Three related problems concerning the response of the continental shelf waters to large-scale, low-frequency (synoptic scale) wind forcing are addressed. Briefly the results are as follows. (i) An understanding is gained to the dynamics of the poorly studied frictional region which lies inshore of the region which has been shown (e.g., Gill and Schumann, 1974 and Clarke and Van Gorder, 1984) to be well described by long wave dynamics. Simple accurate solutions for the pressure and alongshore velocity fields are developed and their domains of applicability are given. (ii) Through use of the knowledge gained in (i), a link is established from the frictional nearshore regions to the wave dynamics region by providing a proper boundary condition for models which strictly consider the latter. Also, a formula is given to predict coastal pressure (generally the best data set) given the boundary pressure prediction from a wave dynamics model. (iii) The above results, together with the model of Clarke and Van Gorder (1984), are applied to a data set on the West Florida Shelf. It is shown that the response there is accurately modeled. Further, the simplicity of the model allows the West Florida Shelf response to be understood as a sum of a forced wave moving with the wind field, a free wave generated at the Florida Keys and a smaller, but significant, free wave flux from the east coast of Florida. / Source: Dissertation Abstracts International, Volume: 46-01, Section: B, page: 0101. / Thesis (Ph.D.)--The Florida State University, 1984.

The separation between the surface and subsurface fronts of the Gulf Stream can change due to (a) changes in the curvature of the subsurface front as the Stream meanders, (b) wind-driven Ekman advection of the surface front, and (c) ageostrophic instabilities of the surface front. Combining observational field experiments, and theoretical and numerical modeling efforts, we showed that wind-driven Ekman advection of the Stream's surface front is not responsible for most of the observed variability in the Stream's surface-subsurface frontal separation. Our field experiments verified earlier ones when they demonstrated that part of the variability in the Stream's surface-subsurface separation is due to changes in the path of the Stream's surface front. To explain the observations an analytical expression was obtained which relates changes in separation to path curvature and shows that the strength of the curvature effect is proportional to the frontal separation at path inflection points. It was concluded that the majority in the variability in the frontal separation is due to instabilities of the surface front. / Source: Dissertation Abstracts International, Volume: 47-07, Section: B, page: 2817. / Thesis (Ph.D.)--The Florida State University, 1986.

Source: Dissertation Abstracts International, Volume: 32-09, Section: B, page: 5353. / Thesis (Ph.D.)--The Florida State University, 1971.

Source: Dissertation Abstracts International, Volume: 31-11, Section: B, page: 6788. / Thesis (Ph.D.)--The Florida State University, 1970.

This study is aimed at the modelling of mesoscale processes such as up/downwelling and ice edge eddies in the marginal ice zones. A 2-dimensional coupled ice-ocean model is used for the study. The ice model is coupled to the reduced gravity ocean model (f-plane) through interfacial stresses. The constitutive equations of the sea ice are formulated on the basis of the Reiner-Rivlin theory. The internal ice stresses are important only at high ice concentrations (90-100%), otherwise the ice motion is essentially free drift, where the air-ice stress is balanced by the ice-water stress. / The model was tested by studying the upwelling dynamics. Winds parallel to the ice edge with the ice on the right produce upwelling because the air-ice momentum flux is much greater than air-ocean momentum flux, and thus the Ekman transport is bigger under the ice than in the open water. / The upwelling simulation was extended to include temporally varying forcing, which was chosen to vary sinusoidally with 4 day period. This forcing resembles successive cyclone passings. In the model with thin oceanic upper layer, ice bands were formed. The up/downwelling signals do not disappear in wind reversals because of nonlinear advection. This leads to convergences and divergences in oceanic and ice velocities which manifest themselves as ice banding. At least one wind reversal is needed to produce one ice band. / A constant wind field exerted on a varying ice cover will generate vorticity leading to enhanced up/downwelling regions, i.e., wind forced vortices. Steepening and strengthening of the vortices are provided by the nonlinear terms. As in the case of ice band formation, the wind reversals will separate the vortices from the ice edge, so that the upwelling enhancements are pushed to the open ocean and the downwelling enhancements underneath the ice. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3454. / Thesis (Ph.D.)--The Florida State University, 1984.

