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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Topics in longshore currents

Church, John Casey. January 1993 (has links)
Thesis (Ph. D.)--Naval Postgraduate School, 1993. / Includes abstract. Includes bibliographical references.
72

Tropical instability waves in the Pacific Ocean

Masina, Simona, January 1996 (has links)
Thesis (Ph. D.)--Princeton University, 1996. / Includes bibliographical references (leaves 233-242).
73

A comparison of cross-stream velocities and Gulf Stream translations utilizing in-situ and remotely-sense data

Freise, Carl Bruce. January 1988 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, 1988. / "October 1988." "Funding was provided by the Office of Naval Research through contract Numbers N00014-86-K-0751 and N00014-87-K-0007, and by the United States Navy." Includes bibliographical references (leaves 46-48).
74

Drifter modeling and error assessment in wind driven currents

Furnans, Jordan Ernest. January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2005. / Vita. Includes bibliographical references.
75

Time-averaged model for longshore current and sediment transport in the surf and swash zones

Agarwal, Arpit . January 2005 (has links)
Thesis (M.S.)--University of Delaware, 2005. / Principal faculty advisor: Nobuhisa Kobayashi, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
76

The thermocline and current structure in subtropical/subpolar basins /

Huang, Rui Xin. January 1900 (has links)
Thesis (Ph. D.)--Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1984. / Bibliography: p. 215-218.
77

Dynamics of western boundary currents in simple models of low-latitude circulations /

Springer, Scott R. January 1994 (has links)
Thesis (Ph. D.)--University of Washington, 1994. / Vita. Includes bibliographical references (leaves [135]-144).
78

Lagrangian field observations of rip currents

Brown, Jeffrey W. January 2008 (has links)
Thesis (M.C.E.)--University of Delaware, 2008. / Principal faculty advisors: Jamie H. MacMahan and James T. Kirby, Dept. of Civil & Environmental Engineering. Includes bibliographical references.
79

Theoretical studies of the circulation of the Subarctic Pacific Region and the generation of Kelvin type waves by atmospheric distrubances

Thomson, Richard Edward January 1971 (has links)
Theoretical studies of two problems concerned with the surface forced, large-scale motions in bounded oceanic regions are presented. In Part I, such motions are considered for a particular area of the North Pacific Ocean known as the Subarctic Pacific Region. Discussion is based on the assumption that the velocity components may be separated into a time-averaged or quasi-steady flow about which fluctuations occur in the form of transient planetary waves. Some of the characteristics of the latter are briefly outlined. Several aspects of the time-averaged motions are then considered. A simple circulation, driven by the vertical velocity structure, is presented for the interior region of the ocean below the upper frictional layer. Also, using observational data to obtain the depth of the layer between the suface [sic] and the main halocline, this upper layer is found to behave as a geostrophic layer of fluid when averaged over many years. Combination of the above observed depths with the mean calculated Ekman divergences permitted calculation of a mean eddy coefficient of diffusivity for density. The results agree very well with those obtained by Veronis for similar oceanic situations. An explanation for the variations in the intrusion of 'warm' water along the top and bottom of the halocline off the coast of British Columbia is also given. The two final sections of Part I deal with the overall, quasi-steady circulation of the Subarctic Pacific Region. Here, a theoretical study is combined with the mean-monthly values of the calculated surface forcing. Curvilinear coordinates are used in order to model the northern boundary formed by the Aleutian-Komandorski island chain. The interior quasi-steady flow, which satisfies a Sverdrup-type balance of vorticity, is closed to the north by a frictional boundary layer. Using mean-monthly values for the surface winds over the region, the observed separation of the eastward flowing West Wind Drift into a northern and southern tending flow is found to correspond to the zero of the mean wind-stress curl. In the northern boundary layer, the characteristics of the westward flowing boundary current there, are shown to change downstream from a Western' to a 'zonal', type boundary current. The stability of the latter is dependent upon vorticity of appropriate sign being added to the boundary layer flow to balance that generated by friction along the coast. Discussion is also given for the effect of passes between the Aleutian islands on the zonal boundary current. Through a type of boundary layer 'suction' or, alternately, by mass transport into the boundary layer, the effect of these passes would seem to be to keep the boundary flow attached to the coast. Finally, spectral analysis of the wind-stress curl data, obtained from the mean-monthly surface pressure, is performed to determine its frequency distribution. A demodulation technique is used to determine the time variations of six of the frequency bands obtained in the spectral analysis. These results are then applied to the circulation in the Subarctic Pacific Region in an attempt to relate variations and spatial distribution in the circulation with the applied winds. The generation by the atmosphere of a type of long, boundary waves, known as Kelvin waves, is considered in Part II. In particular, it is shown that for a general large-scale distribution of wind and pressure systems that only the longshore component of the wind-stress and pressure can generate such waves. Examples are presented for a semi-infinite wind and moving pressure pattern. Kelvin waves are shown to move away from the force discontinuities at the speed of shallow-water waves. These waves are further found to exhibit a frequency shift, typical of non-dispersive waves from a moving source. Using some observed parameters for the atmospheric forcing terms off the Oregon coast of the United States, numerical values for the wave amplitudes for both examples are given. Part II has been published in the form presented here. Reference: J. Fluid Mech. C1970), 42C4), 657-670. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
80

Subsurface currents in the Strait of Georgia, west of Sturgeon Bank

Chang, Phillip Yit Kuen January 1976 (has links)
Spectral characteristics of sub-surface current and temperature records spanning 310-533 days from me Strait of Georgia near Sturgeon Bank are examined. Of particular interest are low-frequency fluctuations having, a characteristic period of 30 days. Typically, the energy of the low-frequency and tidal currents are equal at 50m (each about 40% of the total), and 10% and 10%, respectively, at 200m. Low-frequency currents are observed to be baroclinic and posses a lateral length scale less than 10km. Their generation mechanisms are not identified. The low-frequency fluctuations in sea-level and current have poor-to-fair coherence, while those in air-pressure and current have poor coherence. Low-frequency fluctuations in wind and current have fair coherence at the eastern mooring, and poor coherence at the remaining two moorings. Fluctuations in water temperature have a characteristic period of 300 days. Water temperatures at different locations generally have poor coherence except at the lowest frequencies where they are fair-to-good. Water temperature and current at the same location have poor coherence. Tidal currents are found to be ellipses, with the largest constituents being M² and K¹. The magnitude, shape .and orientation of the tidal current ellipses are time-dependent. Internal tides are suggested as an explanation. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

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