Measurements of cross-shore flow were made across the surf zone during a storm as a nearshore bar became better developed and migrated offshore. Measured infragravity band spectra were compared to synthetic spectra calculated numerically over the natural barred profile assuming a white run-up spectrum of leaky mode or high-mode edge...
Time series of flow were measured across the inner surf zone during a storm. These data were used to quantify the dependence of wave height (transformed from measured flow) and velocity on local slope and depth. Similar to previous studies, as incident waves broke and propagated into the surf zone,...
The longshore variability of the coastal response to hurricanes may be examined within the framework of a storm-impact scaling model that compares spatially-variable beach morphology and fluid forcing. The relative elevations of dune height and storm-induced water levels are used to define three impact regimes (swash, collision, and overwash), within...
Wave setup and swash statistics were calculated from 154 runup time series steep beach under incident waves varying from 0.4 to 4.0 m significant wave height. incident wave height, setup, swash height, and total runup (the sum of setup and were found to vary linearly with the surf zone similarity...
Published June 1991. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Micropaleontological data have been analyzed through mathematical
and statistical procedures, in order to: (1) establish the distribution
pattern of radiolarian assemblages in the surface sediments,
(2) establish the relationship of these assemblages with oceanographic
variables, (3) determine the faunal composition down-core with
respect to the faunal surface pattern, and (4)...
The role of insect herbivores in the nutrient cycling dynamics of forest ecosystems remains poorly understood. Although past research in herbivory has focused primarily on the deleterious effects that insects can have on tree growth and mortality, the overall effects of herbivory are more complex. Herbivores have the potential to...
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....
The U.S. Pacific Northwest is home to one of the most extreme wave climates in the world with waves of 10 m in height arriving to the coast approximately each year. With an average water temperature of 12℃, the beaches in the region are too cold to go on a...
A new set of data from a large-scale sand bar migration experiment is presented. During this experiment, two sandbars were generated. One of the bar was generated by the action of undertow, and sediment moved offshore. The other bar was generated by the shoreward movement of sediment coming from the...
The Cocos Gap is a deeper portion, or saddle, of the Cocos
Ridge and forms part of the western boundary of the Panama Basing
It is probably typical of saddles within most submarine ridges, In
order to determine the mechanisms controlling sediment dispersal,
the nature and sources of the sediments...
The rip current field resulting from the transformation of surface gravity waves over offshore submarine canyons is studied. Employing a wave transformation model and a wave-induced circulation model over observed bathymetry we find that rip current circulation cells exist with alongshore spacing of O(1OOm) even though the nearshore bathymetry displayed...
This thesis contains a manuscript describing the implementation of a high resolution wave forecasting model for the coasts of Washington and Oregon. The purpose of this project was to advance the wave predictive capabilities of the states of Oregon and the southwest part of Washington by including the effects of...
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H. Tuba Özkan-Haller
This thesis contains a manuscript describing the implementation of a
A new technique for determining the amount of opal in deep-sea
sediments of any age is described. Using a normative calculation, a
portion of the analytical silica concentration of sediments is subtracted
as non-biogenic in proportion to the concentration of aluminum in the
sample. The ratio of SiO₂:Al₂O₃ used to...
The surf zone exhibits large energetic signals from wave shoaling and subsequent dissipation due to breaking, forcing circulation. The bathymetry responds to the wave and wave-induced circulation with the growth, transport, and destruction of large scale bathymetric features, such as mega ripples and sand bars. There is an obvious fluctuation...
Coastal flood hazard zones and the design of coastal defenses are often devised using either the maximum recorded total water level (TWL) or a 'design' event such as the 100-year return-level flood, usually projected from observed extreme events. Despite technological advances driving more consistent instrumental records of wave heights and...
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...
The rip current field resulting from the transformation of surface gravity waves over
offshore submarine canyons is studied. Employing a wave transformation model and a
wave-induced circulation model over observed bathymetry we find that wave height
variations associated with undulations in the canyon contours cause rip current circulation
cells with...
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...
