The Labrador Sea as a conduit of AMOC variability on multiple time scales

The Labrador Sea as a conduit of AMOC variability on multiple time scales | 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 The Labrador Sea as a conduit of AMOC variability on multiple time scales Jiajia chen, M. Susan Lozier This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6637014/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 Though the Atlantic Meridional Overturning Circulation (AMOC) is an essential element of the global climate system, the source of its variability on timescales longer than those observed remains unsettled. We conduct a broad study of that variability by examining transport on different timescales within the AMOC lower limb using climate simulations and OSNAP observations in the subpolar North Atlantic. We find that overturning in the Irminger and Iceland basins, rather than the Labrador Sea, predominantly drives subpolar AMOC variability from monthly to multidecadal scales. Due to the cyclonic circulation of the subpolar basin, the Labrador Sea essentially inherits variability via advection. Though water mass formation in the Labrador Sea can amplify that variability, the deep waters exiting this basin derive their signature from waters entering the basin. Coherent propagation of transport anomalies is a robust feature presented in OSNAP observations and the climate models studied herein. This study underscores the efficacy of using climate models in conjunction with observations to interrogate AMOC variability. Teaser : Though the Labrador Sea takes the last leg in the AMOC ‘relay’, the Irminger and Iceland basins have the largest downstream impact. Earth and environmental sciences/Ocean sciences/Physical oceanography Earth and environmental sciences/Climate sciences/Climate change/Climate and Earth system modelling Full Text Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.pdf Supplementary Information for The Labrador Sea as a conduit of AMOC variability on multiple time scales 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-6637014","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":469671140,"identity":"cfb1b613-bdd7-45ac-ba31-5e5d3945d340","order_by":0,"name":"Jiajia chen","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+ElEQVRIiWNgGAWjYBACxmYGBoMEBgYgYj4AFjEAYgkitbBBKIJaYAColseAOC3M7cwPCh7U2OXxS/d8fvHzh428OQPzwds8eB3GZmCQcCy5WHLO2W2WPQlphjsb2JKt8WthAGphO5C44UbuNgOehMMJBgd4zKTxa2H/YJDw70Di/hs5zwz/JPwHauH/RkALj4FBYhvQFokc5sc8CQdAtrAR0lJgkNiXnDjjRpoZs0xasuGGw2zGlnPwaDHsP77N8Mc3u8T+GcmPP76xsZM3ON788MYbfFoaGNgMoGw2SHQw41EOAvJAJQ+gbOYPBBSPglEwCkbBCAUAWzFPQEG/YxMAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-5438-0606","institution":"Georgia Institute of Technology","correspondingAuthor":true,"prefix":"","firstName":"Jiajia","middleName":"","lastName":"chen","suffix":""},{"id":469671141,"identity":"111e80ff-cacf-47a2-8f0b-d72acecd1e77","order_by":1,"name":"M. 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