Northern Hemisphere Jet Stream Waviness Has Been Governed by Natural Variability Since 1979

Northern Hemisphere Jet Stream Waviness Has Been Governed by Natural Variability Since 1979 | 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 Northern Hemisphere Jet Stream Waviness Has Been Governed by Natural Variability Since 1979 Mehmet Sedat Gözlet, Joakim Kjellsson, Mojib Latif This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6998502/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 As global climate change progresses, especially with the warming poles, the behaviour of the Northern Hemisphere jet-stream remains a key factor in predicting mid-latitude weather patterns. This study assesses whether the jet-stream has become wavier from 1979 to 2023 using daily 500 hPa geopotential height data. By analysing ERA5 reanalysis and state-of-the-art climate models, we isolate the effects of natural variability and CO2 forcing on jet-stream dynamics across four sub-regions of the Northern Hemisphere: Eurasia, North Atlantic, North America, and North Pacific. Contrary to some recent hypotheses, our findings reveal no significant increase in jet-stream waviness over the study period. While there are some seasonal variations, natural variability remains the primary driver of jet-stream behaviour, with limited influence from rising CO2 concentrations, particularly in spring and summer. These results contribute to ongoing discussions about the roles of natural variability and anthropogenic forcing in the past and/or future evolution of jet-stream dynamics. Earth and environmental sciences/Climate sciences/Atmospheric science/Atmospheric dynamics Earth and environmental sciences/Climate sciences/Climate change Full Text Additional Declarations There is NO Competing Interest. 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-6998502","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":480125039,"identity":"bb7a0127-7e0b-4d95-b807-5c6f4faa4e39","order_by":0,"name":"Mehmet Sedat Gözlet","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8UlEQVRIiWNgGAWjYHACxgNg6gAD4wMgxcNHjJ4DDAkgkpnZAKSFjRQtbBIgHkEt8u7tDw58/FEnx3f8/LHKrzl2MmwMzA8f3cCjxfDMgYSDMxIOG0ueSWa7LbstGegwNmPjHHxaZiQcOMyTcCBxwwGgFsltzEAtPGzS+LUkNhz+k1BXv+H8Y7ZiyW31hLXISyQzHGZIYE4wuJHMxvhx22HCWgx4jjEc7Ek7bDjzxmNjacZtx3nYmAn4Rb69/eGDHzZ18nznEx9+/Lmt2p6fvfnhY7y2HEDiMPOASTzKwbY0IHEYfxBQPQpGwSgYBSMTAADusE0R2zU3fgAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-8769-6204","institution":"GEOMAR Helmholtz Centre for Ocean Research Kiel","correspondingAuthor":true,"prefix":"","firstName":"Mehmet","middleName":"Sedat","lastName":"Gözlet","suffix":""},{"id":480125040,"identity":"aa936964-9e60-4973-84f7-6aa214a5a774","order_by":1,"name":"Joakim Kjellsson","email":"","orcid":"https://orcid.org/0000-0002-6405-5276","institution":"SMHI","correspondingAuthor":false,"prefix":"","firstName":"Joakim","middleName":"","lastName":"Kjellsson","suffix":""},{"id":480125041,"identity":"fc6f79b1-7850-4aab-a4ca-7002f3e85b1a","order_by":2,"name":"Mojib Latif","email":"","orcid":"https://orcid.org/0000-0003-1079-5604","institution":"GEOMAR Helmholtz Centre for Ocean Research Kiel","correspondingAuthor":false,"prefix":"","firstName":"Mojib","middleName":"","lastName":"Latif","suffix":""}],"badges":[],"createdAt":"2025-06-28 14:45:09","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6998502/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6998502/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":86329614,"identity":"25424ab1-3212-45bc-a5a7-147f8bc6ca60","added_by":"auto","created_at":"2025-07-09 11:49:02","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":20589302,"visible":true,"origin":"","legend":"Article File","description":"","filename":"NorthernHemisphereJetStreamWavinessHasBeenGovernedbyNaturalVariabilitySince1979byGozletKjellssonLatif.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6998502/v1_covered_72621ded-134a-4c20-ac98-dbe1039c6b6e.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Northern Hemisphere Jet Stream Waviness Has Been Governed by Natural Variability Since 1979","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"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":"","lastPublishedDoi":"10.21203/rs.3.rs-6998502/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6998502/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"As global climate change progresses, especially with the warming poles, the behaviour of the Northern Hemisphere jet-stream remains a key factor in predicting mid-latitude weather patterns. 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