McNeil, Craig Logan

Graduate

Birmingham, Ryan W

We use a numerical ocean model to evaluate the hypothesis that the continental shelves are significant sources of dissolved iron to the Southern Ocean. We simulate the distribution of passive tracers released from the 18 different continental shelf regions of the extra-tropical southern hemisphere oceans using an offline, eddy-permitting transport model. The circulation fields are taken from the Southern Ocean State Estimate, and we only simulate the transport of inert tracers focusing on the ph...

Whitney, Claudia S.

Approved for public release; distribution is unlimited / A primitive equation ocean general circulation model, with mixed layer physics, has been developed and applied to an investigation of the equatorial ocean. The major physical problem addressed with this model is the response of the upper ocean to westerly wind events, such as those that occur during tropical cyclones and during El Nino events. In the model development phase, several configurations of the mixed layer physics, domain ...

Gale, Allison

This study addresses the influences on ridge basalt chemistry, through analysis of their major and trace element and isotopic composition at scales ranging from individual ridge segments to the entire length of the ridge system. Local-scale studies of basalts along the Mid-Atlantic Ridge shed light on crustal accretion at slow-spreading ridges, and on the nature of plume-ridge interaction in this region. We show that segments must have multiple supplies of magma delivered along their length, but...

Pimentel, Fernando M. M.

Approved for public release; distribution is unlimited / In the thesis, the use of Wentzel-Kramers-Brillouin (WKB) Theory to obtain the solution to the Helmholtz Equation governing the acoustic normal modes is examined. Specifically, uniformly valid WKB solutions for four classes of acoustic normal modes in the ocean are derived and the accuracy of the WKB approximation is tested against some exact solutions. It is found that this inherently high frequency technique has an appreciable accuracy...

Smith, Amy R

Approved for public release; distribution is unlimited / This dissertation examines the effects of ocean mesoscale variability on acoustic arrival time patterns for two separate ocean environments. First, for an open ocean environment away from strong boundary currents, the effects of randomly phased linear baroclinic Rossby waves on acoustic travel time are shown to produce a variable overall spreading in the arrival pattern, primarily producing a delay in the later, axial arrivals. Second, usi...

Shaaban, Ahmed A.

<p> Tropical East Africa is influenced by two main rainy seasons, during autumn and spring. During autumn, tropical East African precipitation is clearly influenced by Indian Ocean Dipole (IOD) and/or ENSO. During spring, there is no clear SST pattern in the Indian Ocean. The association between El Ni&ntilde;o and positive IOD phases is much stronger than the association between La Ni&ntilde;a and negative IOD during October and November. During October, the association between El Ni&ntilde;o an...

Drake, Matthew C.

In the ocean, internal gravity waves are generated by tidal flow over sea floor topography. An internal gravity wave is only able to freely propagate if the buoyancy frequency is greater than the driving frequency, where the buoyancy frequency is proportional to the square root of the density gradient. A turning depth is defined as a height below which the buoyancy frequency is less than the driving frequency. King et al. showed that turning depths for internal waves generated by lunar tidal flo...

Pappas, Siobhan Bridget

Pertussis, also known as whooping cough, is a vaccine-preventable disease that is on the rise in the United States, a trend which has been attributed to vaccination exemption. Indeed, the pertussis outbreak that occurred in February, 2012 in Ocean County, New Jersey was associated with vaccine exemption. Considering that pertussis is deadly to young children, it is important to understand why this disease rate is on the rise. The research questions were focused on whether a relationship existed ...

Fine, Caitlin Marie

<p> A myriad of processes acting singly or in concert may contribute to tropical cyclogenesis, including convectively coupled waves, breakdown of the inter-tropical convergence zone (ITCZ), or upper-level troughs. This thesis investigates the role that topographic effects from the island of Sumatra may play in initiating tropical cyclogenesis (TC genesis) in the eastern Indian Ocean. If easterly flow is split by the mountains of Sumatra, counter-rotating lee vortices may form downstream. Because...

Hansen, William J.

No description available.

