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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.
31

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.
32

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).
33

The seasonal variation of the temperature and salinity of the surface waters of the British Columbia coast

McLeod, Donald Cameron January 1951 (has links)
For a number of years daily observations of surface temperature and salinity have been taken at ooeanographic stations (mostly lighthouses) on the B. C. coast. The present thesis is the first attempt that has been made to systematically analyse this data. The annual variation in temperature was seen to follow the general climatological trend of the B. C. coast at each of the stations, although a wide range in the amplitudes of these periodic variations was noted. The factors influencing the amplitude of the annual temperature curves were considered and such effects as incoming radiation, the extent of turbulence, the degree of shelter and the phenomena of upwelling due to horizontal wind stress (West Coast of Vancouver Island) have been discussed for each of the stations. Correlations were made between available meteorological information and the sea temperature observations and an attempt has been made to determine temperature contours of the B. C. coastal waters during the summer when the surface temperature is least uniform. The salinity observations were treated in an analogous manner to temperature and found to exhibit characteristic periodic annual variations. The stations were classified by means of these variations and the influences of precipitation and fresh water runoff, evaporation and mixing were discussed and correlations with meteorological observations were again made. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
34

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
35

Time variations of the Pacific equatorial undercurrent

Curran, Terrence Alexander January 1981 (has links)
Time variations of the Pacific equatorial undercurrent at 150° west longitude are described, based upon observations from the CSS Parizeau during January-February 1979. Typical velocity maxima were 80 cm s⁻¹ in the eastward direction and 60 cm s⁻¹ in the northward direction near the core depth at 150 metres. Associated standard errors were 15 cm s⁻¹ due to uncertainty in probe motion and 5 cm s⁻¹ due to inherent current meter noise. Scalar field analysis suggests that the mean zonal current flow in the equatorial undercurrent is modulated by Rossby waves with periods of 30 days. In the surface layer, waves with periods of approximately 17 days were detected. A detailed description of the current profiler used during the experiment is included in the Appendix. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
36

The impact of tropical Atlantic freshwater fluxes on the north Atlantic meridional overturning circulation

Spence, John Paul Gordon. 10 April 2008 (has links)
No description available.
37

Sea water temperature and salinity characteristics observed at Oregon Coast Stations in 1961

Denner, Warren Wilson 14 May 1963 (has links)
Graduation date: 1963
38

Ocean views : an investigation into human-ocean relations /

Kennedy, Deborah Jane. January 2007 (has links)
Thesis (Ph.D.)--Murdoch University, 2007. / Thesis submitted to the Faculty of Sustainability, Environmental and Life Sciences. Includes bibliographical references (p. [189]-205).
39

Impact of realistic mean flow on equatorial waves in the Pacific Ocean

Seidel, Howard Franklin. January 1999 (has links)
Thesis (Ph. D.)--Texas A & M University, 1999. / Vita. Includes bibliographical references (leaves 117-122).
40

Development, performance evaluation and application of a physical model of the Kenyan-Tanzanian coastal region /

Mayorga Adame, Claudia Gabriela. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 112-115). Also available on the World Wide Web.

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