Coastal and estuarine flooding and erosion events are usually driven by the cumulative effect of multiple individual processes like waves, streamflow, storm surge, and/or tides. This dissertation focuses on separating the influence of the regional and local-scale geomorphologic and hydrodynamic processes driving variability in the magnitude and impacts of extreme...
We present an optical method (optical current meter) to measure the longshore
component of nearshore surface currents by measuring the alongshore drift of persistent
sea foam in the surf zone. The method uses short time series of video data collected from
an alongshore array of pixels. These space-time data are...
We present an optical method (optical current meter) to measure the longshore
component of nearshore surface currents by measuring the alongshore drift of persistent
sea foam in the surf zone. The method uses short time series of video data collected from
an alongshore array of pixels. These space-time data are...
An operational inner-shelf wave forecasting system was implemented for the Oregon and southwest Washington coast in the U.S. Pacific Northwest (PNW). High-resolution wave forecasts are useful for navigational planning, identifying wave energy resources, providing information for site-specific coastal flood models, and having an informed recreational beach user group, among other...
Fluid-structure interaction (FSI) has been of significant research interest worldwide over the past several decades because of its variety of applications in both offshore and coastal engineering. Researchers analyzing FSI systems rely heavily on experimental tests in model scale in laboratories or large-scale sea trials. However, these tests are often...
The wave-induced velocity field in the nearshore is composed of contributions from incident wind waves (f > 0.05 Hz), surface infragravity waves (f < 0.05 Hz, lkl < (σ²/gβ) and shear waves (f < 0.05 Hz, lkl > σ²/gβ), where ƒ is the frequency, σ = 2πf, k is the...
Long-term research on freshwater ecosystems provides insights that can be difficult to obtain from other approaches. Widespread monitoring of ecologically relevant water-quality parameters spanning decades can facilitate important tests of ecological principles. Unique long-term data sets and analytical tools are increasingly available, allowing for powerful and synthetic analyses across sites....
A new remote sensing technique based on video image processing
has been developed for the estimation of nearshore bathymetry. The shoreward
propagation of waves is measured using pixel intensity time series collected at a
cross-shore array of locations using remotely operated video cameras. The incident
band is identified, and the...
A field experiment designed to test the hypothesis that infragravity and lower frequency waves influence the patterns of erosion and deposition on the beach foreshore has been carried out. The data show coherent fluctuations in the foreshore sediment level which can be related to low frequency wave motions. The fluctuations...
Femtosecond stimulated Raman spectroscopy (FSRS) is a powerful ultrafast technique which can track photoinduced excited state structural events on femtosecond (fs) to picosecond (ps) timescales. In addition to high temporal and spectral resolutions, FSRS provides a broad spectral window from ca. 100—2000 cm-1 for detection, enabling the direct mapping of...
Coastal foredunes protect lives, infrastructure, and ecosystems during severe winter storms. In the U.S. Pacific Northwest (PNW), coastal foredune geomorphology is determined by both physical and ecological mechanisms. Before the 1900's, the native plant Elymus mollis was the dominant dune grass and dune morphology was largely determined by sediment supply...
Beach response to overwash processes is a topic of significant importance. Two
particular aspects of this topic were chosen for detailed analysis: the distribution of
maximum wave runup elevations and the cross-beach celerity gradient of overwash bores
on natural beaches. Data were collected using both traditional nearshore instrumentation
and recently...
Simple parameterizations of dune erosion are necessary for forecasting erosion potential prior to an oncoming storm. Dune erosion may be parameterized in terms of the elevation of the total water level (composed of surge, tide, and wave runup) above the dune base and period of exposure of the dune to...
Coastal flood hazard zones and the design of coastal defenses are often devised using the maximum
recorded water level or a ‘‘design’’ event such as the 100 year return level, usually projected from
observed extremes. Despite technological advances driving more consistent instrumental records of waves
and water levels, the observational...
In this dissertation the interactions between hydrodynamics, sediment suspension and transport, and morphological evolution in the surf zone was investigated with a large-scale laboratory experiment data, CROss-Shore Sediment Transport Experiment (CROSSTEX). The data set included comprehensive measurements of water surface elevation, fluid velocity, sediment concentration, and morphology for irregular waves...
