PURPOSE: To determine physical, plankton and nutrient/chemical conditions over the continental margin for climate change studies in NE Pacific. In particular, to make CTD and CTD/rosette and net tow stations along 5 lines (off Newport, Heceta Head, Coos Bay, the Rogue River and Crescent City, OR, to deploy drifters at...
Effective watershed restoration planning and prioritization is often very difficult because decision making typically involves a large number of alternatives evaluated on the basis of multiple and often conflicting technical, social, economic, and environmental objectives and criteria. In order to solve such complex decision making problems, multiobjective decision making (MODM)...
We map the regional physiography and surficial lithology (Surficial Geologic Habitat or
SGH) over the continental margin of Oregon. This thesis develops, describes, and
implements an iterative interpretive method to map seafloor habitat types from disparate
geological and geophysical datasets including: bathymetric images, sidescan sonar
images, seismic reflection profiles, sediment...
Noimative invasive species pose a growing threat to living aquatic resources in the United States. Shipping particularly use of ballast water represents a major pathway of introduction for these species and in 1996, Congress established a program of baseline surveys to measure the effectiveness of ballast water management. This report...
Sauvie Island lies at the confluence of the Columbia River and the Willamette River near Portland, Oregon. Flooding, erosion, and deposition of sediments have been part of the natural evolution of the island. However, with the construction of multiple dams in the Columbia River Basin, levees, and hardening of upstream...
The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted to learn why the Pacific lamprey (Lampetra tridentata), a culturally and ecologically important species, was declining in the streams within their native land area....
The Mars Pathfinder (MPF) arrived on the Martian surface on 4 July 1997 to become only the third successful landed mission to Mars, recording surface meteorological data intermittently over a period of 83 Martian days ("sols"). The in situ observations made by the MPF meteorology (MET) experiment were recorded at...
Dramatic declines in many species of demersal fishes off the West Coast have resulted in the designation of nine commercially important species as being overfished. While the causes of those declines are not clearly understood, the fact remains that a paucity of life history and abundance data exists for many...
Cloud reflectivity is a function of cloud liquid water content and droplet number concentration. Since cloud droplets form around pre-existing aerosol particles, cloud droplet number concentration depends on the availability of particles that can serve as cloud condensation nuclei. Given constant liquid water amount, increased availability of cloud condensation nuclei...
The atmospheric radiative transfer model MOCARAT was developed and is presented in this thesis. MOCARAT employs a Monte Carlo Technique for the accurate modeling of band radiances and reflectances in an atmospheric system with a ruffled ocean surface as a lower boundary. The atmospheric radiative transfer is modeled with consideration...
A variety of general circulation model experiments are performed to investigate the influence of seasonality and topography on the strength of baroclinic eddies in the Martian atmosphere. Three different models are used: a full physics model, a simplified physics model, and a zonally symmetric simplified physics model. All three models...
This study concentrates on analysis of LongEZ aircraft data taken offshore of the Atlantic Coast of the United States. Due to the land structure of the region, it was possible to isolate the effect of narrow land on air as it flows offshore. The narrow land (Outer Banks) separates inland...
The Penn-State/NCAR MM5 mesoscale model was adapted for mesoscale simulations of the Martian atmosphere (the OSU MMM5). The NASA Ames Mars GCM provides initial and boundary conditions. High-resolution maps for albedo, thermal inertia and topography were developed from Mars Global Surveyor (MGS) data; these baseline maps are processed to appropriate...
The atmospheric response to the oceanic forcing in the eastern Pacific along the northern equatorial sea surface temperature (SST) front is investigated in terms of sensible and latent heat flux during the 6-month period 28 July 1999 through 27 January 2000. Of particular interest is the atmospheric boundary layer (ABL)...
The Indian Ocean Experiment (INDOEX) had as a primary objective
determining the radiative forcing due to anthropogenic aerosols over
climatologically significant space and time scales: the Indian Ocean during the
winter monsoon, January-March. During the winter monsoon, polluted, low-level
air from the Asian subcontinent blows over the Arabian Sea and...
A modeling study is undertaken to better understand the physics of katabatic flows. This study is divided into three topics; a comparison between a large eddy simulation (LES) and a mesoscale model of katabatic flows, a sensitivity study of katabatic flows to various physical parameters, and an investigation into the...
In the past, sharks, skates and ray species have mainly occurred in incidental fisheries. Now they are increasingly being directly targeted due to the depleted status of traditionally targeted species. The life history characteristics of many elasmobranch species make them more sensitive to high rates of fishing mortality. The combination...
The warm pool region of the western tropical Pacific is of particular interest to atmospheric dynamics because it represents a significant source of energy to the atmosphere. A better understanding of heat transfer driven by mesoscale and turbulent circulations within this region could lead to improved global circulation models, and...
In the equatorial Pacific Ocean, earthquakes are used as an indicator of tectonic stress for normal faults in the Galapagos Spreading Center, transform faults along the East Pacific Rise and thrust faults in the Middle American subduction zone. Linkages between seafloor tectonic processes and oceanographic and lunar conditions were explored...
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,...
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...
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...
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...
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...
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,...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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....
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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....
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...
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...
A satellite-derived Climatology of Global Ocean Winds (COGOW) on a 0.5° latitude by 0.5° latitude grid is presented based on 5-years (August 1999 July 2004) of measurements from the SeaWinds scatterometer that was launched on 19 June 1999 onboard the QuikSCAT satellite. SeaWinds is an active microwave radar that estimates...
This study reports on the creation and testing of a model concept-mapping process that will aid the development and documentation of ocean science educational content of The Science and Math Investigative Learning Experiences (SMILE) Program, a pre-college science and math enrichment program based at Oregon State University. The project uses...
Atmospheric boundary layers become stably stratified at night over land when the surface becomes colder than the air layer above. In stable nocturnal boundary layers (SNBL), turbulence becomes weak and intermittent, terrain-induced phenomena such as drainage currents or gravity-waves emerge and the surface heterogeneity is enhanced. Because of their complexity...
Advanced Very-High Resolution Radiometer 4-km data were collected over the northeast Atlantic for May-August, 1995-1999. Aerosol optical depth was retrieved in cloud-free pixels. In pixels containing clouds from only single-layered, low-level systems, a retrieval scheme that accounts for partly-cloudy pixels was used to retrieve: cloud optical depth, droplet effective radius,...
Lingcod (Ophiodon elongatus) are known to utilize certain estuaries along the Pacific coast of the United States, but the importance of these habitats to the coast-wide population is not well understood. In this study, general patterns of estuarine habitat use were assessed by tracking the movement of sub-adult and adult...
Behavioral studies of populations provide clues as to what influences their
movements and life history strategies. This is an area of study that has been
underutilized in research surrounding the declining western stock of Steller sea
lions, Eumet opias jubatus, particularly with regards to haulout behaviors. During
the time of...
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...
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...
Recent observational programs to understand the coastal ocean, like the Oregon Coastal Ocean Observing System (OrCOOS) are under development (www.orcoos.org). A challenge in facing observing systems is achieving spatial and temporal coverage at scales that are useful for ocean modeling. Observational buoys are relatively few and towed arrays and gliders...
This project examined a watershed council sponsored volunteer estuary water quality monitoring program, from initial implementation to program status five years later. In addition, literature research and interviews with estuarine experts were conducted in an attempt to devise strategies to strengthen estuary water quality monitoring programs within the state of...
Loss of wetlands within Oregon has led to strong interest in restoring wetlands that once existed. Restoration practitioners are currently using knowledge they have gained from many years of working with wetlands to design and carry out restoration projects. There is much variability between tidal wetlands within coastal
Oregon and...
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...
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...
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)...
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...
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...
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...
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...
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),...
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...
Since 2006 Oregon has promoted the development of wave energy off its coast. While the state may be well suited for the technology because of an abundant wave resource and supporting coastal infrastructure there remain potential barriers to implementing this policy, including uncertainties about the technology and concerns for impacts...
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...
This Master's Degree project is intended to document historical ecological conditions and land use histories during the past 150 years for selected Oregon watersheds and tidal wetland sites. The sites are the subject of current research into the ability of tidal wetlands to provide rearing habitat and prey for juvenile...
This study aims to improve knowledge of how suspended particulate matter (SPM) affects hydrophobic contaminant transport in the lower Columbia River and its estuary, using polycyclic aromatic hydrocarbons (PAHs) as model compounds. It is hypothesized that PAHs are transported to the estuarine turbidity maximum (ETM), a prime feeding zone in...
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...
North Pacific albacore (Thunnus alalunga) is a highly migratory and
commercially valuable species of tuna. All stock assessments and management
decisions for North Pacific albacore are presently based on the assumption of a single,
uniform stock. However, a growing body of evidence from diverse sources suggests
that there are two...
Anecdotal evidence suggests many Pacific Northwest estuaries are filling with sediment due to historical logging activities in upstream watersheds. Using the Siletz River estuary as a case study, this research began by analyzing timber harvest and discharge records of the Siletz River watershed, and found that increased timber harvest coincides...
If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts to identify Essential Fish Habitat (EFH) for the 82 groundfish species managed by the Pacific Fishery Management Council along the West Coast...
Ocean observing groups are currently making efforts to work with well-defined end-user groups, like boaters and fishermen, to provide meaningful and effective real-time data (RTD) products and visualizations. However, providing meaningful data products for undefined groups such as the general public is not straightforward. In Oregon, several industry, science, and...
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...
The 2007 Intergovernmental Panel on Climate Change assessment established that the effect of clouds on climate contributes the largest uncertainty in predicting the future climate. Satellite observations provide an opportunity for learning about the behavior of clouds. This thesis seeks to assess the accuracy of cloud properties retrieved from multispectral...
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,...
This project, to propose an implementation strategy for standard monitoring
protocols, builds on my Pacific Northwest National Laboratory Fellowship to support a
study entitled Evaluating Cumulative Ecosystem Response to Restoration Projects in the
Columbia River Estuary (Diefenderfer et al. 2005). The major objective of the study was
to develop a...
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...
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...
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...
Coastal communities in the Pacific Northwest are looking for ways to increase the diversity of their economies in order to reduce the negative impacts of cyclic economic swings. The economic base of many coastal communities is directly tied to healthy, dynamic working waterfronts through fishing, recreation, tourism, ports, and allied...