Index Catalog // ScholarsArchive@OSU

Topics in ocean turbulence : thermocouples, salt fluxes, and internal hydraulics

Creator:: Nash, Jonathan D.
Resource Type:: Dissertation

Numerical model investigations of wind-driven coastal circulation

Creator:: Cervantes, Brandy T.
Abstract:: The effects of wind forcing on coastal ocean circulation are studied using a numerical modeling approach. The first region of interest is on the North Carolina shelf, where the Coastal Ocean Processes (CoOP) Inner Shelf Study (ISS) took place during August - November 1994. ISS observations are used to initialize,...
Resource Type:: Dissertation

A numerical study of the upwelling circulation off central Chile

Creator:: Mesias, Jorge M.
Resource Type:: Dissertation

Changing export production in the Eastern Equatorial Pacific, 160 ka to present

Creator:: Kish, Stacy W.
Abstract:: The increase in modern atmospheric CO₂ concentration (360 ppm) from pre-industrial levels (280 ppm) raises concern over the impact of anthropogenic carbon dioxide input on atmospheric chemistry. For this reason, it is important to understand the natural fluctuations of atmospheric carbon dioxide in the past. The Vostok ice core record...
Resource Type:: Masters Thesis

Comparative study of the population dynamics, secondary productivity, and reproductive ecology of the euphausiids Euphausia pacifica and Thysanoessa spinifera in the Oregon upwelling region

Creator:: Gutierrez, Jaime Gomez
Abstract:: I compare the seasonal abundance variation, population dynamics, fecundity, egg hatching mechanism and success, and apostome ciliate parasites of the euphausiids Euphausia pac?fica and Thysanoessa spinfera from the Oregon coast, USA. Community structure and nearshore distributions were examined from bi-weekly oceanographic surveys (1970-1972). This region has a strong cross-shelf change...
Resource Type:: Dissertation

Long baroclinic planetary waves in a nonzonal vertically sheared mean flow

Creator:: Cerovecki, Ivana
Abstract:: We consider long planetary waves of annual period linearized about a steady, wind-driven subtropical (ST) gyre circulation. The circulation divides the gyre into an eastern zone (EZ) where only the surface layer is in steady motion and a western zone (WZ) where both the surface and the middle layer are...
Resource Type:: Dissertation

Relationships of in situ spectral absorption, pigment ratios and environmental parameters for phytoplankton assemblages in coastal waters

Creator:: Eisner, Lisa B.
Abstract:: In situ optical measurements of spectral absorption and beam attenuation provide information on the fine scale horizontal and vertical variations in phytoplankton pigments and other measures of phytoplankton photophysiology and ecology in coastal waters. Phytoplankton pigment ratios from discrete sample analyses with High Performance Liquid Chromatography were compared to in...
Resource Type:: Dissertation

Quantitative analysis of nearshore morphological variability based on video imaging

Creator:: Alexander, Patricia Soupy
Abstract:: In the past, classification systems for the analysis of morphodynamic variability have been developed in an attempt to understand large scale coastal behavior. The motivation behind the creation of these classification systems has been to provide a framework of analysis, in order to understand large scale response to seasonal variability,...
Resource Type:: Masters Thesis

Decomposition of absorption coefficients and decorrelation lengthscales of hydrographic and inherent optical properties in the Middle Atlantic Bight

Creator:: Simeon, Jennifer J.
Abstract:: This investigation is an exploration of the use of inherent optical properties towards further elucidation of coastal circulation processes occurring on the continental shelf and slope in the Middle Atlantic Bight, south of Cape Cod Massachusetts, during 14-Aug to 1-Sep 1996 and 25-Apr to 15-May 1997. Assessing the possibility of...
Resource Type:: Masters Thesis

Bacterioplankton in the Oregon upwelling system: distribution, cell-specific leucine incorporation, and diversity

Creator:: Longnecker, Krista
Abstract:: Marine bacterioplankton play an important role in global elemental cycles because they return carbon dioxide and nutrients to the biosphere as they reduce organic matter. Furthermore, marine bacterioplankton are not uniformly active, and subpopulations of the in situ community may be more or less active at any given time. Defining...
Resource Type:: Dissertation

The cross-equatorial structure of tropical instability waves in sea surface height

Creator:: Lyman, John M.
Abstract:: A linearized model with two vertical modes has been developed to understand observed characteristics of monthly variability in the Equatorial Pacific from TOPEX/POSEIDON measurements of Sea Surface Height (SSH). The 2-mode model is obtained from an equatorial beta plane model that has been linearized about a geostrophically balanced mean flow...
Resource Type:: Dissertation

Modeling studies of the coastal circulation off northern California

Creator:: Pullen, Julie D.
Abstract:: By implementing a series of mass-conserving nested high-resolution models down to approximately 1 km resolution that have realistic bathymetry, coastline, wind forcing and river run-off, the winter 1996-1997 shelf flow near Cape Mendocino, California, is simulated and compared with available observations from the Strata Formation on Margins (STRATAFORM) marine geology...
Resource Type:: Dissertation

Modeling studies of mesoscale circulation in the Gulf of California

Creator:: Martínez Alcalá, José Antonio
Abstract:: The mesoscale circulation in the Gulf of California is investigated using a numerical model (Princeton Ocean Model). Forced by satellite-derived winds, the circulation in the gulf shows a complex pattern dominated in the southern gulf by multiple eddies. Near the coast and in most of the north gulf, the circulation...
Resource Type:: Dissertation