Cyclonic ring interaction with the Gulf Stream recirculation is studied numerically using a two-layer quasigeostrophic model. Rings shed by the Gulf Stream in previous eddy-resolving general circulation experiments of Holland move westward, embedded in the recirculation. We find that these rings, when transferred to quiescent surroundings, have a nearly steady northward translation component, suggesting steering by the recirculation. Quasi-Lagrangian vorticity balances show that, if an isolated ring decays by Rossby wave dispersion, northward translation is required for potential vorticity conservation. / Although stable westward channel flows comparable to the recirculation failed to inhibit northward translation, a current that appeared to be barotropically unstable substantially reduced it. Energy extraction probably offset decay, reducing the need for planetary vorticity addition. / The trajectories in the general circulation model comprise two phases. Southward translation, after apparent separation, occurs in a region found baroclinically unstable by previous investigators. The ring continues to grow in area and relative vorticity. Decay characterizes the later phase. / The channel rings adjusted after a month to a quasi-steady deep potential vorticity configuration. A wedge of fluid intrudes the region below the ring from the south. The exiting fluid overshoots its undisturbed latitude, leaving a well-mixed wake. A somewhat weaker "deep eddy wedge" appears in general circulation experiments. / We find that moderate bottom slope can alter the deep potential vorticity distribution, preventing wedge formation. Deep potential vorticity influence on upper eddy dynamics may be critically related to potential vorticity homogenization and the structure of the thermocline. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3454. / Thesis (Ph.D.)--The Florida State University, 1984.

Two versions of an x-y-t, two-layer, numerical model with realistic coastline and bottom topography on a rotated (beta)-plane are used to study the upwelling system off the Peruvian coast. A hydrodynamic version of the model with two homogeneous layers is used to examine the interaction between the bottom topography and coastal trapped waves. / The fluctuations in the undercurrent off the Peruvian coast have been shown (Smith, 1978) to be uncorrelated with the local winds. The hypothesis proposed by Smith is that these fluctuations are the result of coastal trapped Kelvin waves. A parameterization scheme, based on Kelvin wave dynamics is introduced to simulate these coastal trapped waves. The relationship between bottom topographic features and the pycnocline height anomalies for a longshore current event is then examined. The principle of conservation of potential vorticity is used to explain the interactions between the waves and the bottom topography. The results of the hydrodynamic model shows that the interaction between a propagating waves and the bottom topography can play a significant role in determining the location of the centers of enhanced upwelling. / A thermodynamic version of the model, one in which the layer averaged densities are predicted variables, it used to extend the information available from the hydrodynamic models. A parameterization scheme for the interfacial mixing is introduced. There is a twofold reason for introducing thermodynamic and mixing into the model. The first is to include physics normally neglected in upwelling models. The second is to provide a physical mechanism to keep the interface from surfacing. The locations of the centers of enhanced upwelling as indicated by the interface displacement and sea surface temperature are examined and compared to observed data. The results of the thermodynamic model show that a positive heat flux is required to balance the large scale wind induced upwelling in order to observe the centers of enhanced upwelling due to internal waves/bottom topography interaction. / The local wind forcing for both versions of the model are derived from meteorological buoy wind observations. The time series of wind observations from Pacific Marine Environmental Laboratory's (PMEL) PSS-mooring during March, April, May (MAM) 1977 are used to construct the time-dependent amplitudes for the wind function. / Source: Dissertation Abstracts International, Volume: 42-01, Section: B, page: 0121. / Thesis (Ph.D.)--The Florida State University, 1980.

Source: Dissertation Abstracts International, Volume: 40-09, Section: B, page: 4181. / Thesis (Ph.D.)--The Florida State University, 1979.

Theoretical studies and numerical experiments of the subarctic front are conducted. The theoretical side of this research encompasses the determination of a stability criterion and the role friction plays as a dissipative mechanism. In the first case study, it is established that if the difference between the phase speed of the perturbation and the mean long-front geostrophic flow is greater than a certain value, the subarctic front is stable everywhere. In the other case study, it is proved that the time scale of dissipation is sufficiently large to neglect horizontal friction. While the effect of the westerly winds causes a southward shift of the front, the effect of a negative curl shows convergence at the front. This convergence strongly favors frontogenesis. / It is established that the phase speed of the first baroclinic mode is larger in a numerical model where a constant density jump between layers is employed. Thus, a smaller time scale is required to avoid the numerical instability caused by the violation of the CFL criterion. A numerical four-layer hydrodynamical model is implemented to investigate the role the atmosphere exerts on the dynamics of the subarctic front. / The salient features at the wake of a strong cyclone can be summarized as follows: (i) upwelling of 20 meters of the four interfaces occurs; (ii) the water remains upwelled for several weeks; (iii) the e-folding time scale of the vertical oscillations induced by the storm's passage is of the order of 10 days; (iv) a region of relative maximum convergence is observed in the lower layers below a region of relative maximum upwelling in the upper layer; and (v) the long and cross-front velocity fields are in quadrature in time, with the cross front velocity lagging the long front velocity. / With the exception of the cyclone's case, it is established that the effects of the atmospheric wind forcing are confined to the upper layer. These results are supported by oceanic observations. Finally, it is also proved that the response of the front to the atmospheric momentum transfer is independent of the initial form of the subarctic front. / Source: Dissertation Abstracts International, Volume: 42-01, Section: B, page: 0121. / Thesis (Ph.D.)--The Florida State University, 1981.

Source: Dissertation Abstracts International, Volume: 41-09, Section: B, page: 3368. / Thesis (Ph.D.)--The Florida State University, 1980.