{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T07:03:06Z","timestamp":1772262186961,"version":"3.50.1"},"reference-count":37,"publisher":"Copernicus GmbH","issue":"6","license":[{"start":{"date-parts":[[2023,11,29]],"date-time":"2023-11-29T00:00:00Z","timestamp":1701216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norges Forskningsr\u00e5d","doi-asserted-by":"publisher","award":["308796"],"award-info":[{"award-number":["308796"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Ocean Sci."],"abstract":"<jats:p>Abstract. We investigate data from an acoustic Doppler current profiler deployed in a constricted ocean channel showing a tidally dominated flow with intermittent velocity extrema during outflow from the constriction but not during inflow. A 2D numerical ocean model forced by tides is used to examine the spatial flow structure and underlying dynamical processes. We find that flow-separation eddies generated near the tightest constriction point form a dipole pair which propagates downstream and drives the observed intermittent flow variability. The eddies, which are generated by an along-channel adverse pressure gradient, spin up for some time near the constriction until they develop local low pressures in their centers that are strong enough to modify the background along-channel pressure gradient significantly. When the dipole has propagated some distance away from the constriction, the conditions for flow separation are recovered, and new eddies are formed.<\/jats:p>","DOI":"10.5194\/os-19-1633-2023","type":"journal-article","created":{"date-parts":[[2023,11,29]],"date-time":"2023-11-29T01:49:33Z","timestamp":1701222573000},"page":"1633-1648","source":"Crossref","is-referenced-by-count":0,"title":["Observations and modeling of tidally generated high-frequency velocity fluctuations downstream of a channel constriction"],"prefix":"10.5194","volume":"19","author":[{"given":"H\u00e5vard","family":"Espenes","sequence":"first","affiliation":[]},{"given":"P\u00e5l Erik","family":"Isachsen","sequence":"additional","affiliation":[]},{"given":"Ole Anders","family":"N\u00f8st","sequence":"additional","affiliation":[]}],"member":"3145","published-online":{"date-parts":[[2023,11,29]]},"reference":[{"key":"ref1","doi-asserted-by":"crossref","unstructured":"Afanasyev, Y.: Formation of vortex dipoles, Physics of fluids, 18, 037103, https:\/\/doi.org\/10.1063\/1.2182006, 2006.\u2002a, b, c","DOI":"10.1063\/1.2182006"},{"key":"ref2","doi-asserted-by":"crossref","unstructured":"Albagnac, J., Moulin, F.\u00a0Y., Eiff, O., Lacaze, L., and Brancher, P.: A three-dimensional experimental investigation of the structure of the spanwise vortex generated by a shallow vortex dipole, Environ. 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