Measurement, Reporting and Verification for Carbon Removal Projects

Measurement, reporting, and verification — universally abbreviated as MRV — is the technical and institutional backbone of every carbon removal project. Without robust MRV, a carbon credit is just a claim: a seller's assertion that carbon was removed, with no independent evidence to support it. With robust MRV, it becomes a verified, quantified unit of climate impact that buyers can trust and regulators can rely on. The quality, cost, and scalability of MRV systems therefore determines the quality, cost, and scalability of carbon markets themselves — which is why improving MRV is one of the most important challenges in the carbon removal sector today.

This article provides a technical overview of MRV for carbon removal projects — covering the three components of measurement, reporting, and verification, the challenges specific to different project types, and the emerging technologies and approaches that are beginning to reduce MRV costs while increasing accuracy. It is written for project developers, carbon market practitioners, corporate sustainability professionals, and policymakers who want to understand the state of the art and the path forward.

Measurement: The Foundation of Credible Carbon Accounting

Measurement in carbon removal MRV refers to the systematic collection of data that quantifies the amount of CO2 removed from the atmosphere (or prevented from being emitted) by a project activity. The appropriate measurement approach varies dramatically by project type, reflecting differences in the physical and chemical processes involved and the state of the relevant measurement science.

For engineered removal approaches like direct air capture and bioenergy with carbon capture and storage (BECCS), measurement is relatively straightforward. The CO2 flux through an industrial system can be measured directly using calibrated flow meters and sensors, achieving accuracy of better than 1 to 2 percent. This precision is a major advantage of engineered approaches over biological ones, and it is one reason why DAC credits are increasingly preferred by demanding corporate buyers. For geological carbon storage, monitoring typically involves seismic imaging, pressure and temperature monitoring at injection wells, and tracer gas analysis — well-established techniques borrowed from the oil and gas industry.

For biological removal approaches — soil carbon, afforestation, enhanced weathering, biochar field application — measurement is considerably more challenging. Soil organic carbon, as discussed elsewhere in our Insights series, varies enormously across space, requiring dense sampling networks to characterize accurately. Biomass carbon in forests must be estimated from allometric equations relating tree diameter and height to carbon content — equations that introduce their own uncertainty. Enhanced weathering projects must quantify the dissolution and downstream transport of calcium and magnesium from crushed silicate rock, which requires geochemical analysis of soil and water samples. Each of these measurement approaches has characteristic error sources that must be explicitly quantified and communicated in any honest MRV system.

The Importance of Uncertainty Quantification

One of the most important but frequently neglected aspects of carbon removal measurement is explicit uncertainty quantification. All measurements have uncertainty — the question is whether that uncertainty is acknowledged and propagated through the carbon accounting, or whether it is buried in conservative assumptions that understate both the uncertainty and the potential bias in the estimate.

In current registry methodologies, uncertainty is typically handled through "conservative accounting" — applying default factors and discount rates that are intended to ensure that the reported credit quantity is not overstated. This approach has the advantage of simplicity but the disadvantage of opacity: the reported number does not clearly convey the underlying uncertainty, making it difficult to compare across project types or to aggregate credits into portfolios with known statistical properties. A more rigorous approach — which Earthmover's platform is designed to enable — is to propagate measurement uncertainties through the calculation chain and report the final credit quantity as a probability distribution (for example, a 90% confidence interval), making the uncertainty explicit for both buyers and registries.

Reporting: Standards, Formats, and Interoperability

Reporting in carbon MRV refers to the structured communication of measurement data and carbon accounting calculations to registries, buyers, regulators, and the public. The specific reporting requirements depend on the standard or registry under which a project is registered, but all major registries require a Project Design Document (PDD) at project inception and periodic Monitoring Reports that document the measurements collected and the carbon credits being claimed.

A persistent challenge in carbon market reporting is the lack of standardization across registries and reporting frameworks. A project developer operating under Verra's VCS, the American Carbon Registry, and the Climate Action Reserve will face three somewhat different reporting templates, data requirements, and terminology conventions. This fragmentation increases the administrative burden on project developers, complicates the work of third-party verifiers, and makes it difficult for buyers to compare credits across registries using consistent metrics. Efforts to standardize carbon reporting — including work by the ISO (ISO 14064), the ICVCM, and various national and regional governments — are ongoing but have not yet achieved a unified global framework.

