Emulating absent land processes reduces carbon budgets in CMIP6 models

Emulating absent land processes reduces carbon budgets in CMIP6 models | 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 Article Emulating absent land processes reduces carbon budgets in CMIP6 models Spencer Liddicoat, Chris Jones, Lina Mercado, Eddy Robertson, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9203584/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 The Transient Climate Response to cumulative Emissions (TCRE) is the cornerstone of estimates of carbon emissions budgets to future warming targets, characterizing the near-linear relationship between the increase in global mean temperature and cumulative emissions of CO2. TCRE is derived from highly sophisticated Earth System Models (ESMs) - some, however, lack important processes known to have a large impact on TCRE. Here, we use multiple configurations of UKESM, a full-complexity ESM, to estimate how TCRE of 11 ESMs that participated in Coupled Model Intercomparison Project 6 would change if each included six terrestrial carbon cycle related processes present in UKESM, such as nitrogen limitation of photosynthesis and fire-vegetation interactions. We find that accounting for processes not included in the models increases their TCRE by an average of 21.4% implying a reduction of 16.0% ± 0.8% in the carbon budget for the transition from 1.5°C to 2°C. Earth and environmental sciences/Climate sciences/Climate change Earth and environmental sciences/Biogeochemistry/Carbon cycle Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformationPaper3vn14.pdf Supplementary Information for Emulating absent land processes reduces carbon budgets in CMIP6 models 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-9203584","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":615579438,"identity":"4e183dd9-3e7a-4471-8712-b73d707fa860","order_by":0,"name":"Spencer 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