Video measurements of wave runup were collected during extreme storm conditions characterized by energetic long swells (peak period of 16.4 s and offshore height up to 6.4 m) impinging on steep foreshore beach slopes (0.05–0.08). These conditions induced highly dissipative and saturated conditions over the low-sloping surf zone while the...
Coastal dunes provide a diverse set of ecosystem services including coastal protection against destructive surge and waves during storm events. Dunes are constantly evolving through various stages of response to storm events and post-storm recovery at rates that vary due to a range of drivers including pre-existing morphology, environmental forcing...
The coast of Oregon is highly dynamic, with beach and dune morphodynamics constantly evolving in response to physical and ecological forcing at scales ranging from seconds to decades and meters to tens of kilometers. Evaluating spatial and temporal trends in shoreline evolution is paramount in understanding and eventually developing a...
The subaerial beach, composed of sand dunes and the foreshore, provides a natural buffer zone between vulnerable land and the dissipation of storm wave energy due to wave breaking. The natural beauty of this region is attractive to people, and as a result, significant investment has been placed in this...
This dissertation focuses on two core aspects of remote sensing: (a) interpretation of the remotely sensed data to identify and characterize sea surface features of interest, and (b) the quantitative analysis of previously characterized features to produce robust estimates of geophysical variables. Specifically, these aspects are addressed in the context...
Mapping out multidimensional potential energy surfaces has been a goal of
physical chemistry for decades in the quest to both predict and control chemical
reactivity. Recently a new spectroscopic approach called Femtosecond Stimulated Raman
Spectroscopy or FSRS was introduced that can structurally interrogate multiple
dimensions of a reactive potential energy...
Sandy beaches and dunes cover approximately one-third of the world’s ice-free coastlines and provide ecosystem services including coastal protection, recreation, wildlife habitat, and carbon sequestration. These dynamic interface habitats are variably shaped by wind, waves, sedimentary processes, and vegetation feedbacks. Positive biophysical feedbacks lead to the formation of vegetated coastal...
Documented and forecasted trends in rising sea levels and changes in storminess patterns have the potential to increase the frequency, magnitude, and spatial extent of coastal change hazards. To develop realistic adaptation strategies, coastal planners need information about coastal change hazards that recognizes the dynamic temporal and spatial scales of...
A technique is presented to remotely measure the scales and morphology of natural sandbars based
on the preferential dissipation of wind waves and swell over the crests of the bar. Photographic or
video images are recorded and statistical uncertainties associated with incident wave height modulations
removed by averaging (time exposures)....
Cartwright and Longuet-Higgins (1956) describe the statistical distribution of maxima that would result from the linear superposition of random, Gaussian waves. The distribution function depends solely upon the relative width of the power spectrum and root-mean-square value of the process time series. Runup field data from three experiments are presented...
The primary goal of this study is to look at the influence of family communication patterns on behavior and beliefs, specifically in the context of electoral behavior. In order to effectively influence potential voters and increase the likelihood that they intend to vote in federal elections in the long-term, we...
Coastlines have traditionally been engineered to maintain structural stability and to protect property from storm-related damage, but their ability to endure will be challenged over the next century. The use of vegetation to reduce erosion on ocean-facing mainland and barrier island shorelines – including the sand dunes and beaches on...
Understanding the past, present, and future behavior of our nation's shorelines is vital for sensible coastal management. Localized areas of erosion, termed "erosional hot spots", can shift the shoreline landward threatening coastal infrastructure (Kraus and Galgano, 2001; Stauble and Gravens, 2004; McNinch, 2004). One specific type of erosional hot spot...
The 14-km long Netarts Littoral Cell, located on the northern Oregon coast, experienced episodic erosion as a result of the severe 1997-98 El Nino and 1998-99 La Nina. The erosion events led to the development of a unique partnership bridging scientists, stakeholders, and various planning agencies. To address these erosion...
