What advances monsoon onset over India?

What advances monsoon onset over India? | 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 What advances monsoon onset over India? Bidyut Goswami, Caroline Muller This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3743877/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract In the monsoon regions, atmospheric convection is typically stronger over the oceans than over land. Rainfall over land is potentially affected by the dynamic response of the atmosphere to deep convection over the adjacent oceans. Here, we show, in the case of the Indian summer monsoon, that enhanced atmospheric deep convection over the Bay of Bengal ∼2 weeks before onset, advances monsoon onset over India. Since the sea surface temperature of the Bay of Bengal is already hot during spring, warm anomalies further enhance convection that drives a convergence of low-level winds. A part of this circulation response blows from central India to the Bay of Bengal. It paves the way for monsoon circulation over India and advances the onset of monsoon. We tested this hypothesis using an atmospheric model forcing it by warm sea surface temperature anomalies over the Bay of Bengal 10-15 days before monsoon onset. Earth and environmental sciences/Climate sciences/Atmospheric science/Atmospheric dynamics Earth and environmental sciences/Climate sciences/Atmospheric science Full Text Additional Declarations The authors declare no competing interests. Supplementary Files manuscriptsupplementary.pdf Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions 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. 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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-3743877","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":261128022,"identity":"6acc8b95-ca15-4425-8e8b-8d27154abb5d","order_by":0,"name":"Bidyut Goswami","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4ElEQVRIiWNgGAWjYBACAyjNw89MshbJZgbGBgibgGYDOOMAsVrM+Rcf/sxTs03G+Dj78wc/GOzkGdjPH8CrxXLGszRpnmO3ecwO8xg29jAkGzbwJBNw2I0zZsw5bGAtjA08DMwJDAyEtRh/zvl3m8e4mf1h4x+G+gQG/scEtJzvMZDObbvNY8DMYNjMw3A4gUGCgC2WM9jSpP/23eaRAPpltozBccM2iccGeLWY8x8+/HHGt9v2/P3HH3x8U1Etz8+f+AC/NRIJKO5kYGDDrx4I+A8QVDIKRsEoGAUjHQAAZjhAzxCf9A4AAAAASUVORK5CYII=","orcid":"","institution":"Institute of Science and Technology Austria","correspondingAuthor":true,"prefix":"","firstName":"Bidyut","middleName":"","lastName":"Goswami","suffix":""},{"id":261128023,"identity":"596f9317-eca8-4574-8223-b76310dfb0d1","order_by":1,"name":"Caroline Muller","email":"","orcid":"","institution":"Institute of Science and Technology Austria","correspondingAuthor":false,"prefix":"","firstName":"Caroline","middleName":"","lastName":"Muller","suffix":""}],"badges":[],"createdAt":"2023-12-12 12:45:25","currentVersionCode":2,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-3743877/v2","doiUrl":"https://doi.org/10.21203/rs.3.rs-3743877/v2","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":68303733,"identity":"1a251ba8-a7cd-42a5-bcbd-9d92eb4f94a6","added_by":"auto","created_at":"2024-11-05 22:16:23","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5754343,"visible":true,"origin":"","legend":"","description":"","filename":"MonsoonOnsetWCD.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3743877/v2_covered_7514e5da-6f85-43a3-9440-5999525be814.pdf"},{"id":68303353,"identity":"bd36ee89-d1e0-47ae-9aaf-b1b47263aedf","added_by":"auto","created_at":"2024-11-05 22:00:15","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":13116429,"visible":true,"origin":"","legend":"","description":"","filename":"manuscriptsupplementary.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3743877/v2/713a0d2633a7ee9ee102aece.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"What advances monsoon onset over India?","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":"","lastPublishedDoi":"10.21203/rs.3.rs-3743877/v2","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3743877/v2","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn the monsoon regions, atmospheric convection is typically stronger over the oceans than over land. 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