Cross-scale phase relationship of the Ca II K index with solar wind parameters: a Space Climate focus

Cross-scale phase relationship of the Ca II K index with solar wind parameters: a Space Climate focus | 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 Cross-scale phase relationship of the Ca II K index with solar wind parameters: a Space Climate focus Raffaele Reda, Luca Giovannelli, Tommaso Alberti This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3826185/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Aug, 2024 Read the published version in Solar Physics → Version 1 posted 8 You are reading this latest preprint version Abstract The solar wind, representing one of the most impacting phenomena in the circum-terrestrial space, constitute one of the several manifestation of the magnetic activity of the Sun. With the aim of shedding light on the scales beyond the rotational period of the Sun (i.e., Space Climate scales), this study investigates the phase relationship of a solar activity physical proxy, the Ca II K index, with solar wind properties measured near the Earth, over the whole space era (last 5 solar cycles). By taking advantage of a powerful tool such as the Hilbert-Huang Transform, we investigate the dependence of their phase coherence on the obtained time scale components. Phase coherence at same time scales is found between all the components, while it is preserved also between adjacent components with time scales $\gtrsim$ 2 yrs. Finally, given the availability of the intrinsic modes of oscillation, we explore how the relationship of Ca II K index with solar wind parameters depends on the time scale considered. According to our results, we hypothesize the presence of a bifurcation in Ca II K index - solar wind speed (dynamic pressure) phase-space, where the time scale seems to act as bifurcation parameter. This concept may be pivotal for unraveling the complex interplay between solar activity and solar wind, bearing implications from the prediction and the interpretation point of view in Space Climate studies. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 02 Aug, 2024 Read the published version in Solar Physics → Version 1 posted Editorial decision: Revision requested 19 Jun, 2024 Reviews received at journal 18 Jun, 2024 Reviewers agreed at journal 30 May, 2024 Reviewers agreed at journal 04 Feb, 2024 Reviewers invited by journal 13 Jan, 2024 Editor assigned by journal 02 Jan, 2024 Submission checks completed at journal 02 Jan, 2024 First submitted to journal 31 Dec, 2023 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-3826185","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":264785981,"identity":"dd98f529-2c6d-46ed-a524-13c5ef65ba11","order_by":0,"name":"Raffaele Reda","email":"","orcid":"","institution":"University of Rome Tor Vergata","correspondingAuthor":false,"prefix":"","firstName":"Raffaele","middleName":"","lastName":"Reda","suffix":""},{"id":264785982,"identity":"58bf0f58-6f86-4482-868e-5ed07002738e","order_by":1,"name":"Luca Giovannelli","email":"data:image/png;base64,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","orcid":"","institution":"University of Rome Tor Vergata","correspondingAuthor":true,"prefix":"","firstName":"Luca","middleName":"","lastName":"Giovannelli","suffix":""},{"id":264785983,"identity":"a1065fe5-9f64-4546-8d63-389223a7557b","order_by":2,"name":"Tommaso Alberti","email":"","orcid":"","institution":"National Institute of Geophysics and Volcanology","correspondingAuthor":false,"prefix":"","firstName":"Tommaso","middleName":"","lastName":"Alberti","suffix":""}],"badges":[],"createdAt":"2023-12-31 16:14:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3826185/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3826185/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s11207-024-02346-3","type":"published","date":"2024-08-02T15:56:55+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":61793279,"identity":"376ffca9-30fb-4466-843a-4466d79b27dd","added_by":"auto","created_at":"2024-08-05 16:09:01","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2653623,"visible":true,"origin":"","legend":"","description":"","filename":"ArticoloSOLARNETPotsdam2023SolarPhysics.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3826185/v1_covered_68a8058b-fc56-4983-ae23-cf2a30b2a466.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Cross-scale phase relationship of the Ca II K index with solar wind parameters: a Space Climate focus","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"solar-physics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"sola","sideBox":"Learn more about [Solar Physics](http://link.springer.com/journal/11207)","snPcode":"11207","submissionUrl":"https://submission.nature.com/new-submission/11207/3","title":"Solar Physics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-3826185/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3826185/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"The solar wind, representing one of the most impacting phenomena in the circum-terrestrial space, constitute one of the several manifestation of the magnetic activity of the Sun. With the aim of shedding light on the scales beyond the rotational period of the Sun (i.e., Space Climate scales), this study investigates the phase relationship of a solar activity physical proxy, the Ca II K index, with solar wind properties measured near the Earth, over the whole space era (last 5 solar cycles). By taking advantage of a powerful tool such as the Hilbert-Huang Transform, we investigate the dependence of their phase coherence on the obtained time scale components. Phase coherence at same time scales is found between all the components, while it is preserved also between adjacent components with time scales $\\gtrsim$ 2 yrs. Finally, given the availability of the intrinsic modes of oscillation, we explore how the relationship of Ca II K index with solar wind parameters depends on the time scale considered. According to our results, we hypothesize the presence of a bifurcation in Ca II K index - solar wind speed (dynamic pressure) phase-space, where the time scale seems to act as bifurcation parameter. This concept may be pivotal for unraveling the complex interplay between solar activity and solar wind, bearing implications from the prediction and the interpretation point of view in Space Climate studies.","manuscriptTitle":"Cross-scale phase relationship of the Ca II K index with solar wind parameters: a Space Climate focus","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-04 15:36:42","doi":"10.21203/rs.3.rs-3826185/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-06-19T16:39:20+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-18T16:08:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"284315655077448186218750483701110311675","date":"2024-05-30T15:10:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"4cb29190-6ab2-42e4-aaf9-34477c6576b6","date":"2024-02-04T15:37:22+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-01-13T16:51:33+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-01-02T14:49:47+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-01-02T14:29:52+00:00","index":"","fulltext":""},{"type":"submitted","content":"Solar Physics","date":"2023-12-31T16:03:28+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"solar-physics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"sola","sideBox":"Learn more about [Solar Physics](http://link.springer.com/journal/11207)","snPcode":"11207","submissionUrl":"https://submission.nature.com/new-submission/11207/3","title":"Solar Physics","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"0d438af5-3b63-4cbe-8cb6-92dd6777c02d","owner":[],"postedDate":"January 4th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-08-05T15:59:09+00:00","versionOfRecord":{"articleIdentity":"rs-3826185","link":"https://doi.org/10.1007/s11207-024-02346-3","journal":{"identity":"solar-physics","isVorOnly":false,"title":"Solar Physics"},"publishedOn":"2024-08-02 15:56:55","publishedOnDateReadable":"August 2nd, 2024"},"versionCreatedAt":"2024-01-04 15:36:42","video":"","vorDoi":"10.1007/s11207-024-02346-3","vorDoiUrl":"https://doi.org/10.1007/s11207-024-02346-3","workflowStages":[]},"version":"v1","identity":"rs-3826185","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3826185","identity":"rs-3826185","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}