Assessing Tropical Basin Interactions in SEAS5-20C. Impact on ENSO predictability

Assessing Tropical Basin Interactions in SEAS5-20C. Impact on ENSO predictability | 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 Assessing Tropical Basin Interactions in SEAS5-20C. Impact on ENSO predictability Antonio Jesús Robles Fernández, Belén Rodríguez-Fonseca, Teresa Losada Doval, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8425483/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 El Niño is the leading mode of interannual climate variability, driving seasonal predictability worldwide. It has been found that tropical variability, as that in the Atlantic, can impact on ENSO in certain decades, affecting its predictability. Nevertheless, a comprenhensive analysis of the role of the Tropical Atlantic in changing ENSO predictability along time has not been assessed so far. This work analyses the Atlantic-Pacific connection and its impact on ENSO prediction using the 20th century reforecast of the ECMWF operational seasonal forecast model, SEAS5-20C, for which changes in ENSO predictive skill over the century have been previously found. Using this reforecast, multidecadal variability of tropical basin interactions appear together with changes in tropical Atlantic and Pacific predictability. It is found how the connection between tropical basins is related to the improvement in ENSO prediction, even in the second year after the initialization (+12 month lead-time), confirming that changes in the background conditions modulates these changes in predictability. Earth and environmental sciences/Climate sciences Earth and environmental sciences/Ocean sciences ENSO Tropical Basin Interaction Atlantic Niño Seasonal prediction Full Text Additional Declarations No competing interests reported. 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-8425483","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":566291022,"identity":"40e57cbd-b887-479e-8482-fb05dc83a7f9","order_by":0,"name":"Antonio Jesús Robles Fernández","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAp0lEQVRIiWNgGAWjYBCDBH4SFDNDtEg2kKzF4ACxGvhn9x98XLjHJs/4RvLTDQwVdYS1SNw5zGw841lasdmNNLMbDGcOE2HNjWQ2aZ4DhxO33chhu8HYRoTz5GFaNs8AaflHhMMMYFo2SIC0NDAT1mJ4I9nYmOdAWrHEmWdmNxKOEeEXuRuJDx/zHLDJ429PfnbjQw0RDkMFCaRqGAWjYBSMglGAHQAAWfM6hTjpS+QAAAAASUVORK5CYII=","orcid":"","institution":"Complutense University of Madrid","correspondingAuthor":true,"prefix":"","firstName":"Antonio","middleName":"Jesús Robles","lastName":"Fernández","suffix":""},{"id":566291023,"identity":"271194ef-2e18-4cc2-8f39-b5b6cfc910db","order_by":1,"name":"Belén Rodríguez-Fonseca","email":"","orcid":"","institution":"Complutense University of Madrid","correspondingAuthor":false,"prefix":"","firstName":"Belén","middleName":"","lastName":"Rodríguez-Fonseca","suffix":""},{"id":566291024,"identity":"12d26349-015d-458a-ae1a-e11a649f0a1c","order_by":2,"name":"Teresa Losada Doval","email":"","orcid":"","institution":"Complutense University of Madrid","correspondingAuthor":false,"prefix":"","firstName":"Teresa","middleName":"Losada","lastName":"Doval","suffix":""},{"id":566291025,"identity":"a8dbca4e-4381-4d12-9fbd-0f41661beaee","order_by":3,"name":"Magdalena Alonso Balmaseda","email":"","orcid":"","institution":"European Centre for Medium-Range Weather Forecasts","correspondingAuthor":false,"prefix":"","firstName":"Magdalena","middleName":"Alonso","lastName":"Balmaseda","suffix":""}],"badges":[],"createdAt":"2025-12-22 14:08:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8425483/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8425483/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":99795540,"identity":"8b4012ce-091d-4dae-8028-fbe227508e57","added_by":"auto","created_at":"2026-01-08 13:38:31","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1554975,"visible":true,"origin":"","legend":"","description":"","filename":"RoblesetalmanuscriptTBISEAS5.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8425483/v1_covered_67b85897-b618-45f9-8297-c417f11b24f9.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Assessing Tropical Basin Interactions in SEAS5-20C. 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