Sommer, Allan (RTI International, 3040 Cornwallis Rd, Research Triangle Park, NC, 27709; Phone: 919-316-3993; Fax: 919-541-6683; Email:


Alternative Approaches to Quantifying and Reporting Carbon Sequestration Projects: The Case of Afforestation


Allan J. Sommer *, Brian. C. Murray


Project-based approaches to GHG mitigation in general and carbon sequestration in particular are gaining ground as a potentially effective means to reduce GHGs and achieve other environmental and economic objectives.  In the U.S., voluntary programs such as the DOE 1605(b) and the California Climate Action Registry are encouraging the reporting of project-based actions.  As a result, programs such as these and other overarching initiatives such as the World Resources Institute/World Business Council on Sustainable Development (WRI/WBCSD) are developing guidance for quantifying and reporting the contributions of these actions to GHG reductions.  


A key technical issue in project quantification and reporting is the establishment of a project baseline, which estimates net GHG effects that would occur without the project. Baselines may be used to determine if project GHG reductions are additional to what would happen under business as usual.  For the GHG protocols presented, to the extent that they address baseline-setting, consider two baseline-setting approaches, project-specific and performance standard.  Our analysis evaluates usefulness of the two methods for evaluating carbon sequestration in agriculture, land use change, and forestry (AgLUCF). Given the spatially explicit nature of AgLUCF projects, the project-specific approach focuses on the characteristics of activities largely within project boundaries in determining the baseline.  In contrast, the performance-standard uses regional information on the behavior of cohort groups to gauge what other landowners might do under conditions similar to the project.


We evaluate specific, though hypothetical, afforestation projects in the Lower Mississippi River Valley, USA, to “road test” the alternative protocols.  Additionally we identify data requirements, assess the pros and cons of each approach, and quantify the difference in the potential GHG benefits generated under each approach for dealing with issues such as baseline-setting, treatment of leakage, and permanence.  Comparing the quantification and reporting guidance of the protocols will identify key factors that affect the magnitude of reported sequestration benefits and the potential for misstating the GHG implications of a project under certain circumstances.