Understanding the anodic mechanism of a seafloor fuel cell

Creator:: Ryckelynck, Natacha
Abstract:: Anoxic sediment overlain by oxic seawater establishes a voltage gradient on the order of 0.7-0.8V across the sediment-water interface. This study follows Reimers et al. (2001) and Tender et al. (2002) who reported the development of a seafloor fuel cell to harvest electrical energy from this potential difference. Prototype fuel...
Resource Type:: Masters Thesis

Right whale ecology in the northwest Atlantic ocean

Creator:: Baumgartner, Mark F.
Abstract:: The ecology of the North Atlantic right whale (Eubalaena glacialis) was examined at three spatial scales during the summer and early fall on their northern feeding grounds. The diving and foraging behavior of right whales was investigated at spatial scales of hundreds to thousands of meters by tagging right whales...
Resource Type:: Dissertation

Development of a rare earth element paleoproxy

Creator:: Haley, Brian Alexander, 1973-
Abstract:: This thesis describes the development of a rare earth element (REE) proxy for paleoceanographic studies of climate change. This work was done in three stages with the goal: (1) To develop a cleaning method that overcomes the problems of REE readsorption; (2) To measure pore water REEs for evaluation of...
Resource Type:: Dissertation

Numerical and assimilative studies of the equatorial Pacific cold tongue

Creator:: Perez, Renellys Christine
Abstract:: Numerical model and assimilation experiments were conducted in the tropical Pacific Ocean to obtain a better understanding of the processes that control the cold tongue surface mixed layer temperature balance during August 1999 to July 2004. The numerical model was first applied to test two hypotheses (asymmetric background currents and...
Resource Type:: Dissertation

Modeling studies of ocean circulation using inverse methods and bifurcation theory

Creator:: Vernieres, Guillaume
Abstract:: We present a study of the ocean circulation using state of the art numerical and data assimilation techniques. The second chapter of the thesis presents the development and application of generalized inversion to a simple dynamical model of Lake Kinneret. The intent was to develop the necessary tools to implement...
Resource Type:: Dissertation

Distribution and abundance of coastal fish and macro-invertebrates in the Galapagos Islands

Creator:: Figueroa, Diego
Abstract:: The Galapagos Islands, located off the coast of Ecuador, have a spatially diverse marine environment suitable for a variety of species with different climatic requirements. A year-long inventory program was carried out in 2000-2001 to provide baseline data on the abundances and distribution of coastal fish and macro-invertebrates. The purposes...
Resource Type:: Masters Thesis

Hydrothermal links between ocean plateau formation and global anoxia at the Cenomanian-Turonian boundary

Creator:: Snow, Laura J.
Abstract:: The Cretaceous was a period of extreme climatic conditions accompanied by major perturbations in ocean-atmosphere biogeochemical cycles. One of the most intriguing features is the sporadic interruption of normal marine pelagic sediment deposition by organic rich sediments deposited during oxygen-deficient conditions (ocean anoxic events OAEs). A current model for the...
Resource Type:: Masters Thesis

Studies on the spatial variability of phytoplankton physiology and biomass in the Oregon upwelling system

Creator:: Sanders, Rachel B.
Abstract:: The Oregon upwelling system is a region of high biomass and primary productivity as well as strong mesoscale variability. In order to examine the interaction of physical forcing and ecosystem dynamics, four 3-week sampling cruises were conducted in the Oregon upwelling system as part of the Northeast Pacific Global Ocean...
Resource Type:: Masters Thesis

A seasonal study of sediment reworking by Neotrypaea californiensis in Yaquina Bay, Oregon

Creator:: Fritz, Cara E.
Abstract:: A year-long field study was undertaken to investigate the influence of a number of physical and biological factors, specifically temperature, organic carbon content, and shrimp population dynamics on sediment reworking rates by the ghost shrimp Neotrypaea calforniensis. Because of its role as a structuring agent in estuaries along the West...
Resource Type:: Masters Thesis

The sediment response of a dissipative beach to variations in wave climate

Creator:: Haxel, Joseph H.
Abstract:: Using wave and wind data from nearby buoys and gauges, real time kinematic global positioning system (RTK-GPS) and light detection and ranging (lidar) topographic survey data, and a robust video record, we have quantified the Large Scale Coastal Behavior (LSCB) of a dissipative end member beach in the Pacific Northwest....
Resource Type:: Masters Thesis

Measuring surface longshore currents with an optical technique

Creator:: Chickadel, Carmine C.
Abstract:: Longshore currents are frequently occurring phenomena capable of transporting beach sediments, causing accretion and erosion of the shoreline. Forcing mechanisms are understood and well modeled for cases of alongshore homogeneous and monotonic bathymetry, yet the extension of these models to complex and irregular bathymetry sometimes fails. To test and improve...
Resource Type:: Masters Thesis

Spatial structure of the physical and biological distributions across the Antarctic Polar Front in austral spring and summer

Creator:: Howard, Cidney
Abstract:: Mesoscale surveys to examine the relationship between the physical processes and biological response along the Antarctic Polar Front (PF) were conducted as part of the US JGOFS Southern Ocean Program during austral spring and summer 1997/98. Multiple crossings of the PF near 170° W, using a towed undulating instrument, provided...
Resource Type:: Masters Thesis

Physical and chemical factors controlling the distribution of the major phytoplankton classes at the Antarctic Polar Front, 170 °W

Creator:: Mengelt, Claudia
Abstract:: This study was part of the Antarctic Environment and Southern Ocean Study (AESOPS) program, whose main goal was to investigate the role of the biota in the carbon flux from the atmosphere to the interior of the ocean. We quantified the abundance of the major phytoplankton classes and examined the...
Resource Type:: Masters Thesis

Laboratory investigations of the natural fluorescence of marine phytoplankton

Creator:: Laney, Samuel R.
Abstract:: The influence of nitrate availability and irradiance on phytoplankton natural fluorescence was investigated in laboratory cultures of the marine diatom Thalassiosira weissflogii (Bacillariophyceae). Two cultures of phytoplankton, differing only in the nitrate-limited growth rate, were compared to learn how increases in irradiance influences natural fluorescence. Instrumentation was developed for these...
Resource Type:: Masters Thesis

Blue whale (Balaenoptera musculus) vocalizations recorded in the North Pacific Ocean : geographic, seasonal and diel variation

Creator:: Stafford, Kathleen Mary
Resource Type:: Dissertation

Siberian-Arctic shelf surface-sediments: sources, transport pathways and processes, and diagenetic alteration

Creator:: Viscosi-Shirley, Carolyn
Abstract:: This thesis investigates lithogenic sediments on the Siberian Arctic shelf, their sources, modes of dispersal, transport pathways and post-depositional diagenetic alteration. Working with cores collected from the Chukchi, East Siberian and Laptev Seas, we characterize surface-sediment elemental chemistry and clay mineralogy. We identify five regions with endmember sedimentary compositions. Comparing...
Resource Type:: Dissertation

Oceanographic conditions around the Galápagos Archipelago and their influence on cetacean community structure

Creator:: Palacios, Daniel Mauricio
Abstract:: The objectives of this dissertation were to describe the complex oceanographic conditions around the Galápagos Archipelago (eastern equatorial Pacific), their seasonal variability, and their effects on patterns of cetacean occurrence. The physical and ecological factors leading to a plume of high phytoplankton biomass in the wake of the Galápagos were...
Resource Type:: Dissertation

The inherent optical properties of the oceans: from closure to prediction

Creator:: Barnard, Andrew Heath
Abstract:: Precise in situ measurement of the spectral absorption and scattering coefficients in several regions has revealed patterns in the distribution of the inherent optical properties on spatial scales that were previously unobtainable. The precision of the measurements was found to be consistent and unbiased across a variety of oceanic regimes...
Resource Type:: Dissertation

Microbial diversity of sulfide structures from hydrothermal vent sites at 9°N, Guaymas Basin and the Juan de Fuca Ridge

Creator:: Longnecker, Krista
Abstract:: The microbial diversity associated with sulfide structures from three different hydrothermal vent fields was examined using phylogenetic analysis based on the small subunit ribosomal RNA gene (16S rDNA). Samples were collected from sites at 9°N, Guaymas Basin and the Juan de Fuca Ridge and analyzed with denaturing gradient gel electrophoresis...
Resource Type:: Masters Thesis

Sediment accumulation and human impacts in Tillamook Bay, Oregon

Creator:: Styllas, Michael N.
Abstract:: Tillamook Bay is the second largest estuary on the Oregon coast, and concerns have been raised whether human induced impacts have been responsible for the perceived increase in sedimentation rates during the past century. Major land-use practices within the five watersheds of the Bay include logging, forest fires, the construction...
Resource Type:: Masters Thesis

Production and export of biogenic silica in the Southern Ocean

Creator:: Sigmon, Daniel E.
Abstract:: Dissolved silicic acid (Si(OH)4) and biogenic silica (BSiO2) concentrations were measured on four different cruises in the Southern Ocean along 1700 W from late October 1997 to mid-March 1998. These data were used to construct a vertically integrated Si budget in the surface layer from 58° to 68° S. Throughout...
Resource Type:: Masters Thesis

Sea surface height and geostrophic velocity variability in the California current system as observed from the TOPEX altimeter

Creator:: Righi, Dylan D.
Abstract:: Eight years (1994-2000) of data from the TOPEX/Poseidon satellite altimeter are used to investigate the variability of the sea surface height and geostrophic velocity of the California Current system. The TOPEX/Posiedon satellite measures SSH along an exact-repeat set of groundtracks with a 10-day repeat cycle. In the domain studied here...
Resource Type:: Masters Thesis

Exploring a fluorescence-based analytical method for Ba in natural waters and a field study of the major ion chemistry of Lake Issyk-Kul, Kyrgyzstan

Creator:: Qiu, Xuemei
Abstract:: Two separate research projects are described here. One involves development of a new analytical method for determination of Ba in seawater and other natural waters. The other is a collaborative field study of the chemistry of Lake Issyk-Kul, Kyrgyzstan. The method project explored an ion chromatography-fluorescence detection bench-top approach for...
Resource Type:: Masters Thesis

High-frequency measurements of total CO₂ : Method development and first oceanographic observations

Creator:: Bandstra, Leah M.
Abstract:: As concern grows about the long-term effects of increasing atmospheric CO₂ concentrations, it becomes increasingly important to understand the cycling of carbon on Earth, particularly in the dynamic marine reservoir. Gas exchange and relatively rapid ocean mixing times mean that the oceans play a significant role in determining the atmospheric...
Resource Type:: Masters Thesis

An X-radiographic study of the October 2000 Po River flood deposit, Italy

Creator:: Hunt, Louise
Abstract:: During October 2000 the Po River, Italy's largest river, experienced a historically significant flood, producing a deposit on the adjacent prodelta. In December 2000 an event-response study of the deposit was conducted, and during the ensuing 16 months three additional sampling cruises were conducted to study the subsequent evolution of...
Resource Type:: Masters Thesis

Foraminiferal assemblages preserved in surface sediments correspond to multiple environmental and preservation variables

