The Implications of International Greenhouse Gas Offsets on Global Climate Mitigation

The research investigates the risk of 'double-counting' international offsets, where both the buying developed country and the supplying developing country claim the same emission reduction toward their pledges. Using a spreadsheet model based on McKinsey abatement cost curves, the authors find that if offsets count twice, global abatement could be reduced by up to 1.6 billion tons CO2e in 2020. This dilution could increase the existing emissions gap by as much as 20%, potentially hindering the goal of limiting warming to 2°C. The paper compares this to a 'Buyer Only' scenario and proposes remedies such as shared crediting, partitioning eligible sectors, and implementing a common international transaction tracking mechanism.

• Double-counting of international offsets, where both the supplying developing country and the buying developed country claim the reduction, could reduce the ambition of current pledges by up to 1.6 billion tons CO2e in 2020.
• The potential dilution of pledges caused by double-counting could increase the existing 5-7 Gt CO2e abatement gap by as much as 20%, representing approximately 10% of the total abatement required in 2020 to stay consistent with a 2°C temperature limit.
• Under a scenario where offsets count twice and current mechanisms are used with lower-ambition pledges, the United States, Europe, and other developed countries would rely on offsets for over one-quarter of their abatement needs.
• In the 'Offsets Count Twice' scenario with current mechanisms and lower-ambition pledges, approximately one-fifth of total pledged abatement in 2020 is double-counted, which is equivalent to the current emissions of Japan.
• Expanding offset mechanisms (such as REDD or sectoral crediting) does not significantly increase total offset usage compared to current mechanisms, primarily due to supplementarity constraints in the EU and competition with domestic abatement in developed countries.
• Under an 'Offsets Count for Buyer Only' scenario, developing countries would need to pursue more internal abatement to meet their pledges, potentially increasing their targeted abatement by approximately 25%.

APA

Erickson, P., & Lazarus, M. (2011). The Implications of International Greenhouse Gas Offsets on Global Climate Mitigation. Stockholm Environment Institute. https://www.sei.org/mediamanager/documents/Publications/SEI-WorkingPaper-Erickson-ImplicationsOfInternationalGreenhouseGasOffsets-2011.pdf

Chicago

Erickson, Peter, and Michael Lazarus. The Implications of International Greenhouse Gas Offsets on Global Climate Mitigation. Stockholm Environment Institute, 2011. https://www.sei.org/mediamanager/documents/Publications/SEI-WorkingPaper-Erickson-ImplicationsOfInternationalGreenhouseGasOffsets-2011.pdf.

Wikipedia

{{cite report |last1=Erickson |first1=Peter |last2=Lazarus |first2=Michael |title=The Implications of International Greenhouse Gas Offsets on Global Climate Mitigation |publisher=Stockholm Environment Institute |date=March 2011 |url=https://www.sei.org/mediamanager/documents/Publications/SEI-WorkingPaper-Erickson-ImplicationsOfInternationalGreenhouseGasOffsets-2011.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{erickson2011implications, author = {Erickson, Peter and Lazarus, Michael}, title = {{The Implications of International Greenhouse Gas Offsets on Global Climate Mitigation}}, institution = {Stockholm Environment Institute}, year = {2011}, month = mar, url = {https://www.sei.org/mediamanager/documents/Publications/SEI-WorkingPaper-Erickson-ImplicationsOfInternationalGreenhouseGasOffsets-2011.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }