A variety of stakeholders require information about marine systems. In the open ocean, pilots of marine vessels require knowledge about environmental conditions for safe passage and route planning. On the coastline, communities rely on information about nearshore dynamics to increase safety from coastal hazards such as nearshore pollutants, coastal erosion,...
The Large Wave Flume at the O.H. Hinsdale Wave Research Laboratory houses a piston wavemaker with a built-in active absorption system designed by MTS Systems Corporation. The performance of the active absorption system has not been properly assessed yet. This thesis evaluates the performance of the MTS active absorption system...
Currently, forecasts produced by the Oregon-Washington (OR-WA) Coastal Ocean Forecast System are constrained by assimilation of only surface observations. The 4-dimensional variational (4DVAR) data assimilation (DA) algorithm is utilized to combine the model and the data, with the time-independent forecast ("background'') error covariance B. In this study, two possible improvements...
Coastal communities in the U.S. Pacific Northwest (PNW) are rapidly engaging with the idea that hazards and environmental pressures are changing and may be characteristically different in the near future. This has led to a need for scientific knowledge and tools that can help coastal communities prepare and build resilience...
Coastal flooding and erosion are major concerns for low lying coastal communities -- particularly in light of accelerated sea level rise and climate change. To improve quantitative understanding of the physical drivers of both flooding and coastal landscape change, this dissertation explores coastal morphodynamics bridging the land-sea interface on modally...
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...
Sedimentary records from the North Atlantic, instrumental in the development of modern paleo-geomagnetic concepts, show a highly variable field even during times of constant polarity. Yet, our understanding of how the magnetization is acquired in the sediments is poorly understood. Primary magnetizations preserved in deep-sea sediments are known to be...
A wave-by-wave forecasting system is desired for optimization of wave energy conversion devices and for improving safety of vessel-based marine operations. This study outlines the first validation attempts of a recently developed forecasting system called Wavecast. The forecasting approach uses X-Band marine radar images for data assimilation, then reconstructs and...
Rip currents pose a serious danger to visitors of bathing beaches; they are also an important process in surf zone circulation. Haller et al. [2014] demonstrated that shore-based X-band radar can be used to compliment in situ measurements of rip currents. However, little is known of the underlying radar imaging...
Radiation stresses, defined as the excess flow of momentum due to the presence of waves (Longuet-Higgins, 1964), are the main drivers behind the cross-shore and longshore forcing that results in wave setup, set-down, and longshore currents (e.g. Svendsen, 2006). Longshore currents entrain and transport sediment and therefore play an important...
Field deployments, flume experiments, and a 2D wave model have been used to identify the characteristics of Clark-type oxygen microelectrodes and measurement parameters that could possibly bias eddy correlation (EC) flux measurements made under waves. Eddy correlation is a technique adapted from atmospheric sciences that couples concurrent and co-located velocity...
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...
Oregon State University conducted a series of laboratory experiments to measure and quantify the near-field wave effects caused within arrays of Wave Energy Converters (WEC). As the waves and WECs interact, the WECs generate radiated waves; these effects vary with the location within the array. Analyzing the near-field waves will...
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...
Coastal vegetation dampens waves which can provide benefits to the local area, but existing literature shows large variations in the degree of wave height attenuation depending on plant properties and wave conditions. Better knowledge of how to predict the wave height decay accurately in different types of vegetation may help...
This thesis investigates the effects of wave energy converters (WECs) on water waves through the analysis of extensive laboratory experiments, as well as subsequent numerical simulations. Data for the analysis was collected during the WEC-Array Experiments performed at the O.H. Hinsdale Wave Research Laboratory at Oregon State University, under co-operation...
Laboratory data of free surface elevations and fluid velocities were
obtained using a laser-Doppler velocimeter for the case of a periodic wave
plunging over an impermeable, steep (1:10) slope with a fixed bottom roughness.
The measurements were conducted over 15 cross-shore locations from the outer
surf zone to the swash...
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...
In the northwestern Gulf of Mexico there is a need for reliable water level forecasts to facilitate safe commercial navigation, marine construction, and emergency management. Though the low amplitude tides of the region can be predicted with conventional harmonic techniques, frequent strong storms make accurate forecasts of water levels difficult....
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...