Su, Lin, 1966-

We have coupled a 3-dimensional physical planetary geostrophic ocean general circulation model to different biological models to investigate the interaction between physical and biological processes. A 1-dimensional particle cycle model with two particle size classes has been developed and coupled to the physical model as well. / The ocean model (Zhang et al., 1992) is based on the planetary geostrophic equations in spherical coordinates. The model equations include the full prognostic temperatu...

Simpson, Kyle G. F.

Inclement climate conditions have made the Arctic Ocean logistically difficult to study, and thus, our historical knowledge of Arctic Ocean processes are limited. Recent observations indicate rapid and abrupt changes in climate. These changes are thought to includes rising temperatures, increase storm activity, altered freshwater balance and a notable decrease in the concentration and extent of sea ice covering the Arctic Ocean. Increasing awareness of these changing conditions and our poor know...

Yang, Xiufeng

Ocean currents are an attractive source of clean energy due to their inherent reliability, persistence and sustainability. The Gulf Stream system is of particular interest as a potential energy resource to the United States with significant currents and proximity to the large population on the U.S. east coast. To assess the energy potential from ocean currents for the United States, the characterization of ocean currents along the U.S. coastline is performed in this dissertation. A GIS database ...

McKay, Jennifer Lynn

Marine sediment cores from the continental margin off Western Canada (48° to 50°N, 125 to 128°W) yield evidence of dramatic changes in oceanographic conditions over the last 16 kyr. During the late Glacial the accumulation of marine organic matter was greatly reduced. This reflects low primary and export production because glacial-mode atmospheric circulation did not drive coastal upwelling. At the start of the Boiling warm period (-14.3 kyr B.P.), and coincident with the retreat of glacier...

Downer, Joshua, n/a

A marginal ice zone (MIZ) is characterised by distinct ice floes and its direct exposure to the open ocean. Sea ice is typically described as a continuous material but this description can be inappropriate in an MIZ due to the granular nature of the ice cover and the scale of processes acting on the ice floes. In this thesis, the kinematic behaviour of sea ice in an MIZ modelled as a granular material is investigated with an emphasis on the influence of ocean waves. The kinematic behaviour of ...

Griffith, Gary P, n/a

When light intensities become supersaturating for photosynthesis, phytoplankton must be able to protect the photosynthetic machinery from potential damage by excess energy absorption. One of the most important photoprotective mechanisms involves the nonradiative dissipation of excess light energy by the interconversion of the carotenoid pigments of the so-called xanthophyll cycle. Very little is known about how the xanthophyll cycle of natural communities of phytoplankton responds to high light ...

Cirano, Mauro, School of Mathematics, UNSW

A numerical study is made of the wintertime circulation within the Southeast Indian Ocean (SEIO). The downwelling favourable winds result in a continuous eastward Coastal Current (CC) extending from Cape Leeuwin to the eastern coast of Tasmania, where it forms a confluence with the south branch of the East Australian Current. An additional forcing mechanism for the CC is the Leeuwin Current in the western part of the domain. The study here is divided in two parts: (1) available data and the win...

Zhuang, Haixiong, School of Mathematics, UNSW

Atmosphere-ocean and atmosphere-land interactions are important processes which determine the development of monsoon systems. In this study, a new atmosphere-ocean surface interaction scheme, referred to as AOSIS, is developed and verified with observed data. AOSIS, together with ALSIS (Atmosphere-Land Surface Interaction Scheme), is then coupled into CEMSYS4 (Computational Environmental Modelling System) to investigate the influences of atmosphere-ocean and atmosphere-land surface interactions ...

Brown, Kristina Anne

Recent Arctic warming and reduced summer sea ice extent have stimulated increased research into the role of sea ice in the high latitude carbon cycle. Using data collected on a number of field expeditions throughout the Arctic Ocean, I apply a multi-tracer approach to investigate the influence of the sea-ice life cycle on the biological and abiotic export of CO₂ into the sub-surface. The results of this study illuminate the role of sea ice in polar carbon cycling across the perennial sea ice re...

