Nature-based climate solutions (NBS)1 represent one of the most cost-efficient methods for reducing atmospheric CO2, performing ecosystem restoration, and achieving sustainable development goals2,3. Through improved management and restoration of ecosystems, atmospheric carbon can be sequestered into terrestrial carbon pools while simultaneously protecting ecosystem services and preventing the loss of biodiversity4,5. NBS could achieve 30% of the CO2 reductions needed to keep global warming under 2°C by 20306,7,8. Carbon offsets, also reffered to as credits, are a transferable commodity that represents the removal of a tonne of atmospheric CO2. These credits have emerged as a key mechanism for directing public and private financial resources towards climate change mitigation1. The market for traded carbon credits is estimated to have grown from $295.7 million in 2018 to over $2 billion in 20219.
While growth in the carbon market is promising, concerns over issuance of credits (i.e., verifiable reductions of one tonne of atmospheric carbon dioxide which can be traded/purchased to offset producer emissions), human rights violations, and accounting errors have been raised, challenging the efficacy of nature-based carbon projects1,10,11,12,13,14. NBS-derived carbon credits are most commonly issued based on a baseline emissions scenario representing what could have occurred in the absence of the projects proposed activities (e.g. avoiding planned/unplanned deforestation, afforestation)9. This system incentivizes project developers to maximize the number of credits issued by constructing pessimistic baselines. Problematically, project developers are given considerable latitude in the choice of forecasting algorithms, which has substantial impact in the final number of credits issued9,15,16. Recently, NBS projects developed under programs and frameworks such as the Reducing Emissions from Deforestation and forest Degradation (REDD+), have been criticized and accused of issuing millions of credits with no genuine emission reductions1,12,13.
Analyzing and validating project emission reduction and baseline claims is obfuscated by the lack of freely available, standardized, georeferenced project boundaries14. Carbon credits are managed by registries, typically non-profits, that have broad discretion over data sharing. This has resulted in many project boundaries not being available for independent emissions verification12,17. Moreover, project boundaries are spread across various registries and lack standardization in their submission requirements. Many project boundaries exist only as images and maps within project documentation, rather than as independent geospatial data. These challenges make finding, consolidating, and utilizing project boundaries onerous, and are primary reasons why existing analyses of nature-based carbon projects have utilized relatively small project databases compared to the total (>600) number of existing NBS projects1,12,17. We believe it is important the carbon offset boundaries be made publicly available. In response to criticism of carbon projects, the Integrity Council for the Voluntary Carbon Market (ICVCM) was formed as a multi-stakeholder-led independent governance body designed to improve standards within the voluntary carbon market. One of the ICVCM’s Core Principles is transparency, and many protocols under which projects are developed mandate that boundary information is shared. For independent auditors to evaluate carbon projects in a comprehensive manner, spatial boundary data are required.
To ameliorate challenges associated with NBS project boundaries, we have compiled a global database of spatial boundaries from 575 nature-based forest carbon projects across 55 countries. Three project types are represented in the database: avoided deforestation (AD), improved forest management (IFM), and afforestation, reforestation, and re-vegetation (ARR). The projects in the database are listed on six carbon registries: American Carbon Registry, BioCarbon Standard, Climate Action Reserve, EcoRegistry, Gold Standard, and Verra. Boundary data were obtained from carbon registries, direct communication with project managers, and manual georeferencing. We present the systematic framework used for the compilation of this open-access database.
This effort seeks to democratizes access to project boundaries for future measurement, reporting and verification (MRV) initiatives. Additionally, this database will facilitate more comprehensive analyses of the climate benefits provided by NBS. Lastly, the development of the database aligns with the objectives outlined by regulatory and industry standards bodies, ICVCM’s Core Carbon Principles, which mandate transparency in carbon project reporting.
