{"@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/1363951795703661440.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"DOI","@value":"10.1186/bf03352785"}},{"identifier":{"@type":"URI","@value":"https://link.springer.com/content/pdf/10.1186/BF03352785.pdf"}},{"identifier":{"@type":"URI","@value":"https://link.springer.com/article/10.1186/BF03352785/fulltext.html"}},{"identifier":{"@type":"URI","@value":"http://link.springer.com/content/pdf/10.1186/BF03352785"}}],"dc:title":[{"@value":"Temporal variation of sound speed in ocean: a comparison between GPS/acoustic and in situ measurements"}],"description":[{"type":"abstract","notation":[{"@value":"<jats:title>Abstract</jats:title>\n          <jats:p>The GPS/acoustic technique applied to seafloor geodesy intrinsically measures integrated sound speed along a trajectory of an acoustic signal as well as the position of a seafloor transponder array. We present here a generalized expression of sound speed variation in terms of a traveltime residual normalized to the vertical component. With this expression, residual traveltimes to any seafloor transponders will have a same value regardless of their depths and slant angles. This is valid even for the case having horizontal gradient in sound speed structure; the gradient affects only on positioning of a transponder array and not on the estimate of sound speed just beneath the observation point. We monitored temporal variation of this quantity through a GPS/acoustic survey and compared it with <jats:italic>in situ</jats:italic> expendable bathythermograph (XBT) measurements periodically carried out during the survey. We found that the relative change of the two independent measurements are in good agreement within 5% of the typical amplitude of temporal variation.</jats:p>"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1383951795703661442","@type":"Researcher","foaf:name":[{"@value":"Motoyuki Kido"}]},{"@id":"https://cir.nii.ac.jp/crid/1383951795703661441","@type":"Researcher","foaf:name":[{"@value":"Yukihito Osada"}]},{"@id":"https://cir.nii.ac.jp/crid/1383951795703661440","@type":"Researcher","foaf:name":[{"@value":"Hiromi Fujimoto"}]}],"publication":{"publicationIdentifier":[{"@type":"EISSN","@value":"18805981"}],"prism:publicationName":[{"@value":"Earth, Planets and Space"}],"dc:publisher":[{"@value":"Springer Science and Business Media LLC"}],"prism:publicationDate":"2008-03","prism:volume":"60","prism:number":"3","prism:startingPage":"229","prism:endingPage":"234"},"reviewed":"false","dcterms:accessRights":"http://purl.org/coar/access_right/c_abf2","dc:rights":["https://creativecommons.org/licenses/by/4.0/","https://creativecommons.org/licenses/by/4.0/"],"url":[{"@id":"https://link.springer.com/content/pdf/10.1186/BF03352785.pdf"},{"@id":"https://link.springer.com/article/10.1186/BF03352785/fulltext.html"},{"@id":"http://link.springer.com/content/pdf/10.1186/BF03352785"}],"createdAt":"2014-08-15","modifiedAt":"2021-09-02","relatedProduct":[{"@id":"https://cir.nii.ac.jp/crid/1360002216799083392","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@value":"Prevalence of viscoelastic relaxation after the 2011 Tohoku-oki earthquake"}]},{"@id":"https://cir.nii.ac.jp/crid/1360021391856158848","@type":"Article","resourceType":"学術雑誌論文(journal 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