{"@context":{"@vocab":"https://cir.nii.ac.jp/schema/1.0/","rdfs":"http://www.w3.org/2000/01/rdf-schema#","dc":"http://purl.org/dc/elements/1.1/","dcterms":"http://purl.org/dc/terms/","foaf":"http://xmlns.com/foaf/0.1/","prism":"http://prismstandard.org/namespaces/basic/2.0/","cinii":"http://ci.nii.ac.jp/ns/1.0/","datacite":"https://schema.datacite.org/meta/kernel-4/","ndl":"http://ndl.go.jp/dcndl/terms/","jpcoar":"https://github.com/JPCOAR/schema/blob/master/2.0/"},"@id":"https://cir.nii.ac.jp/crid/1360021389801897600.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"DOI","@value":"10.1029/2022ja030691"}},{"identifier":{"@type":"URI","@value":"https://onlinelibrary.wiley.com/doi/pdf/10.1029/2022JA030691"}},{"identifier":{"@type":"URI","@value":"https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2022JA030691"}},{"identifier":{"@type":"URI","@value":"https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2022JA030691"}}],"resourceType":"学術雑誌論文(journal article)","dc:title":[{"@value":"Using Principal Component Analysis of Satellite and Ground Magnetic Data to Model the Equatorial Electrojet and Derive Its Tidal Composition"}],"description":[{"type":"abstract","notation":[{"@value":"<jats:title>Abstract</jats:title><jats:p>The intensity of the equatorial electrojet (EEJ) shows temporal and spatial variability that is not yet fully understood nor accurately modeled. Atmospheric solar tides are among the main drivers of this variability but determining different tidal components and their respective time series is challenging. It requires good temporal and spatial coverage with observations, which, previously could only be achieved by accumulating data over many years. Here, we propose a new technique for modeling the EEJ based on principal component analysis (PCA) of a hybrid ground‐satellite geomagnetic data set. The proposed PCA‐based model (PCEEJ) represents the observed EEJ better than the climatological EEJM‐2 model, especially when there is good local time separation among the satellites involved. The amplitudes of various solar tidal modes are determined from PCEEJ based tidal equation fitting. This allows to evaluate interannual and intraannual changes of solar tidal signatures in the EEJ. On average, the obtained time series of migrating and nonmigrating tides agree with the average climatology available from earlier work. A comparison of tidal signatures in the EEJ with tides derived from neutral atmosphere temperature observations show a remarkable correlation for nonmigrating tides such as DE3, DE2, DE4, and SW4. The results indicate that it is possible to obtain a meaningful EEJ spectrum related to solar tides for a relatively short time interval of 70 days.</jats:p>"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1380021389801897605","@type":"Researcher","foaf:name":[{"@value":"Gabriel Soares"}],"jpcoar:affiliationName":[{"@value":"Observatório Nacional  Rio de Janeiro Brazil"},{"@value":"GFZ German Research Centre for Geosciences  Potsdam Germany"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897603","@type":"Researcher","foaf:name":[{"@value":"Yosuke Yamazaki"}],"jpcoar:affiliationName":[{"@value":"Leibniz Institute of Atmospheric Physics University of Rostock  Kühlungsborn Germany"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897604","@type":"Researcher","foaf:name":[{"@value":"Achim Morschhauser"}],"jpcoar:affiliationName":[{"@value":"GFZ German Research Centre for Geosciences  Potsdam Germany"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897602","@type":"Researcher","foaf:name":[{"@value":"Jürgen Matzka"}],"jpcoar:affiliationName":[{"@value":"GFZ German Research Centre for Geosciences  Potsdam Germany"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897608","@type":"Researcher","foaf:name":[{"@value":"Katia J. Pinheiro"}],"jpcoar:affiliationName":[{"@value":"Observatório Nacional  Rio de Janeiro Brazil"},{"@value":"GFZ German Research Centre for Geosciences  Potsdam Germany"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897606","@type":"Researcher","foaf:name":[{"@value":"Claudia Stolle"}],"jpcoar:affiliationName":[{"@value":"Leibniz Institute of Atmospheric Physics University of Rostock  Kühlungsborn Germany"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897600","@type":"Researcher","foaf:name":[{"@value":"Patrick