Creator:: Ross, Ann E. Morey
Abstract:: Here we investigate the relationships between modern foraminiferal assemblages from Atlantic and Pacific surface sediment samples and multiple environmental properties including water column and preservation variables using Canonical Correspondence Analysis (CCA). CCA finds two fauna] dimensions that are highly correlated to the environmental variables included in the analysis, and then...
Resource Type:: Masters Thesis

Late pleistocene changes in the Peru current based on planktonic foraminifera

Creator:: Feldberg, Melissa J.
Abstract:: Planktonic foraminiferal faunal assemblages were used to estimate sea-surface temperatures (SST) in the southeast Pacific Ocean during the Last Glacial Maximum (LGM) and off the coast of Peru over the last 150,000 years. Temperatures along the eastern boundary of South America were 6-8° C cooler during the LGM than at...
Resource Type:: Masters Thesis

Microbial alteration of the seafloor

Creator:: Josef, Jennifer A.
Abstract:: In the early 1980's the first evidence of biological alteration of basalt glass (sideromelane) was published. Since that time additional evidence, including DNA staining, isotopic abundance and chemical mapping, has come to light suggesting that this unique alteration of glass can be attributed to microbial activity. Microbial alteration textures have...
Resource Type:: Masters Thesis

The impact of physical and biological properties on the erodibility of sediments along the western Adriatic Sea, Italy

Creator:: Stevens, Andrew W.
Abstract:: During two cruises in February and June of 2003, the erodibility of sediment along the western Adriatic Sea was measured using a "Gust erosion chamber". In addition, the surficial sediment properties were characterized through a suite physical and biological measurements including porosity, grain-size, inorganic carbon, organic carbon and colloidal carbohydrate....
Resource Type:: Masters Thesis

Modern and past climate variability in the eastern Pacific warm pool

Creator:: Benway, Heather M.
Abstract:: Westward transport of water vapor across the Panama Isthmus helps to maintain the salinity contrast between the Atlantic and Pacific Oceans, important in thermohaline circulation and global climate. Relatively low sea-surface salinities and a strong, shallow pycnocline in the eastern Pacific warm pool (EPWP) region near Central America reflect high...
Resource Type:: Dissertation

Production and partitioning of organic matter during simulated phytoplankton blooms

Creator:: Wetz, Michael S.
Abstract:: Few studies have examined the partitioning of organic matter in upwelling systems, despite the fact that these systems play a key role in carbon and nitrogen budgets in the ocean. We examined the production and partitioning of phytoplankton-derived organic matter in deck incubations off Oregon during the upwelling season. During...
Resource Type:: Masters Thesis

Characterization of organic matter quality and content in Columbia River suspended particulate matter by cupric oxide oxidation

Creator:: Alleau, Yvan M.
Abstract:: The organic content of the Columbia River suspended particulate matter (SPM) results from the input of autochthonous (phytoplankton) and allochthonous (terrestrial vascular plants) production. The contribution of these two sources appears seasonal and responds to factors such as rainfall, runoff, river flow, light and nutrients availability. While numerous studies have...
Resource Type:: Masters Thesis

Vertical distribution patterns of plankton and their relationship to physical factors over the continental shelf off Oregon

Creator:: Sutor, Malinda
Abstract:: Discrete layers of phytoplankton and zooplankton were observed over the Oregon continental shelf in summer and fall of 2001 and summer 2002 using optical and acoustical technologies and a pump sampling system. Layers of phytoplankton had steep vertical gradients which were associated with gradients in density and local peaks in...
Resource Type:: Dissertation

A systematic survey of the modeled optical properties of nonspherical marine-like particles

Creator:: Herring, Sean G.
Abstract:: The optical properties of randomly oriented, spheroidal marine particles are modeled using both numerical and analytical techniques. The optical properties examined are attenuation, scattering, absorption and backscattering. The optical properties are compared to those of equal-volume spheres. The optical properties of very small particles, relative to the wavelength of the...
Resource Type:: Masters Thesis

Ecological interrelationships between summer resident gray whales (Eschrichtius robustus) and their prey, mysid shrimp (Holmesimysis sculpta and Neomysis rayi) along the central Oregon coast

Creator:: Newell, Carrie
Abstract:: The ecological interaction between the largest coastal predator, the gray whale (Eschrichtius robustus) and the most abundant shallow water marcrozooplanktonic prey, mysids, were examined in a poorly-understood predator-prey relationship along the central Oregon coast. From 2002-2008, 83 seasonal gray whales were identified. These whales returned each year around Memorial Day...
Resource Type:: Masters Thesis

Zooplankton of the Galapagos Islands

Creator:: Figueroa, Diego
Abstract:: The marine climate of the Galapagos is spatially and seasonally heterogeneous. A taxonomically comprehensive study of Galapagos zooplankton has never been done. This study is an initial effort to establish the distribution and community structure of zooplankton in the Archipelago. I collected zooplankton samples by vertical tows over the Galapagos...
Resource Type:: Dissertation

Diurnal wind-driven processes on the northern Monterey Bay inner shelf

Creator:: Suanda, Sutara H.
Abstract:: In the summer of 2007, a biophysical experiment was conducted to identify physical processes that determine the delivery of invertebrate larvae and juvenile rockfish to rocky intertidal and kelp forest communities in northern Monterey Bay, California. The experiment was sponsored by the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO)...
Resource Type:: Masters Thesis

The Costa Rica Dome : a study of physics, zooplankton and blue whales

Creator:: Matteson, Robyn S.
Abstract:: At the Costa Rica Dome (CRD), upwelling associated with cyclonic circulation and the presence of a shallow thermocline support a highly productive biological habitat, exploited by marine fauna at several trophic levels. During January 2008, a cruise to the CRD by the R/V Pacific Storm was conducted to relocate blue...
Resource Type:: Masters Thesis

