Zero Emissions Commitment depends on warming level

Zero Emissions Commitment depends on warming level | 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 Zero Emissions Commitment depends on warming level Laura Gibbs, Chris Jones, Colin Jones, Timothy Andrews, Spencer Liddicoat, and 10 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8346352/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 When anthropogenic CO2 emissions cease, global temperature does not stabilise immediately. The resulting global temperature change, the Zero Emissions Commitment (ZEC), is central to carbon budget assessments and understanding reversibility of global warming, yet its dependence on prior warming levels remains unclear. Here we show, using zero-emission simulations with the UK Earth System Model (UKESM1.2) across global warming levels of 1.5–6K, that ZEC stays near-zero up to 2K, but becomes positive at higher warming levels, reaching 0.2–0.6K after ~150 years. This dependence indicates that stabilising or reversing warming becomes progressively more difficult as peak temperature rises. We identify the mechanism behind this behaviour: stronger warming from higher radiative disequilibrium and weakening carbon sinks, driven by saturated land carbon uptake and the reduced radiative impact of further CO2 drawdown. Higher peak warming therefore commits the planet to additional warming, limiting temperature-overshoot reversibility. Earth and environmental sciences/Climate sciences/Climate change/Projection and prediction Earth and environmental sciences/Climate sciences/Climate change/Climate and Earth system modelling Zero Emissions Commitment climate stabilisation carbon budgets ocean heat uptake carbon sinks earth system model Full Text Additional Declarations There is NO Competing Interest. Supplementary Files GibbsetalZECsuppmaterial.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. 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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-8346352","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":569364890,"identity":"312cb1d5-1627-4881-a03b-2bf734acdee4","order_by":0,"name":"Laura 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