Characterising Surface Discrepancies and Vertical Coherence of Ocean Temperature Anomalies in CMIP6 HighResMIP During ENSO Events

Characterising Surface Discrepancies and Vertical Coherence of Ocean Temperature Anomalies in CMIP6 HighResMIP During ENSO Events | 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 Research Article Characterising Surface Discrepancies and Vertical Coherence of Ocean Temperature Anomalies in CMIP6 HighResMIP During ENSO Events Sreevathsa Golla, Joël J.-M. Hirschi, Adam T. Blaker, Jennifer V. Mecking, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8345018/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 Considering the widespread implications of El Ni\ no–Southern Oscillation (ENSO) on global and regional climate through atmospheric and oceanic teleconnections, understanding its changing inter-annual dynamics in a warming climate is crucial. Evaluating the ability of high-resolution climate models to simulate the spatio-temporal characteristics and underlying dynamics of ENSO is essential for improving future projections. In this study, we review and evaluate ENSO representation in several high-resolution coupled climate model simulations from the CMIP6 HighResMIP project, along with two atmosphere-forced ocean-only simulations, focusing on the ability of climate models to represent central equatorial Pacific warming and cooling. We assess the spatio-temporal characteristics of surface and subsurface temperature anomalies in the equatorial Pacific Ocean that define ENSO events and compare model outputs with observations. We find good agreement in the timing, vertical structure, and coherence of surface and subsurface temperature anomalies between the forced-ocean simulations and observations, particularly in strong ENSO years. On the contrary, the coupled models project weaker eastern Pacific anomalies and relatively stronger central-basin contributions; however, substantial inter-model diversity remains in both spatial patterns and intensity. Furthermore, we highlight key shortcomings and discuss potential hypotheses that may explain the observed model diversity in simulating ENSO-related spatio-temporal characteristics. El Ni no-Southern Oscillation CMIP6 HighResMIP Thermocline Temperature Anomalies Full Text Supplementary Files SupplementaryMaterial.pdf 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-8345018","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":566451511,"identity":"7120c9d0-e213-4a7b-811e-031795d589ad","order_by":0,"name":"Sreevathsa Golla","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3ElEQVRIie2RMQrCMBRAfwmkS8Q1oJgrpGT3LBWhnQodBQumCHHs2k28QY/QIrSL4NrREvAYYnDSJe3okDeFD+/zPgFwOP4S7/iAXbb6muAxBSkOt1aYx2TFl9RTaCMnK6y4SJFiHJ9PRaNTWDOgUWhVeD9IXZJlUt2uSJSwDSSNartCGykIxUlFt3hBAIVAY2kPKxu5IBzFrPwoh3EF7rlRQrO8/yhXo4yF9Z4SpG4Dc4sQhHeBIs/QHlZ0Ws9eGWOnfNBkt2dzP+L2MPqzkk/4SJjbwx0Oh8MB8AZ7ij6PEBx8RwAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0003-4084-9677","institution":"University of Southampton School of Ocean and Earth Science","correspondingAuthor":true,"prefix":"","firstName":"Sreevathsa","middleName":"","lastName":"Golla","suffix":""},{"id":566451512,"identity":"06490378-13db-42e6-a6d4-d4fc13d4da3e","order_by":1,"name":"Joël J.-M. 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