Chromosome segregation relies on coordinated activity of a large assembly of proteins, the kinetochore interaction network (KIN). How conserved the underlying mechanisms driving the epigenetic phenomenon of centromere and kinetochore assembly and maintenance are remains unclear, even though various eukaryotic models have been studied. More than 50 different proteins, many...
Full Text:
subcomplexes (Meraldi et al. 2006). In
metazoans five homologous complexes were identified
(CENP-C, CENP-H-I-K
Hazards threaten coastal communities and ecosystems over a wide range of spatiotemporal scales. One of the most pressing concerns for coastal property owners, decision makers, and researchers is the uncertain role that a changing climate will have on the intensity and frequency of these hazards. The significant uncertainties associated with...
To quantify the effect of wave breaking turbulence on sediment transport in the nearshore, the vertical distribution of time-averaged suspended sediment concentration (SSC) in the surf zone was parameterized in terms of the turbulent kinetic energy (TKE) at different cross-shore locations, including the bar crest, bar trough, and inner surf...
Oregon's estuaries are important ecosystems for scientific study. Consequently, knowledge of what research has been conducted helps us identify benchmarks and plan new projects. A comprehensive bibliography of published research, technical reports, local documents, and data sets is one means of recording this knowledge. For these reasons, the Guin Library...
Coastal communities throughout the US West Coast and elsewhere are facing the daunting task of preparing for climate change impacts, particularly the hazards from increased flooding and erosion. With sea-level rise, changing storminess patterns, and possible changes to the frequency and severity of major El Niño events, communities are already...
Steady flow fields and flow-induced wall stresses have been evaluated by experimental measurements and computational fluid dynamics (CFD) analysis in a series of patient-specific abdominal aortic aneurysm (AAA) models, over a range of Reynolds numbers (Re) from 125 to 3000 (500 to 3000 for CFD). Experimental methods used particle image...
The phragmoplast associated kinesin, PAKRP2, from the model organism Arabidopsis thaliana is categorized as an orphan, or ungrouped, kinesin due to structural divergences from the established 14 kinesin families. An early study on PAKRP2 found that it localized to the phragmoplast mid zone during the late stages of cell division...
In this study, we have characterized a series of patient Abdominal Aortic
Aneurysms (AAAs) based on their geometric parameters, wall pressure
distributions and ages. Abdominal aortic aneurysms (AAAs) are localized aortic
dilations that have been estimated to occur in 5 to 7 percent of the U.S. population
over age 60....
The use of remote sensing techniques in coastal science and engineering has rapidly increased in the past few decades. This dissertation outlines new remote sensing tools using two remote sensing technologies (lidar and X-band marine radar) along with two nearshore hydrodynamic and morphodynamic analyses supported or motivated by these remote...
A nonlinear model is developed to study the time‐dependent relationship between the alongshore variability of a sandbar, a(t), and alongshore‐averaged sandbar position, xc(t). Sediment transport equations are derived from energetics‐based formulations. A link between this continuous physical representation and a parametric form describing the migration of sandbars of constant shape...
Paraprofessional counselors comprise a significant sector of the mental health workforce (Buchbinder, 2003; Golden, 1991; Nieuwsma et al., 2014; Norcross, 2000). Professional counselors have offered both praise (Durlak, 1979) and criticism (Nietzel & Fisher, 1981) for paraprofessional counselors and the services that they provide. Paraprofessional counselors work under the guidance...
Managing multiple ecosystem services (ESs) across landscapes presents a central challenge for ecosystem-based management, because services often exhibit spatiotemporal variation and weak associations with co-occurring ESs. Further focus on the mechanistic relationships among ESs and their underlying biophysical processes provides greater insight into the causes of variation and covariation among...
Cell division, arguably the most important event during the life cycle of the eukaryotic cell, is achieved through a complicated yet beautiful machinery. The mitotic spindle — a microtubule-based bipolar structure—is the cellular machinery responsible for the correct segregation of the genetic material, chromosomes. The protein-based nanomachines termed molecular motors...