Basden, Stuart Jeffrey

Observing the movement in recent Christian theology, I examine the change in depth metaphors and theological works, as they move from tendencies of solidity and proposition-forming, to more fluid imaginations in their substance and style. I conduct an indirect comparison between John A.T. Robinson and Catherine Keller, engaging Buber, Tillich and Virginia Mollenkott, specifically focusing on themes of depth and working through a filter of social and ecological justice.Throughout the essay I ackn...

Wei, Jianwei

The radiance distribution provides complete information regarding the geometrical structure of the ambient light field within the ocean. A quantitative study of the radiance field in the dynamic ocean water is presented in this thesis work. The study starts with the development of a novel radiance camera for the measurement of the full spherical radiance distribution at the ocean surface and depth. Nonlinear response functions are designed and advanced radiometric calibrations are developed. The...

Mattern, Jann Paul

Realistic physical-biological ocean models pose challenges to statistical techniques due to their complexity, nonlinearity and high dimensionality. In this thesis, statistical data assimilation techniques for parameter and state estimation are adapted and applied to biological models. These methods rely on quantitative measures of agreement between models and observations. Eight such measures are compared and a suitable multiscale measure is selected for data assimilation. Build on this, two dat...

Oliver, Eric Curtis John

The Madden-Julian Oscillation (MJO) is the dominant mode of intraseasonal variability in the tropical atmosphere and provides global predictability on timescales that bridge the gap between weather and climate. The influence of the MJO on the ocean is explored with a combination of statistical analysis of observations using multivariate time series techniques, dynamical theory, and general circulation models with realistic forcing and bathymetry. The MJO is shown to have a significant and predic...

Rosell-Fieschi, Miquel

The velocity fields inferred from the trajectories of Argo floats have proven to be a valuable tool for observing the major ocean currents. The velocity fields can be used to examine statistical properties at regional and global scales, and to describe regional and global circulation patterns at temporal scales that range from months to years. The first application has been the statistical study of ocean velocities, in particular the analysis of the Gaussian character of the velocity PDFs. The A...

Evans, Kirk Eden.

No description available.

Trotman, George

No description available.

Blanding, Wayne Richard.

No description available.

Feller, David

Approved for public release, distribution unlimited / This Thesis addresses the question of Syria's pro-western tilt in foreign policy over the last few years. The most common argument, that the shift occurred because of the demise of the USSR (Syria's primary patron) is inaccurate. Rather, this thesis proves that changes in Syria's foreign policy began in the mid-198Os ,not in 1991, and were driven primarily by domestic economic factors, not by international structures. Syria's increasingly pro...

Edwards, Theodore M., Seidl, Mark F.

Approved for public release, distribution unlimited / This thesis investigates methods for constructing fielded jet engine reliability and maintainability (R&M) baselines, and methods for establishing R&M targets using benchmarking. The procedures developed can be applied with any fielded jet engine. Emphasis is placed on demonstrating the use of the Naval Aviation Logistics Analysis (NALDA) database in conjunction with existing spreadsheet software programs to develop frequency distributions an...

Baldwin, Richard Charles

Approved for public release, distribution unlimited / A mathematical model is developed for dispersion of a heated effluent from an ocean outfall. Input parameters include atmospheric and oceanic conditions and discharge characteristics. The model solves the steady-state, two-dimensional differential equation for non-conservative diffusion of heat in a moving fluid. The solution is calibrated and verified using data from surveys conducted at the Southern California Edison Company power plant at ...

Donaldson, William Jay, MacFarlane, Byron Noble

Approved for public release, distribution unlimited / An acoustic system was designed to investigate microbubble concentrations and distributions in the ocean. The system consisted of a one-dimensional standing-wave resonator and a reverberation sensor. Concentrations are determined by measurement of the variation in system Q and the change in reverberation level produced by the resonant bubble response. The resonator and the sensor, while functioning independently, both measure bubble concentra...

Navarro, Moisés M.

