A Ton is Not Always a Ton: A Road Test of Landfill Manure and Afforestation/Reforestation Offset Protocols in the U.S. Carbon Market

The authors analyzed sample offset projects across five programs—the Clean Development Mechanism, Climate Action Reserve, Chicago Climate Exchange, Regional Greenhouse Gas Initiative, and the U.S. EPA’s former Climate Leaders programme—focusing on landfill methane, manure management, and afforestation/reforestation. They found that variations in accounting boundaries, baseline methods, measurement rules, emission factors, and discounts result in significant differences in credited offsets, sometimes exceeding 50%. The paper argues for the harmonization of these protocols to improve offset quality and facilitate the linking of trading systems.

• Differences in protocol specifications for landfill methane, manure management, and afforestation/reforestation projects—specifically regarding accounting boundaries, baseline setting, measurement rules, emission factors, and discounts—result in significant discrepancies in the amount of offsets credited, which are often greater than 50%.
• The current trajectory of international climate negotiations points toward a fragmented carbon market characterized by multiple parallel emission trading and offset programs, necessitating harmonization to ensure that a "ton is a ton" across different protocols.

APA

Stockholm Environment Institute (2013). A Ton is Not Always a Ton: A Road Test of Landfill Manure and Afforestation/Reforestation Offset Protocols in the U.S. Carbon Market. https://www.sei.org/publications/a-ton-is-not-always-a-ton-a-road-test-of-landfill-manure-and-afforestation-reforestation-offset-protocols-in-the-u-s-carbon-market/

Chicago

Stockholm Environment Institute. A Ton is Not Always a Ton: A Road Test of Landfill Manure and Afforestation/Reforestation Offset Protocols in the U.S. Carbon Market. 2013. https://www.sei.org/publications/a-ton-is-not-always-a-ton-a-road-test-of-landfill-manure-and-afforestation-reforestation-offset-protocols-in-the-u-s-carbon-market/.

Wikipedia

{{cite report |author=Stockholm Environment Institute |title=A Ton is Not Always a Ton: A Road Test of Landfill Manure and Afforestation/Reforestation Offset Protocols in the U.S. Carbon Market |date=18 June 2013 |url=https://www.sei.org/publications/a-ton-is-not-always-a-ton-a-road-test-of-landfill-manure-and-afforestation-reforestation-offset-protocols-in-the-u-s-carbon-market/ |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{stockholmenvironmentinstitute2013ton, author = {{Stockholm Environment Institute}}, title = {{A Ton is Not Always a Ton: A Road Test of Landfill Manure and Afforestation/Reforestation Offset Protocols in the U.S. Carbon Market}}, institution = {Stockholm Environment Institute}, year = {2013}, month = jun, url = {https://www.sei.org/publications/a-ton-is-not-always-a-ton-a-road-test-of-landfill-manure-and-afforestation-reforestation-offset-protocols-in-the-u-s-carbon-market/}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }