The Implications of International Greenhouse Gas Offsets on Global Climate Mitigation

This research paper analyzes how the accounting of international greenhouse gas (GHG) offsets affects the integrity of global climate mitigation pledges. Using a spreadsheet model based on marginal abatement costs, the authors examine scenarios where offsets are either double-counted (credited to both the buyer and seller) or counted only for the buyer. The study finds that double-counting could significantly dilute the ambition of current pledges, potentially reducing global abatement by up to 1.6 billion tons of CO2e by 2020, thereby increasing the gap to meet 2°C warming targets.

• Double-counting of international offsets, where both the supplying developing country and the buying developed country claim the reduction, could reduce the effective ambition of current pledges by up to 1.6 billion tons of CO2e in 2020.
• The potential for double-counting could increase the existing 5 to 7 Gt CO2e abatement gap (needed to stay on a 2°C pathway) by as much as 20%, or dilute the total required 2020 abatement by approximately 10%.
• Under a scenario where offsets count twice and current mechanisms are used with lower-ambition pledges, developed countries are forecast to use 1.2 Gt CO2e of offsets, with the U.S., Europe, and other developed nations using offsets for over 25% of their abatement needs.
• If offsets count only for the buyer, the total offset usage is estimated to be lower (0.9 to 1.0 Gt CO2e) because developing countries with pledges would need to pursue more internal abatement to compensate for the credits sold.
• The authors identify several remedies to prevent double-counting, including counting offsets for the buyer only, sharing crediting between buyer and seller, or partitioning emission sources so that only those not covered by developing country pledges are eligible for offsets.
• Complementary tools to ensure offset integrity include the use of a common international transaction tracking mechanism, stringent and consistent offset protocols to reduce non-additionality, and new mechanism designs that partition credit based on contribution.
• Non-additional offsets (credits that do not represent real reductions) pose a significant risk; for example, if BAU wind and hydro power in developing countries were credited, it could result in approximately 0.6 Gt CO2e of non-additional offsets by 2020.

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} }