Documented trends in rising sea levels, storminess, and extreme wave heights have the potential to increase the frequency and magnitude of coastal change hazards, increasing risks to coastal infrastructure and environmental resources. Coastal planners and decision makers need information about the impacts of future hazards in order to apply mitigation...
Swash zone processes are of significant importance to foreshore morphologic change. This thesis addresses the importance of the uprush and backwash fluid motions and flow duration effects to the resulting sediment transport. The analysis relates the field observations to well known sediment transport formulations as well as investigates the importance...
Estuaries represent the confluence of land and ocean environments and encompass a number of complex interactions amongst tides, winds, offshore waves and the riverine contributions, all of which contribute to total water levels (TWLs). The study of TWLs and the relative weight of its components can assist local communities in...
Coastal hazards are the result of numerous physical processes cumulatively causing water levels to flood and erode the land. The waves, storm surges, tides, and run-off contributing to elevated water levels are each the product of chaotic and random weather patterns. These stochastic weather patterns dissipate energy in Earth's climate...
Total water levels (TWLs) within estuaries are influenced by tides, wind, offshore waves, and streamflow, all of which are uniquely affected by climate change. The magnitude of TWL associated with various return periods is relevant to understanding how the hydrodynamics of a bay or estuary may evolve under distinct climate...
Nature of the Phenomenon
The primary purpose of this investigation was to determine if the
predisposition of counselor candidates on selected factors found to be
associated with effective counseling, upon entering a counselor education
program, was predictive of effective counselors at the end of that
program.
Hypotheses
Two central hypotheses...
Vegetation can protect communities by reducing nearshore wave height and altering sediment transport processes. However, quantitative approaches for evaluating the coastal protection services, or benefits, supplied by vegetation to people in a wide range of coastal environments are lacking. To begin to fill this knowledge gap, we propose an integrated...
An estimated total of 30.3 million people have diabetes in the United States, a disease characterized by chronic elevation in blood glucose which over time, can lead to a host of health problems. Currently the most common types of diabetes are type 1, type 2, and gestational. The principal hormone...
Pharmacy technicians play a critical role in delivering patient care. As part of their regular job roles, however, these individuals spend time walking on the campuses of the healthcare facilities at which they work. This walking or ‘move-time’ is considered nonvalue-added time and constitutes a cost for the organization.
To...
A physical model study was performed to examine the forces and response of 1:6 scale wood-frame coastal residential structures subjected to storm surge and waves. An on-grade and an elevated specimen were tested and exposed to regular waves with varying water depths and wave heights to simulate Hurricane Sandy’s conditions....
As the aging population continues to grow worldwide, age-related complications are becoming more apparent within the aging population. One of the first age-related complications to become apparent is age-associated memory impairment and it can make the elderly more dependent on caregivers early on. The N-methyl-D-aspartate (NMDA) receptor is important to...
Natural habitats have the ability to protect coastal communities against the impacts of waves and storms, yet it is unclear how different habitats complement each other to reduce those impacts. Here, we investigate the individual and combined coastal protection services supplied by live corals on reefs, seagrass meadows, and mangrove...
In the future, Earth will be warmer, precipitation events will be more extreme, global mean sea level will rise, and many arid and semiarid regions will be drier. Human modifications of landscapes will also occur at an accelerated rate as developed areas increase in size and population density. We now...
Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with...
Oregon Biography Index is intended to serve primarily as a starting point in locating biographies of Oregonians. We have indexed 47 historical volumes which are either entirely devoted to biographies or have large self-contained biographical sections. The profiles in the books vary widely in accuracy and detail. Birth dates of...
Purpose of the Study
The purpose of the study was to determine whether there were
significant differences in students' career maturity as a result of
exposure to the concepts of career education. The study evaluated the
relative effectiveness of a developing comprehensive career education
project to help students attain increased...
Published January 1957. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Biological invasions and climate change represent two preeminent threats to ecological communities and biodiversity, altering the distribution and abundance of species, disrupting existing species interactions and forming unprecedented ones, and creating novel ecological communities. Many of the most successful invasive species are also ecosystem engineers, species that physically modify the...