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dc.contributor.authorBeckerle, John C.  Concept link
dc.contributor.authorBaxter, Lincoln  Concept link
dc.contributor.authorPorter, Robert P.  Concept link
dc.contributor.authorSpindel, Robert C.  Concept link
dc.date.accessioned2018-04-12T18:13:12Z
dc.date.available2018-04-12T18:13:12Z
dc.date.issued1981-04
dc.identifier.citationBeckerle, J. C., Baxter, L., Porter, R. P., & Spindel, R. C. (1981). Sound channel propagation through eddies southeast of the Gulf Stream. Woods Hole Oceanographic Institution. https://doi.org/10.1575/1912/10238
dc.identifier.urihttps://hdl.handle.net/1912/10238
dc.descriptionAlso published as: Journal of the Acoustical Society of America 68 (1980): 1750-1767en_US
dc.description.abstractAcoustical signals at 270 Hz from SOFAR floats drifting in the region southeast of the Gulf Stream were recorded during most of 1975 from a near axis sound channel hydrophone near Bermuda. The amplitude levels received exhibit a large increase (12–18 dB) commencing about 24 July, following a long period (March to July) of relatively lower peak level amplitudes. A major part of the increase can be attributed to the influence of a large cyclonic eddy (Gulf Stream ring) that passed slowly between the SOFAR floats and Bermuda. Such an eddy produces a large sound speed anomaly that extends to depths below the axis of the sound channel. On 24 July, two SOFAR floats were known to have approximately the same sound transmission path through the edge of the large eddy. The sound transmission peaks occur when no ocean eddy is between the SOFAR floats and the receiver. Their spacing shows they occur at regular refraction caustics in the sound channel. When the sound transmission path passes through an eddy, these transmission focal distances are shifted to greater range and the signal level may be greatly enhanced. The decrease of caustic peak intensities with range is 5 dB per double distance, and this agrees with theory. Several different levels of peak acoustic intensity occur and these result from two float depths and oceanic thermocline oscillations.en_US
dc.description.sponsorshipPrepared for the Office of Naval Research under Contract N00014-74-C-0262; NR 083-004·.en_US
dc.language.isoen_USen_US
dc.publisherWoods Hole Oceanographic Institutionen_US
dc.relation.ispartofseriesWHOI Technical Reportsen_US
dc.relation.ispartofseriesWHOI-81-18en_US
dc.subjectUnderwater acousticsen_US
dc.subjectEddiesen_US
dc.titleSound channel propagation through eddies southeast of the Gulf Streamen_US
dc.typeTechnical Reporten_US
dc.identifier.doi10.1575/1912/10238


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