Alken"}],"jpcoar:affiliationName":[{"@value":"Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder  Boulder CO USA"},{"@value":"National Centers for Environmental Information NOAA  Boulder CO USA"}]},{"@id":"https://cir.nii.ac.jp/crid/1420564276165969792","@type":"Researcher","personIdentifier":[{"@type":"KAKEN_RESEARCHERS","@value":"70284479"},{"@type":"NRID","@value":"1000070284479"},{"@type":"NRID","@value":"9000408820585"},{"@type":"NRID","@value":"9000408811798"},{"@type":"NRID","@value":"9000408813833"},{"@type":"NRID","@value":"9000002259847"},{"@type":"NRID","@value":"9000408809267"},{"@type":"NRID","@value":"9000408814544"},{"@type":"NRID","@value":"9000412525559"},{"@type":"NRID","@value":"9000408813640"},{"@type":"NRID","@value":"9000408813013"},{"@type":"NRID","@value":"9000254263498"},{"@type":"NRID","@value":"9000338691246"},{"@type":"NRID","@value":"9000331467260"},{"@type":"NRID","@value":"9000405633498"},{"@type":"NRID","@value":"9000002249933"},{"@type":"NRID","@value":"9000408857077"},{"@type":"NRID","@value":"9000332222021"},{"@type":"NRID","@value":"9000014232476"},{"@type":"NRID","@value":"9000408811418"},{"@type":"NRID","@value":"9000408820598"},{"@type":"NRID","@value":"9000398156146"},{"@type":"NRID","@value":"9000405633542"},{"@type":"NRID","@value":"9000254740187"},{"@type":"NRID","@value":"9000006621258"},{"@type":"NRID","@value":"9000000519639"},{"@type":"NRID","@value":"9000260198419"},{"@type":"NRID","@value":"9000254262064"},{"@type":"RESEARCHMAP","@value":"https://researchmap.jp/read0046231"}],"foaf:name":[{"@value":"Akimasa Yoshikawa"}],"jpcoar:affiliationName":[{"@value":"International Center for Space Weather Science and Education ICSWSE Kyushu University  Fukuoka Japan"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897607","@type":"Researcher","foaf:name":[{"@value":"Kornyanat Hozumi"}],"jpcoar:affiliationName":[{"@value":"Space Environment Laboratory National Institute of Information and Communications Technology  Koganei Japan"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897728","@type":"Researcher","foaf:name":[{"@value":"Atul Kulkarni"}],"jpcoar:affiliationName":[{"@value":"Indian Institute of Geomagnetism  Navi Mumbai India"}]},{"@id":"https://cir.nii.ac.jp/crid/1380021389801897729","@type":"Researcher","foaf:name":[{"@value":"Pornchai Supnithi"}],"jpcoar:affiliationName":[{"@value":"School of Engineering King Mongkut's Institute of Technology Ladkrabang  Bangkok Thailand"}]}],"publication":{"publicationIdentifier":[{"@type":"PISSN","@value":"21699380"},{"@type":"EISSN","@value":"21699402"}],"prism:publicationName":[{"@value":"Journal of Geophysical Research: Space Physics"}],"dc:publisher":[{"@value":"American Geophysical Union (AGU)"}],"prism:publicationDate":"2022-09","prism:volume":"127","prism:number":"9"},"reviewed":"false","dcterms:accessRights":"http://purl.org/coar/access_right/c_abf2","dc:rights":["http://creativecommons.org/licenses/by/4.0/"],"url":[{"@id":"https://onlinelibrary.wiley.com/doi/pdf/10.1029/2022JA030691"},{"@id":"https://onlinelibrary.wiley.com/doi/full-xml/10.1029/2022JA030691"},{"@id":"https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2022JA030691"}],"createdAt":"2022-09-20","modifiedAt":"2025-05-27","project":[{"@id":"https://cir.nii.ac.jp/crid/1040287907230717312","@type":"Project","projectIdentifier":[{"@type":"KAKEN","@value":"21H04518"},{"@type":"JGN","@value":"JP21H04518"},{"@type":"URI","@value":"https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-21H04518/"}],"notation":[{"@language":"ja","@value":"地上多点ネットワークに基づく超高層大気変動の緯度間結合の観測的研究"},{"@language":"en","@value":"Study of latitudinal coupling of upper atmospheric variations based on multi-point ground network observations"}]},{"@id":"https://cir.nii.ac.jp/crid/1040848250648732672","@type":"Project","projectIdentifier":[{"@type":"KAKEN","@value":"20H01961"},{"@type":"JGN","@value":"JP20H01961"},{"@type":"URI","@value":"https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20H01961/"}],"notation":[{"@language":"ja","@value":"磁気圏ダイナミクスを創発する磁気圏電離圏結合過程の探究"},{"@language":"en","@value":"Exploring the Magnetosphere-Ionosphere coupling process: emergence of magnetospheric dynamics"}]}],"relatedProduct":[{"@id":"https://cir.nii.ac.jp/crid/1360011145200036480","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Ground