Data interoperability is an increasingly important aspect of carbon reporting, particularly as the market scales and more automated, machine-readable data flows become possible. Earthmover's platform is designed from the ground up with interoperability in mind — our measurement data is structured according to open data standards and can be exported in formats compatible with all major registries, as well as with corporate sustainability platforms like CDP, GRI, and emerging frameworks like the IFRS Sustainability Disclosure Standards (ISSB S1/S2). The goal is to reduce the friction between field measurement and market-ready reporting to near zero.

Verification: Independence, Accreditation, and the Third-Party Role

Verification is the process by which an independent third party — a qualified auditor accredited by the relevant registry — reviews the project developer's monitoring data and carbon accounting calculations and issues a verification statement confirming (or qualifying) the claimed credit quantity. Verification is the institutional trust mechanism that transforms a project developer's self-reported numbers into a market-tradable claim. Without rigorous, independent verification, carbon credits cannot be credibly distinguished from unverified assertions.

The standard verification process for a voluntary carbon market project typically involves a desk review of the monitoring report and supporting data, followed by a site visit to confirm that field measurements were conducted as described and that supporting documentation is in order. Accredited verification bodies must demonstrate independence from the project developer and competence in the relevant project methodology. The major registries maintain approved verifier lists, and verification bodies must pass methodology-specific competency assessments to be approved for particular project types.

A growing area of concern in verification is the adequacy of verifier capacity relative to market growth. As the number and complexity of carbon projects increases — particularly as engineered removal approaches requiring specialized technical competence scale up — the supply of qualified, accredited verifiers is struggling to keep pace. There is also a structural tension in the current verification model: verifiers are paid by project developers, creating potential conflicts of interest that mirror the problems documented in financial auditing. Emerging proposals for government-funded or buyer-funded verification pools, analogous to the Auditing Practices Board in financial markets, aim to address this structural problem.

Technology and the Future of MRV

Advances in remote sensing, sensor technology, machine learning, and data infrastructure are beginning to transform the economics and capability of carbon removal MRV. Satellite-based remote sensing can now monitor above-ground biomass changes across large forested areas at spatial resolutions of a few meters, replacing or supplementing ground-based forest inventories at a fraction of the cost. Airborne LiDAR can provide three-dimensional canopy structure data with centimeter-level accuracy, enabling biomass estimates that are far more precise than traditional allometric approaches. Field sensors for soil CO2 flux, eddy covariance towers for ecosystem-level carbon exchange, and low-cost IoT devices for biochar tracking are all expanding the monitoring toolkit available to project developers.

Machine learning is playing an increasingly important role in integrating these diverse data streams into coherent, spatially explicit carbon accounting. At Earthmover, we use ensemble learning approaches that combine outputs from multiple process-based models (RothC, CENTURY, DNDC) with satellite-derived inputs and field measurements to produce carbon stock change estimates that are more accurate and more computationally efficient than any single approach alone. These ensemble models also naturally produce quantified uncertainty estimates — one of the key features missing from current registry methodologies. As these technologies mature and costs fall, we expect MRV to become faster, cheaper, and more rigorous simultaneously — a combination that is essential for carbon markets to scale without sacrificing integrity.

Key Takeaways

• MRV is the technical backbone of carbon markets — robust MRV is necessary and sufficient for carbon credits to be credible and trustworthy.
• Engineered removal approaches (DAC, BECCS) have inherently easier measurement than biological approaches due to direct CO2 flux quantification.
• Explicit uncertainty quantification — not just conservative accounting — is essential for transparent, comparable carbon accounting.
• Reporting fragmentation across registries increases developer burden; interoperable, machine-readable data formats are the future.
• Verification capacity constraints and structural conflicts of interest are real challenges that the market needs to address as scale increases.
• Remote sensing, ML-driven ensemble modeling, and IoT sensors are reducing MRV costs while improving accuracy — enabling market scaling with maintained integrity.

Conclusion

MRV is not the most glamorous aspect of carbon removal — it lacks the engineering drama of a direct air capture plant or the ecological richness of a restored prairie. But it is, in many ways, the most important. Every climate dollar invested in carbon removal must be able to demonstrate its impact clearly, honestly, and independently. Every corporate net-zero claim that relies on carbon removal must be underpinned by measurement data that can withstand scrutiny. Building that measurement foundation — making it rigorous, affordable, and widely accessible — is the work Earthmover was created to do. We believe that advancing the state of MRV is one of the highest-leverage contributions a climate technology company can make, and we look forward to continuing to share our science and our progress with the broader community.