Influence of Subtropical Jets on the Equatorial Wave Spectrum: implications for future changes in Kelvin waves and MJO variance

Influence of Subtropical Jets on the Equatorial Wave Spectrum: implications for future changes in Kelvin waves and MJO variance | 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 Influence of Subtropical Jets on the Equatorial Wave Spectrum: implications for future changes in Kelvin waves and MJO variance Hagar Bartana, Chaim Garfinkel, Chen Schwartz, Ofer Shamir, Jian RAO This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4394120/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 Models from phase 6 of the Coupled Model Intercomparison Project (CMIP6), simulate an intensification in equatorial Kelvin Waves (KW) and the Madden-Julian Oscillation (MJO) with global warming. In contrast, the power spectrum is projected to weaken for most other wavenumber-frequency combinations, including higher wavenumber Equatorial Rossby waves (ER). The qualitatively different projected response of KW and ER suggest that dynamical forcings have an important role in the physical mechanism of the changes. This hypothesis is tested using targeted simulations of the Model of an Idealised Moist Atmosphere (MiMA) in which we impose perturbations in upper-tropospheric zonal winds that mimic projected end-of-century changes. These simulations demonstrate that future changes in KW and the MJO strongly depend on changes in the South Pacific subtropical jet. A similar dependence is also evident in CMIP6 models. These results have implications for future projections of KW and MJO activity in models with biased subtropical jets. Convectively coupled equatorial waves Kelvin waves Madden-Julian Oscillation Equatorial spectrum South Pacific subtropical jet Full Text 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-4394120","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":304968581,"identity":"601da5bc-cd72-4b73-bae3-98fbdc093f12","order_by":0,"name":"Hagar Bartana","email":"data:image/png;base64,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","orcid":"https://orcid.org/0000-0002-4278-4590","institution":"Hebrew University of Jerusalem Fredy and Nadine Herrmann Institute of Earth Sciences","correspondingAuthor":true,"prefix":"","firstName":"Hagar","middleName":"","lastName":"Bartana","suffix":""},{"id":304968582,"identity":"dc905399-29e0-4ea0-8b2f-ba0ed82b805f","order_by":1,"name":"Chaim Garfinkel","email":"","orcid":"","institution":"Hebrew University of Jerusalem","correspondingAuthor":false,"prefix":"","firstName":"Chaim","middleName":"","lastName":"Garfinkel","suffix":""},{"id":304968583,"identity":"493748e7-1da1-4356-bc82-84c51c4d6bfd","order_by":2,"name":"Chen Schwartz","email":"","orcid":"","institution":"Hebrew University of Jerusalem","correspondingAuthor":false,"prefix":"","firstName":"Chen","middleName":"","lastName":"Schwartz","suffix":""},{"id":304968584,"identity":"1e49a1df-e95e-4e90-993f-5b77534f5654","order_by":3,"name":"Ofer Shamir","email":"","orcid":"","institution":"New York University Courant Institute of Mathematical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Ofer","middleName":"","lastName":"Shamir","suffix":""},{"id":304968585,"identity":"15f3655f-2b78-4f86-b392-0cc30969d595","order_by":4,"name":"Jian RAO","email":"","orcid":"","institution":"Nanjing University of Information Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Jian","middleName":"","lastName":"RAO","suffix":""}],"badges":[],"createdAt":"2024-05-09 09:31:05","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4394120/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4394120/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":64556813,"identity":"c43e596d-8f16-4425-9032-00d100a65808","added_by":"auto","created_at":"2024-09-15 14:06:37","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4036748,"visible":true,"origin":"","legend":"","description":"","filename":"KW.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4394120/v1_covered_f14463cf-f0ae-4cb2-a1d6-01abd6828ca8.pdf"}],"financialInterests":"","formattedTitle":"Influence of Subtropical Jets on the Equatorial Wave Spectrum: implications for future changes in Kelvin waves and MJO variance","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Convectively coupled equatorial waves, Kelvin waves, Madden-Julian Oscillation, Equatorial spectrum, South Pacific subtropical jet","lastPublishedDoi":"10.21203/rs.3.rs-4394120/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4394120/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e Models from phase 6 of the Coupled Model Intercomparison Project (CMIP6), simulate an intensification in equatorial Kelvin Waves (KW) and the Madden-Julian Oscillation (MJO) with global warming. 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