A novel technique to determine the phase velocity of long-wavelength shoaling waves is investigated. Operationally, the technique consists of three steps. First, using the Hilbert transform of a time series, the phase of the analytic signal is determined. Second, the correlations of the phases of analytic signals between two points in space are calculated and an average time of travel of the wave fronts is obtained. Third, if directional spectra are available or can be determined from time serie...

Nassopoulos, George

Approved for public release; distribution is unlimited. / After several years of research, the image theory has been found acceptable to solve the sound propagation problem within a wedge-shaped fluid overlying either a slow or a fast bottom. Some further observations where done in this research. The primary purpose was the development and computer application of a new analysis, the doublet analysis, based on the image theory. In this analysis, the features of the image theory are studied from a...

Schubert, David Michael

Acoustic Doppler velocities are combined with velocity profiles generated from XBT measurements to produce estimates of the flow field between Bermuda and the eastern coast of the United States. Repeated shipboard measurements along an ascending GEOSAT subtrack between Bermuda and Cape Cod allow study of rapid Gulf Stream Variability along the track, and comparison of sea surface and velocity measurements with those computed from the GEOSAT altimeter. The shipboard data were taken during two sep...

Davis, Charles A.

This thesis models induced magnetic fields from the motion of seawater in the Earth's magnetic field analytically and compares the results to arctic on-the-ice magnetic fluctuation measurements. The oceans have various types of internal motions, such as internal waves and turbulence. This motion of sea water, which is a conductor, in the earth's magnetic field induces a current density. The current density, in turn, induces its own magnetic field. This thesis models internal waves and upper laye...

Benedict, Tod D.

No description available.

Weddle, Charles A., OCEAN CURRENTS, PACIFIC OCEAN, OCEAN MODELS, WIND STRESS, STRESSES, MATHEMATICAL MODELS, WIND, SENSITIVITY, DEPTH, CIRCULATION, TROPICAL CYCLONES, LONGITUDE, INSTABILITY, CYCLONES, AIR WATER INTERACTIONS, MIXED LAYER(MARINE), IMAGES, ME

A primitive equation general circulation model with imbedded mixed layer physics has been used to investigate the response of the equatorial Pacific ocean to daily varying winds and westerly wind bursts. The major issue addressed by this study is the impact of daily varying winds, including westerly wind bursts, in the modeling of the tropical Pacific ocean and El Nino. In the developmental phase, the sensitivity of the model to the integration time step and the domain size were investigated. Th...

Strohm, Frederic M.

No description available.

Joyce, Michael D.

In a wedge shaped ocean, the method of images is used to develop an analytical approximation of the acoustic pressure field. Contemporary work develops acoustic doublets from a combination of the source and surface reflection image using simple dipole theory. The method of images is then used to sum the dipole images. This thesis matches dipole pairs to achieve a quadruplet expansion. A computer program using the derived quadruplet equation is then created to verify the results by comparing them...

Markopoulos, Marinos P.

No description available.

Lynch, Peter James

No description available.

Campbell, Jeffrey William

CIVINS / Part of the N.E. Pacific was studied to evaluate and use altimetric data from the Navy Geodetic Satellite GEOSAT. The zero-order accuracy of the major GEOSAT geophysical data record (GDR) channels was verified, and occasional gaps in the altimeter coverage were noted. GEOSAT's 17-day repeat orbit allowed use of collinear-track processing to create profiles of the difference between the sea surface height along a given satellite repeat, and the mean sea surface height along that repeat's...

Sheridan, Timothy F.

No description available.

Rowe, Elizabeth Anne

No description available.

Shay, Lynn K., Elsberry, Russell L.

No description available.

Brookins, A. Henry.

Approved for public release; distribution is unlimited. / A wave height transformation model is developed using surface roller theory. Roller energy production is included in the energy flux balance equation to predict rms wave height for randomly varying, irregular waves over arbitrary bathymetry. The dissipation function is defined using wave roller theory, where the area of the roller is defined from a simple bore analogy. The Rayleigh distribution is used to statistically describe wave heigh...

De Rouge, Etienne.

No description available.

Risch, Michael Scott

No description available.

Hooks, Maurice LeRoy.

No description available.