magnetic effects of the equatorial electrojet simulated by the TIE‐GCM driven by TIMED satellite data"}]},{"@id":"https://cir.nii.ac.jp/crid/1360013172677719168","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"SAC-C mission, an example of international 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winds"}]},{"@id":"https://cir.nii.ac.jp/crid/1360292620183950080","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"On tidal variability induced by nonlinear interaction with planetary waves"}]},{"@id":"https://cir.nii.ac.jp/crid/1360292620809775488","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"An application of principal component analysis to the interpretation of ionospheric current systems"}]},{"@id":"https://cir.nii.ac.jp/crid/1360574093742299904","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"CHAMP mission status"}]},{"@id":"https://cir.nii.ac.jp/crid/1360574094049510400","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"The equatorial electrojet as detected from the abnormal electric current distribution above Huancayo, Peru, and 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Activity"}]},{"@id":"https://cir.nii.ac.jp/crid/1360861294447025920","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"On the day‐to‐day variation of the equatorial electrojet during quiet periods"}]},{"@id":"https://cir.nii.ac.jp/crid/1360861714822321792","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Quantifying solar flux and geomagnetic main field influence on the equatorial ionospheric current system at the geomagnetic observatory Huancayo"}]},{"@id":"https://cir.nii.ac.jp/crid/1361137044946898176","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"An improved model equatorial electrojet with a meridional current system"}]},{"@id":"https://cir.nii.ac.jp/crid/1361137045214193408","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Resolution of direction of oceanic magnetic lineations by the sixth‐generation lithospheric magnetic field model from CHAMP satellite magnetic measurements"}]},{"@id":"https://cir.nii.ac.jp/crid/1361137046373552512","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Climatology of upward propagating diurnal and semidiurnal tides in the thermosphere"}]},{"@id":"https://cir.nii.ac.jp/crid/1361418518695851136","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Overview of the SABER experiment and preliminary calibration results"}]},{"@id":"https://cir.nii.ac.jp/crid/1361418519332285440","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Signature of the quiet-time magnetospheric magnetic field and its electromagnetic induction in the rotating Earth"}]},{"@id":"https://cir.nii.ac.jp/crid/1361418519711593088","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Equatorial electrojet at African longitudes: first results from magnetic measurements"}]},{"@id":"https://cir.nii.ac.jp/crid/1361418520551759744","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Swarm – An Earth Observation Mission investigating Geospace"}]},{"@id":"https://cir.nii.ac.jp/crid/1361418521502715264","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Sq and EEJ—A Review on the Daily Variation of the Geomagnetic Field Caused by Ionospheric Dynamo Currents"}]},{"@id":"https://cir.nii.ac.jp/crid/1361699994973146112","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Local time and longitude dependence of the equatorial electrojet magnetic effects"}]},{"@id":"https://cir.nii.ac.jp/crid/1361699996068119168","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Tidal variability in the ionospheric dynamo region"}]},{"@id":"https://cir.nii.ac.jp/crid/1361981469765750272","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Equatorial electrojet—I. Development of a model including winds and instabilities"}]},{"@id":"https://cir.nii.ac.jp/crid/1361981469896309376","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Ørsted satellite captures high‐precision geomagnetic field data"}]},{"@id":"https://cir.nii.ac.jp/crid/1361981469989428992","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Longitudinal and day‐to‐day variability in the ionosphere from lower atmosphere tidal forcing"}]},{"@id":"https://cir.nii.ac.jp/crid/1361981470204679168","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Noon‐time equatorial electrojet: Its spatial