relies on remote sensing to observe vegetation dynamics. A donor area is first defined in order to delineate a sufficiently large zone characterized by legal, ecological, and management conditions similar to those of the project area. Within this zone, control plots are identified, which together constitute a dynamic baseline representing the natural evolution of vegetation cover in the absence of a reforestation project.
The comparison between the sequestration trajectories of project plots and those of control plots is based on a Stocking Index, specifically the Normalized Difference Fraction Index (NDFI). This indicator, derived from spectral unmixing, makes it possible to assess biomass levels, forest cover, and vegetation density. Observed at multiple points in time, it is used to establish an average trajectory reflecting vegetation dynamics. When the sequestration curve of the project plots exceeds that of the control plots, the additional sequestration can be attributed to carbon finance.
This analysis is updated every five years, in line with the verification cycles required under VM0047, in order to ensure that the benchmark remains aligned with actual field conditions and accurately reflects project performance over time.
A Response to Market Expectations
The approach developed by Reforest’Action to apply the performance benchmark under VM0047 directly contributes to strengthening the environmental and methodological integrity of certified projects. By relying on a robust biophysical proxy and regular updates, this method provides essential safeguards for the high integrity of the carbon credits generated through our projects.
Reducing Uncertainty and Ensuring Transparency
Defining a donor area and control plots anchors the benchmark in a real, rather than theoretical, representation of vegetation evolution in the absence of a project. This approach offers two key advantages: it avoids biases associated with models or economic assumptions that often underpin ex ante additionality analyses, and it provides a dynamic baseline based on vegetation trajectories observed through remote sensing, thereby reducing scientific and methodological uncertainty. Reforest’Action thus strengthens the credibility of reported sequestration and limits the risk of overestimation.
The use of the NDFI, an indicator derived from spectral unmixing, ensures a standardized measurement of biomass and vegetation density. This tool offers several key benefits for carbon integrity:
- it relies on satellite data that are accessible, traceable, and verifiable;
- it enables continuous and consistent measurement of project performance;
- it enhances objectivity by removing reliance on declarative or subjective interpretations.
The use of a stable and recognized spectral proxy increases the transparency of the MRV (Monitoring, Reporting & Verification) process and facilitates the reproducibility of results by third-party auditors.
Demonstrating the Impact of Carbon Finance
By comparing the sequestration curves of project plots with those of control plots, it becomes possible to demonstrate in a tangible way that the project’s sequestration trajectory exceeds the natural dynamics of local vegetation, and that this additional performance is directly attributable to carbon finance. This makes it possible to move from presumed additionality—typical of ex ante projection approaches—to additionality demonstrated through observed data. This distinction is critical for strengthening the credibility of carbon credits in the eyes of companies and investors.
Integrating Environmental and Socio-Economic Changes
Updating the benchmark every five years, in line with the Verra standard’s verification cycles, ensures that the assessment remains aligned with real-world conditions. This periodic update prevents outdated or non-representative trajectories from continuing to serve as references, allows for the integration of changes in climate, land use, and management practices, and enhances the accuracy of sequestration estimates over the full life of the project. The benchmark is therefore not static; it is adaptive, which increases the robustness of the MRV framework and limits the risk of cumulative overestimation.
Providing a Framework Aligned with Current Market Expectations
Reforest’Action’s approach fully addresses the growing expectations of the carbon market:
- environmental integrity, through real and verifiable measurements;
- comparability between projects, through a reproducible and standardized methodology;
- robust governance, through process auditing and transparency of the data used.
In a context where financial actors and companies require high levels of assurance before committing to sequestration projects, this approach represents a significant strategic advantage.
Integrating the performance benchmark within VM0047-certified projects represents a key lever for ensuring their integrity and credibility. By mobilizing an approach based on the observation of vegetation trajectories and the regular updating of data, Reforest’Action enhances the precision of sequestration monitoring and demonstrates in a tangible manner the additional impact of carbon finance. This methodological rigor, supported by the use of a spectral proxy and dynamic control plots, is fully aligned with the evolution of international standards and responds to the growing expectations of economic actors engaged in the climate transition.
In a market where trust is built on the ability to measure, verify, and compare climate benefits, the approach developed by Reforest’Action provides a structured, transparent, and scientifically grounded framework. It also confirms the central role that remote sensing technologies can play in improving the quality of Nature-based Solutions, paving the way for safer, more ambitious, and truly transformative investments for ecosystems and the climate.