Bioenergetics individual based model explorations of juvenile coho salmon growth during their first summer on the Oregon shelf

Creator:: Reser, Brendan Alexander
Abstract:: Salmon survival and eventual recruitment success have long been thought to be determined within the first summer following ocean migration. Juvenile growth during this period is largely influenced by ocean conditions such as temperature, prey availability, abundance, and quality. Shifts in these conditions due to climatic perturbations are particularly prevalent...
Resource Type:: Masters Thesis

Nitrogen isotopes in a global ocean biogeochemical model : constraints on the coupling between denitrification and nitrogen fixation

Creator:: Somes, Christopher J.
Abstract:: We present a new nitrogen isotope model incorporated into the three-dimensional ocean component of a global Earth System Climate Model designed for millennial timescale simulations. The model includes prognostic tracers for the stable nitrogen isotopes, ¹⁴N and ¹⁵N, in the nitrate (NO₃ˉ), phytoplankton, zooplankton, and detritus variables of the marine...
Resource Type:: Masters Thesis

Glacial to holocene watermass and continental weathering reconstructions from the Southeast Pacific

Creator:: Muratli, Jesse M.
Abstract:: Sediments of the central Chile margin record changes in ocean circulation and continental erosion associated with large–scale climate change. Here Antarctic– influenced Southern Ocean currents flow equatorward, forming a link between the high– and low–latitude oceans. Part of this link, Antarctic Intermediate Water, is an important conduit that ventilates South...
Resource Type:: Masters Thesis

Observations on the evolution of shoaling nonlinear internal waves in Massachusetts Bay using shipboard X-band radar

Creator:: Nelson, Brian G.
Abstract:: During four cruises in July and September of 2008 and 2009, the shipboard X-band radar was tuned to detect the modulated bands of surface roughness caused by converging and diverging currents associated with high-frequency nonlinear internal wave (NLIW) packets. The data collected was used to quantify the propagation direction (ϴp),...
Resource Type:: Masters Thesis

Mathematical approaches to the physics of mesoscale oceanography

Creator:: Early, Jeffrey J.
Abstract:: The long-term evolution of Gaussian eddies is studied in an equivalent barotropic model using both linear and nonlinear quasi-geostrophic theory in an attempt to understand westward propagating satellite altimetry tracked mesoscale eddies. By examining both individual eddies and a large basin seeded with eddies, it is shown that long term...
Resource Type:: Dissertation

Nonlinear internal waves on the continental shelf

Creator:: Shroyer, Emily L.
Abstract:: The properties and evolution of nonlinear internal waves (NLIWs) depend upon the background conditions within which waves form, propagate, and dissipate. As a result, the NLIW field on the New Jersey shelf displayed dramatic variability during the Shallow Water 2006 experiment. Wave variability was exhibited by 1) amplitudes that ranged...
Resource Type:: Dissertation

Observing the coastal ocean with HF radar

Creator:: O'Keefe, Sheila
Abstract:: Coastal-based high-frequency (HF) radar systems are an increasingly used tool for measuring surface currents in the coastal ocean. These systems provide a spatial and temporal resolution not achievable with other methods. Standard-range sites typically generate hourly maps of surface currents on a 2km grid extending approximately 50km from shore while...
Resource Type:: Masters Thesis

Deformation, fluid venting, and slope failure at an active margin gas hydrate province, Hydrate Ridge Cascadia accretionary wedge

Creator:: Johnson, Joel E.
Abstract:: During the last 15 years, numerous geophysical surveys and geological sampling and coring expeditions have helped to characterize the tectonic setting, subsurface stratigraphy, and gas hydrate occurrence and abundance within the region of the accretionary wedge surrounding Hydrate Ridge. Because of these investigations, Hydrate Ridge has developed as an international...
Resource Type:: Dissertation

Ecology of Greenland halibut (Reinhardtius hippoglossoides) during the early life stages in the Eastern Bering Sea and Aleutian Islands

Creator:: Sohn, Dongwha
Abstract:: Greenland halibut (Reinhardtius hippoglossoides) have decreased in the eastern Bering Sea and Aleutian Islands since the 1970s. The reasons behind the poor recruitment are unknown, and important knowledge gaps of the ecology of the early life stages have been identified. The objectives of thesis research were (1) to examine geographic...
Resource Type:: Masters Thesis

Deconvolving the sedimentary phases of barium using flow-through time-resolved analysis

Creator:: Hsieh, Chih-Ting
Abstract:: The distribution of barite (BaSO₄) in marine sediments has long been studied as a proxy for paleoproductivity. While pure barite is known to be a stable mineral in oxic sediments, it is also known that variations in the Sr/Ba ratio influence its solubility and liability during early diagenesis. To extract...
Resource Type:: Masters Thesis

Determination of unsaturation-, growth phase-, and growth rate-dependent hydrogen isotopic fractionation in C₃₇ alkenones produced by Emiliania huxleyi

Creator:: Wolhowe, Matthew D.
Abstract:: Recent works have investigated use of the hydrogen isotopic composition of C₃₇ alkenones (δD[subscript K37s]), lipid biomarkers of certain haptophyte microalgae, as an independent paleosalinity proxy. I discuss herein the factors impeding such an application and identify the potential alternative use of δD[subscript K37s] measurements as a proxy for non-thermal,...
Resource Type:: Masters Thesis

