State dependence and an emergent constraint on warming after zero emissions

State dependence and an emergent constraint on warming after zero emissions | 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 State dependence and an emergent constraint on warming after zero emissions Sofia Palazzo Corner, Zebedee Nicholls, Chris Smith, Chris Jones, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7366911/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Global warming is expected to stabilise once carbon emissions are brought down to – and remain at – zero. Reaching net zero is thus an obligatory minimum to stay below a specific temperature threshold. But not all net zero futures are created equal. Here, we present an emergent constraint on the Zero Emissions Commitment (ZEC): the additional global temperature change in a world that reaches and sustains zero carbon emissions. We build a linear regression model on a handful of predictors derived from real-world observables that can be measured prior to net zero, and validate its performance on the behaviour of Earth System Models. Applying this constraint to present day observations, we find a best estimate of carbon-only ZEC 50 of 6% cooling [19% cooling to 7% warming] for a world that instantaneously achieves and sustains zero carbon emissions. This estimate shifts if climate action wavers. A warmer planet portends a world at higher risk of extra warming under zero emissions. Conversely, the more we restrain global warming on the way to zero carbon, the more likely we are to see temperatures fall without intervention. This win-win, lose-lose relationship fortifies the benefits of staying well within the limits of the Paris Agreement. Earth and environmental sciences/Climate sciences/Climate change/Climate and Earth system modelling Earth and environmental sciences/Climate sciences/Climate change/Projection and prediction Full Text Additional Declarations There is NO Competing Interest. Supplementary Files PalazzoCornerStateDependenceZECSI.docx Supplementary Information Cite Share Download PDF Status: Posted 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-7366911","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Physical Sciences - Article","associatedPublications":[],"authors":[{"id":509771589,"identity":"e93d3356-2504-4136-a500-a9b4476f6000","order_by":0,"name":"Sofia Palazzo Corner","email":"","orcid":"","institution":"Imperial College London","correspondingAuthor":false,"prefix":"","firstName":"Sofia","middleName":"Palazzo","lastName":"Corner","suffix":""},{"id":509771590,"identity":"a4ccf8d1-a1ec-4dfc-8cac-809cdf8b5400","order_by":1,"name":"Zebedee Nicholls","email":"","orcid":"","institution":"International Institute for Applied 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