Observationally constrained climate sensitivity implies high climate tipping risk

Observationally constrained climate sensitivity implies high climate tipping risk | 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 Observationally constrained climate sensitivity implies high climate tipping risk Rike Mühlhaus, Norman Julius Steinert, Johan Rockström, Nico Wunderling This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9105405/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 Global warming increases the risk of crossing climate tipping points, critical thresholds beyond which large-scale, potentially irreversible Earth system changes can be triggered. A major source of uncertainty in temperature projections is Equilibrium Climate Sensitivity (ECS). ECS measures long-term warming from a doubling of atmospheric CO2. We assess how ECS uncertainty affects tipping risk by feeding temperature projections from the climate emulator FaIR into PyCascades, which simulates interacting tipping elements. Higher ECS values strongly amplify the likelihood of crossing and triggering tipping points, showing a nonlinear, logistic relationship between ECS and tipping risk across a wide range of long-term CO2-stabilization levels. Under this relationship, recent observational constraints imply a long-term tipping risk of at least 82% under present-day CO2 concentration. In summary, overlooking the possibility of high climate sensitivity could lead to a disproportionate underestimation of tipping risks, necessitating a shift in how policymakers weigh the costs of continued carbon emissions. 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 TIPECSSupplementaries.pdf Supplementary information to the article Observationally constrained climate sensitivity implies high climate tipping risk 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-9105405","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":608305026,"identity":"bf1a2516-50f6-47d0-90ae-77cafaa8fe61","order_by":0,"name":"Rike 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