Development of 2D models to estimate nearshore bathymetry and sediment transport

Creator:: Splinter, Kristen D.
Abstract:: We examine the interactions and feedbacks between bathymetry, waves, currents, and sediment transport. The ﬁrst two pro jects focus on the use of remote sensing techniques to expand our knowledge of the nearshore. Due to the plethora of snap-shot data that is available from satellites and their distribution via Google...
Resource Type:: Dissertation

Field validation of a nearshore circulation model for alongshore-nonuniform flows

Creator:: Wilson, Gregory W.
Abstract:: We investigate, theoretically and experimentally, the problem of modeling depth-integrated (2DH) surf zone circulation on an alongshore-nonuniform natural beach, with waves approaching from an arbitrary angle. An approximate theoretical model is developed, which captures the important effect of advection in the alongshore dynamics, and shows that a nondimensional parameter Re[subscript]s...
Resource Type:: Masters Thesis

An examination of the form and variability of manganese oxide in Columbia River suspended material

Creator:: Covert, Paul Allister
Abstract:: Suspended particulate matter (SPM) in the Columbia River is a mixture of particles of several origins having varying physical and biogeochemical properties. The relative abundances of these freshwater particles changes with season and apparently also with tide. Prior investigation has quantified seasonal variation of organic material in both the Columbia...
Resource Type:: Masters Thesis

Utilization of natural and supplemental biofuels for harvesting energy from marine sediments

Creator:: Nielsen, Mark E.
Abstract:: A benthic microbial fuel cell (BMFC) is an electrochemical device that generates current from the redox gradient at the sediment-water interface. Early prototypes had anodes buried in anoxic sediments and cathodes in overlying water. The BMFCs described in this dissertation are based on a chamber design that enables the use...
Resource Type:: Dissertation

The South Atlantic Ocean response to local and remote forcings

Creator:: Fetter Filho, Antonio F. H.
Abstract:: The local and remote sources of variability of the South Atlantic Ocean are investigated using a set of numerical experiments and satellite data. A global, eddy-permitting, numerical simulation is analyzed to investigate the dynamical links between the Antarctic Circumpolar Current (ACC) and the Malvinas Current (MC). The model results indicate...
Resource Type:: Dissertation

An investigation into nitrogen uptake by Emilania huxleyi during continuous darkness

Creator:: Royer, Ida M.
Abstract:: Experiments were conducted with two strains of the coccolithophorid Emiliania huxleyi. Previous experiments with CCMP1742 and 372 at a light intensity of 60 µEin/m²-s showed that during five-day periods of continuous darkness, strain 1742 was taking up nitrate from the media while strain 372 was not. The nitrate uptake in...
Resource Type:: Masters Thesis

The spectral backscattering properties of marine particles

Creator:: Whitmire, Amanda L.
Abstract:: The inherent and apparent optical properties of different ocean regimes are the basis for all optical remote sensing of the ocean. Ecological information derived from remote sensors therefore relies on having a detailed understanding of how particulate backscattering and absorption contribute to the bulk optical signal. The absorption characteristics of...
Resource Type:: Dissertation

The influence of early diagenesis on trace element and molybdenum isotope geochemistry

Creator:: Poulson, Rebecca L.
Abstract:: This thesis investigates the influence of early diagenesis on trace metal and molybdenum isotope behavior in marine and lacustrine environments. Chapter one is a synthesis of previous research in all the marine environments investigated, providing an essential geochemical context for interpreting the observed behavior of Mo in these settings. Chapter...
Resource Type:: Dissertation

Prokaryotes associated with marine crust

Creator:: Mason, Olivia Underwood
Abstract:: Oceanic crust covers nearly 70% of the Earth's surface, of which, the upper, sediment layer is estimated to harbor substantial microbial biomass. Marine crust; however, extends several kilometers beyond this surficial layer, and includes the basalt and gabbro layers. In particular, the basalt layer has high permeabilities which allows for...
Resource Type:: Dissertation

Silicon biogeochemistry in the open-ocean surface waters : insights from the Sargasso Sea and equatorial Pacific

Creator:: Krause, Jeffrey W.
Abstract:: Diatoms are a ubiquitous group of plankton responsible for 20-40% of oceanic primary production, and a higher fraction of organic matter export to the ocean interior. Diatoms actively transport dissolved inorganic silicon into their cells, and through the process of silicification (i.e. biogenic silica production) they build tough and intricate...
Resource Type:: Dissertation

Distribution, structure, and function of marine ecological communities in the northern California Current upwelling ecosystem

Creator:: Reese, Douglas Charles
Abstract:: Within systems characterized by substantial spatial and temporal variability, abundances of organisms tend to be higher in localized areas. Within the northern California Current system, the identification of such marine, biological hotspots would be of great importance to resource managers, conservationists, and research planners, and is consequently a growing area...
Resource Type:: Dissertation

Mapping semi-regular autonomous underwater vehicle glider observations onto a cross-shelf section

Creator:: Peery, Andrew Tristan
Abstract:: Two Autonomous Underwater Vehicle Gliders have alternated continuous sampling of a 45-nautical mile transect line (the Newport Hydrographic Line) across the Oregon continental shelf since April, 2006. Strong currents (>25cm/s) push the gliders off their trajectories as they survey this transect line, preventing them from sampling the historically occupied stations...
Resource Type:: Masters Thesis

Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current

Creator:: Keister, Julie Eileen
Abstract:: In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal...
Resource Type:: Dissertation

Geochemical and helium isotopic variability within the Lau Basin

Creator:: Goddard, Charlotte Ives
Abstract:: This research incorporates geochemical and helium isotopic analyses of Lau Basin volcanic glasses, along with helium isotopic analyses of water column hydrothermal plumes to better understand the processes that control the formation and evolution of this backarc basin. Lavas newly collected from the four southernmost segments of the Valu Fa...
Resource Type:: Dissertation

