An integrity assessment of global forest carbon offset projects

An integrity assessment of global forest carbon offset projects | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Physical Sciences - Article An integrity assessment of global forest carbon offset projects Da Zhang, Yao An, Sheng Nie, Shize Qin, Thales A. P. West, Andreas Kontoleon, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5768592/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Forest carbon offset projects are vital for carbon removal; however, concerns over their integrity persist due to allegations of over-crediting by major carbon-crediting programs. This study evaluates the integrity of afforestation and reforestation (AR) and improved forest management (IFM) projects across six prominent carbon-crediting programs: the Clean Development Mechanism (CDM), Verified Carbon Standard (VCS), Gold Standard (GS), American Carbon Registry (ACR), Climate Action Reserve (CAR), and Chinese Certificated Emissions Reduction (CCER). We compare emissions reductions estimated using remote sensing data with those verified by third-party verifiers. Although 665 projects were initially identified, over 70% lacked sufficient data for evaluation, leaving 154 projects under the CDM, VCS, ACR, and CAR programs across 24 countries for our analysis. Our findings reveal a significant risk of over-crediting, with third-party verified credits averaging 121% higher than satellite-based estimates of emission reductions. Notably, IFM projects under the CAR program exhibited the least bias. We also observed that large-scale methodologies, verifiers with focused expertise, projects in more developed host countries, and favourable business environments were correlated with lower overestimation. Our study emphasizes the need for improved tracking and verification processes to enhance the credibility of forest carbon offset credits and foster greater confidence in natural-based carbon removal solutions. Earth and environmental sciences/Environmental sciences Earth and environmental sciences/Environmental social sciences Scientific community and society/Forestry Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.pdf Supplementary Information Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5768592","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Physical Sciences - Article","associatedPublications":[],"authors":[{"id":401803136,"identity":"07da2abd-4270-483e-ad8d-0937bf33e10c","order_by":0,"name":"Da Zhang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+UlEQVRIiWNgGAWjYDACCRDBxiDHwMDYAEIgYECUFmMekrUk9oBoorTIz25+9vBLmV36fv7DbQ+/7jgsz8DevE2CoeYOTi2Mc46ZG8ucS87tkUhsN5Y9c9iwgedYmQTDsWc4tTBLJJhJS7YxA7UwtgEZhxkbJHLMJBgbDuPUwiaR/g2osj6dh/8gWIt9g/wb/Fp4gGZKfmw7nMDDkNgGYiQ2SPDg1yIhkVMmzXDuuGHPjcQ2aca29OQ2nrRii4RjuLXIz0jfJvmjrFqevf/4M8mfbda2/eyHN974UINbCzgIeJAZbCBWAl4NwID+gc4YBaNgFIyCUYAMAIMyUH6J4MdjAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0002-0790-9298","institution":"Tsinghua University","correspondingAuthor":true,"prefix":"","firstName":"Da","middleName":"","lastName":"Zhang","suffix":""},{"id":401803137,"identity":"b03d709e-db4b-4c06-a0c1-d14d3239a46c","order_by":1,"name":"Yao An","email":"","orcid":"","institution":"Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Yao","middleName":"","lastName":"An","suffix":""},{"id":401803138,"identity":"137fa607-b389-48bf-8794-f77bb47eb33f","order_by":2,"name":"Sheng Nie","email":"","orcid":"https://orcid.org/0000-0002-5245-5619","institution":"Chinese Academy of Sciences","correspondingAuthor":false,"prefix":"","firstName":"Sheng","middleName":"","lastName":"Nie","suffix":""},{"id":401803139,"identity":"9755aeca-e04e-4fbc-8253-85d2bc708af8","order_by":3,"name":"Shize Qin","email":"","orcid":"","institution":"Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Shize","middleName":"","lastName":"Qin","suffix":""},{"id":401803140,"identity":"ffe3aa06-108d-4483-9c2e-9b76d69b3e6a","order_by":4,"name":"Thales A. 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This study evaluates the integrity of afforestation and reforestation (AR) and improved forest management (IFM) projects across six prominent carbon-crediting programs: the Clean Development Mechanism (CDM), Verified Carbon Standard (VCS), Gold Standard (GS), American Carbon Registry (ACR), Climate Action Reserve (CAR), and Chinese Certificated Emissions Reduction (CCER). We compare emissions reductions estimated using remote sensing data with those verified by third-party verifiers. Although 665 projects were initially identified, over 70% lacked sufficient data for evaluation, leaving 154 projects under the CDM, VCS, ACR, and CAR programs across 24 countries for our analysis. Our findings reveal a significant risk of over-crediting, with third-party verified credits averaging 121% higher than satellite-based estimates of emission reductions. Notably, IFM projects under the CAR program exhibited the least bias. We also observed that large-scale methodologies, verifiers with focused expertise, projects in more developed host countries, and favourable business environments were correlated with lower overestimation. Our study emphasizes the need for improved tracking and verification processes to enhance the credibility of forest carbon offset credits and foster greater confidence in natural-based carbon removal solutions.","manuscriptTitle":"An integrity assessment of global forest carbon offset projects","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-18 04:31:33","doi":"10.21203/rs.3.rs-5768592/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"236fdd0e-5564-4517-9d20-e2b577ba58d0","owner":[],"postedDate":"March 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":42822830,"name":"Earth and environmental sciences/Environmental sciences"},{"id":42822831,"name":"Earth and environmental sciences/Environmental social sciences"},{"id":42822832,"name":"Scientific community and society/Forestry"}],"tags":[],"updatedAt":"2025-03-18T04:31:33+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-18 04:31:33","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5768592","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5768592","identity":"rs-5768592","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}