features as determined by the CHAMP satellite"}]},{"@id":"https://cir.nii.ac.jp/crid/1362262943394527616","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Longitudinal structure of the vertical <b>E</b> × <b>B</b> drift and ion density seen from ROCSAT‐1"}]},{"@id":"https://cir.nii.ac.jp/crid/1362262944402264192","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Variability and predictability of the space environment as related to lower atmosphere forcing"}]},{"@id":"https://cir.nii.ac.jp/crid/1362544420921886080","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"The influence of nonmigrating tides on the longitudinal variation of the equatorial electrojet"}]},{"@id":"https://cir.nii.ac.jp/crid/1362544421305927808","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Monthly tidal temperatures 20–120 km from TIMED/SABER"}]},{"@id":"https://cir.nii.ac.jp/crid/1362825895701613568","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Evidence for short spatial correlation lengths of the noontime equatorial electrojet inferred from a comparison of satellite and ground magnetic data"}]},{"@id":"https://cir.nii.ac.jp/crid/1363107368755092352","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Discrete Inverse Problems"}]},{"@id":"https://cir.nii.ac.jp/crid/1363388843605108480","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Longitudinal variation of the E‐region electric fields caused by atmospheric tides"}]},{"@id":"https://cir.nii.ac.jp/crid/1363388845776000384","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Changes in the Earth's magnetic field over the past century: Effects on the ionosphere‐thermosphere system and solar quiet (Sq) magnetic variation"}]},{"@id":"https://cir.nii.ac.jp/crid/1363670319045632000","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Equatorial electrojet and regular daily variation S—I. A determination of the equatorial electrojet parameters"}]},{"@id":"https://cir.nii.ac.jp/crid/1363670319447714304","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"The equatorial electrojet"}]},{"@id":"https://cir.nii.ac.jp/crid/1363670320445333120","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"The H and Z variations along and near the equatorial electrojet in India, Africa and the Pacific"}]},{"@id":"https://cir.nii.ac.jp/crid/1363951794008790656","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Spatio‐temporal characterization of the equatorial electrojet from CHAMP, Ørsted, and SAC‐C satellite magnetic measurements"}]},{"@id":"https://cir.nii.ac.jp/crid/1364233269664832896","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Excitation mechanism of non-migrating tides"}]},{"@id":"https://cir.nii.ac.jp/crid/1390282681485733120","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@language":"en","@value":"Variation of Sq Induced by Atmospheric Tides Simulated by a Middle Atmosphere General Circulation Model."},{"@language":"ja-Kana","@value":"Variation of Sq Induced by Atmospheric"}]},{"@id":"https://cir.nii.ac.jp/crid/1390282681485746432","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@language":"en","@value":"Characteristics of the Equatorial Electrojet determined from an array of magnetometers in N-NE Brazil"}]},{"@id":"https://cir.nii.ac.jp/crid/1390282681490216448","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@language":"en","@value":"<I>Swarm</I>: A constellation to study the Earth's magnetic field"},{"@value":"Swarm: A constellation to study the Earth's magnetic field"}]},{"@id":"https://cir.nii.ac.jp/crid/2050025942185038464","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Swarm SCARF equatorial electric field inversion chain"}]},{"@id":"https://cir.nii.ac.jp/crid/2051714792052378240","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Empirical model of equatorial electrojet based on ground-based magnetometer data during solar minimum in fall"}]},{"@id":"https://cir.nii.ac.jp/crid/2051996266840007680","@type":"Article","relationType":["references"],"jpcoar:relatedTitle":[{"@value":"Recent geomagnetic secular variation from Swarm and ground observatories as estimated in the CHAOS-6 geomagnetic field model"}]}],"dataSourceIdentifier":[{"@type":"CROSSREF","@value":"10.1029/2022ja030691"},{"@type":"KAKEN","@value":"PRODUCT-25119335"},{"@type":"KAKEN","@value":"PRODUCT-25133022"}]}