Characterizing the habitat and diving behavior of satellite-tagged blue whales (Balaenoptera musculus) off California

Creator:: Irvine, Ladd
Abstract:: This study was designed to identify and characterize areas of concentrated use and diving behavior of blue whales (Balaenoptera musculus) off the California coast. During the summer of 2004, thirteen blue whales were tagged with implantable Telonics ST-15 Argos satellite-monitored radio tags and five were tagged with Telonics ST-21 Argos...
Resource Type:: Masters Thesis

Geochemical cycling in a Pacific Northwest estuary (Tillamook Bay, Oregon, USA)

Creator:: Colbert, Debbie L.
Abstract:: This thesis investigates the behavior of major inorganic nutrients (P, N, Si), trace metals (Mn, Fe), and alkaline-earth metals (Ba) within Tillamook Bay over seasonal cycles and under a range of river discharge conditions from October 1997 through December 1999. Located in the Pacific Northwest region, Tillamook Bay is an...
Resource Type:: Dissertation

El Nino related variations in nutrient and chlorophyll distributions off Oregon

Creator:: Corwith, Holly L.
Abstract:: The Oregon continental shelf waters are typically characterized by four to five major upwelling events that occur between May and October. The upwelled water is rich in nutrients, which fuels an increase in phytoplankton biomass. The onset of El Nino, however, can disrupt the normal physical processes along the Oregon...
Resource Type:: Masters Thesis

Remote measurements of waves and currents over complex bathymetry

Creator:: Chickadel, Carmine C. (Carmine Christopher)
Abstract:: Waves are the primary input of energy in the nearshore region, and together with the currents forced through the transfer of momentum that occurs during the wave breaking process they are the principal mechanism for sediment transport in the nearshore. The basic physics of waves and currents are thought to...
Resource Type:: Dissertation

Remote sensing of radiation stress gradients from optical imagery

Creator:: Killian, Jason R.
Abstract:: Wave-induced circulation is the defining characteristic of the nearshore. Within this region, the constant feedback cycle between incoming waves, wave-generated currents, and the mobile sediment bed is responsible for the evolution of complex patterns in nearshore and beach morphology. Central to our understanding of this system is knowledge of the...
Resource Type:: Masters Thesis

Surface wind modification near mid-latitude ocean fronts : observational and dynamical analysis

Creator:: O'Neill, Larry W.
Abstract:: Interactions between surface winds and meanders in mid-latitude sea surface temperature (SST) fronts with horizontal length scales of 100-1000 km are investigated from satellite observations and numerical simulations. Observations from the Sea- Winds scatterometer on the QuikSCAT satellite show that the magnitude, direction, curl, and divergence of the surface wind...
Resource Type:: Dissertation

Mantle melting and heterogeneity along mid-ocean ridges : insight from basalt geochemistry along axial depth and morphologic gradients for intermediate spreading rate systems

Creator:: Russo, Christopher J.
Abstract:: This investigation focuses on gaining a better understanding of the complex relationship between melt generation, source variability and mid-ocean ridge morphology. The approach adopted here uses a variety of geochemical techniques to evaluate the ability of 'global' models to predict regional scale geochemical variability associated with axial depth and axial...
Resource Type:: Dissertation

The fluvial response to glacial-interglacial climate change in the Pacific Northwest, USA

Creator:: VanLaningham, Sam J.
Abstract:: This research focuses on the development of new techniques to explore terrestrial-ocean climate linkages along the Pacific Northwest-northeast Pacific Ocean margin. This is done by investigating river response to climate change and by unraveling this history preserved in continental margin sediments. A significant component of this work centers on developing...
Resource Type:: Dissertation

Inner-shelf circulation off the central Oregon Coast

Creator:: Kirincich, Anthony R.
Abstract:: Inner-shelf circulation and mechanisms of across-shelf transport of water masses were examined using seven years of observations collected by the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) program, a long-term monitoring effort along the central Oregon coast. Since 1998, moored velocity and hydrographic measurements have been obtained during the...
Resource Type:: Dissertation

Reconstructing salinity conditions in Nares Strait (Canadian Archipelago) from stable isotope profiles in bivalve shells

Creator:: Zima, Daniela
Abstract:: Nares Strait is one of three main passages of the Canadian Archipelago that channels freshwater from the Arctic Ocean to the North Atlantic. There are very few observations regarding the role of this region on the present day Arctic freshwater budget, and even less regarding the changes in freshwater fluxes...
Resource Type:: Masters Thesis

Development of an autonomous in-situ instrument for long-term monitoring of Cu(II) in the marine environment

Creator:: Holm, Christopher E.
Abstract:: An autonomous, in-situ instrument was developed to detect dissolved copper in seawater, suitable for deployment on time scales from weeks to months. A commercially available in-situ nitrate analyzer (YSI 9600) was adapted to measure copper (II) in seawater by chemiluminescence. Modifications included construction of a photomultiplier (PMT) based detector and...
Resource Type:: Masters Thesis

Phosphorus physiology and environmental forcing of oceanic cyanobacteria, primarily Trichodesmium spp.

Creator:: White, Angelicque E.
Abstract:: The biological transformation of dinitrogen gas (N2) into combined forms(termed N2 fixation) by certain genera of oceanic cyanobacteria represents the largest incoming flux of nitrogen to the global ocean. As such, biological nitrogen fixation plays a significant role in the regulation of oceanic productivity and the export of carbon and...
Resource Type:: Dissertation

Quantifying linear disturbance growth in periodic and aperiodic systems

Creator:: Wolfe, Christopher Lee
Abstract:: The mathematical and physical connections between three different ways of quantifying linear predictability in geophysical fluid systems are studied in a series of analytical and numerical models. Normal modes, as they are traditionally formulated in the instabilities theories of geophysical fluid dynamics, characterize the asymptotic development of disturbances to stationary...
Resource Type:: Dissertation

Diffuse deformation patterns along the North American plate boundary zone, offshore western United States

Creator:: Chaytor, Jason D.
Abstract:: Plate boundaries are commonly regions of complex, diffuse deformation with the motion across the boundary accommodated by numerous structural systems, rather than being narrow, discrete zones of deformation. One such boundary occurs where the North American plate makes contact with Juan de Fuca, Gorda, and Pacific plates along the west...
Resource Type:: Dissertation

Seconds to hour scale photosynthetic responses in marine microalgae

Creator:: Laney, Samuel R.
Abstract:: Our view of phytoplankton has historically revolved around their inability to control their location in space. The term phytoplankton itself underscores this particular difference between phytoplankton and their sessile terrestrial counterparts. Yet there are other differences between land plants and the phytoplankton that are perhaps equally important, beyond this sessile-planktonic...
Resource Type:: Dissertation

Dynamics of organic matter production and degradation during coastal diatom blooms

Creator:: Wetz, Michael S.
Abstract:: Experiments were designed to answer key questions about diatom-derived organic matter cycling (i.e., production and degradation) in coastal systems. Dissolved organic matter (DOM) production was examined in axenic batch cultures of five diatom species. Dissolved organic carbon (DOC) release rates varied between species, but were significantly higher for all species...
Resource Type:: Dissertation

Late Quaternary paleoceanography of the Northeast Pacific and Atlantic Oceans based on diatom transfer functions

Creator:: Lopes, Cristina Isabel Coelho Dias
Abstract:: Modern upwelling conditions and corresponding oceanographic properties are investigated and reconstructed for the Late Quaternary. The oceanographic conditions considered influence diatom ecology and the record of fossil diatom frustules in the sediments. Diatoms from modern sediments are evaluated as paleoceanographic proxies and transfer functions (TFs) are calibrated using the Imbrie...
Resource Type:: Dissertation

Impact of tropical instability waves on nutrient and chlorophyll distributions in the equatorial Pacific

Creator:: Evans, William Wiley
Abstract:: Tropical instability waves (TIWs) are prominent seasonal features in both the equatorial Pacific and Atlantic Oceans. This work quantifies their role in modulating the distributions of nutrients and phytoplankton biomass. Using an eight year record of biannual ship observations along the Tropical Atmosphere Ocean (TAO) buoy array, cruise sections crossing...
Resource Type:: Masters Thesis

Submarine plateau volcanism and Cretaceous Ocean Anoxic Event 1a : geochemical evidence from Aptian sedimentary sections

Creator:: Walczak, Paul S.
Abstract:: Marine sediments exceptionally rich in organic carbon, known as black shales, occur globally but intermittently in well correlated Cretaceous successions. The presence of black shales indicates that sporadic, ocean-wide interruption of normal respiration of marine organic matter during oxygen-deficient conditions has occurred. Submarine volcanism on a massive scale, related to...
Resource Type:: Masters Thesis

Contribution of cold seep barite to the barium geochemical budget of a marginal basin

Creator:: McQuay, Erica L.
Abstract:: Large barite (BaSO4) structures mark cold seeps in the southern San Clemente Basin. Barium flux to San Clemente sediments is two to three times greater than fluxes measured in surrounding California Borderland basins. Analyses of sediment trap material, water column samples, sediments and pore water indicate that expected bariumbearing mineral...
Resource Type:: Masters Thesis

Primary production dynamics in the North Pacific subtropical gyre

Creator:: Corno, Guido
Abstract:: The North Pacific subtropical gyre (NPSG), once considered to be a biological desert due to low primary production (PP) and its associated variability, has been found more productive and variable than previously thought. The environmental conditions controlling this relatively high PP variability are yet to be elucidated, despite important implications...
Resource Type:: Dissertation

Design, assessment, and future implications of the Multiple Enzyme Analyzer (MEA), a tool for in-situ monitoring of marine microbial activity

Creator:: Jaeger, Stephanie A.
Abstract:: The microbial loop plays a crucial role in remineralization of organic matter and fuels recycled production in the aquatic environment. The capability of microbes to utilize particular compounds can be examined through their ectoenzyme (found outside the cell) activities using fluorogenic substrate analogs. These catalysts hydrolyze polymers otherwise too large...
Resource Type:: Masters Thesis

Coastal ocean response to alongshore variations in topography and wind forcing

Creator:: Castelao, Renato Menezes
Abstract:: The effects of alongshore variability in topography (banks and capes) and spatial variability in the wind forcing, including the wind-stress curl, on coastal ocean circulation are studied using a combination of observations and model simulations. Satellite sea surface temperature observations are used to describe the seasonal evolution of temperature fronts...
Resource Type:: Dissertation

An empirical statistical model relating winds and ocean surface currents : implications for short-term current forecasts

Creator:: Zelenke, Brian Christopher
Abstract:: An empirical statistical model is developed that relates the non-tidal motion of the ocean surface currents off the Oregon coast to forecasts of the coastal winds. The empirical statistical model is then used to produce predictions of the surface currents that are evaluated for their agreement with measured currents. Measurements...
Resource Type:: Masters Thesis

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