The vertical propagation of Coastal Trapped Waves (CTWs) due to subsurface ridges is explored with the help of linear numerical and analytical models. Results show that submerged ridges projecting from the shoreline can scatter a horizontally propagating single baroclinic mode Kelvin wave into both upward and downward propagating Kelvin wave...
A carefully calibrated primitive-equation model from 41°N to 48°N is used to study the poleward undercurrent off the US west coast. Chapter 2 describes poleward flow over the slope from Eulerian and Lagrangian perspectives. The model is robust, in the sense of several characteristics being qualitatively consistent with observational and...
This dissertation is concerned with the behavior of sulfur in intermediate-silicic arc magmas associated with subduction at convergent margins. In particular it focusses on oxidized, sulfur-rich magmas, the conditions at which they might reach sulfate saturation, and implications of sulfate saturation. It is divided into an investigation of natural samples...
Biogeochemical mechanisms employed by key organisms, or symbiotic associations of organisms, transform the function and structure of their environment through processes recognized as ecosystem engineering. This dissertation seeks to investigate organism-ecosystem interactions that serve globally significant ecological functions in marine systems and impact how systems respond to environmental change. Using...
With the increasing international focus on transboundary cooperation as a part of the Sustainable Development Goal (SDG) Framework, there is global recognition of transboundary water cooperation as a tool for improved governance and management of transboundary surface and groundwaters. Yet, there is not an agreed upon definition of transboundary water...
By inverting EarthScope long-period magnetotelluric (MT) data from the southeastern United States (SEUS), we obtain electrical conductivity images that provides key insights into the geodynamics of this region. Significantly, we resolve a highly electrically resistive block that extends to mantle depths beneath the modern Piedmont and Coastal Plain physiographic provinces....
Forests play an integral role in the global carbon cycle, regulating the atmospheric CO₂ concentration by sequestering nearly one third of anthropogenic carbon emissions and storing carbon for centuries. Forest ecosystems are integrated into the culture, ecology, and economy of western North America, supporting wildlife habitat, local economies, recreation, and...
The Global Overturning Circulation (GOC) is a major component of the global climate system. Understanding its behavior is pertinent to our prediction of climate change in the future. The lack of long-term observations of GOC in the modern instrumental era necessitates studies of GOC using paleoceanographic records. Of great interest...
New ice cores retrieved from the Taylor Glacier (Antarctica) blue ice area contain ice and air spanning the Marine Isotope Stage (MIS) 5/4 transition, a period of global cooling and ice sheet expansion. Chronologies were determined for the ice and air bubbles in the new ice cores by visually matching...
Reconstructing the sensitivity of past climate to forcings, and of ancient glaciers and ice sheets to this climate, can allow us to better understand the range of climate and cryosphere behavior we may see in the coming centuries. The Arctic is a region of particular importance due to its well-documented...
The objective of this dissertation was to understand the physical mechanisms affecting inversion events in a complex forested mountain landscape. This work was motivated by the long-term studies of climate at the Andrews Forest, short-term studies of vertical temperature, light, wind, and moisture gradient in old-growth trees, and interest in...
Large igneous provinces (LIPs) and intraplate seamounts reflect of anomalous mantle melting and illuminate interior processes of the Earth. These features are in all ocean basins and show the mantle’s evolution over time, then can provide information on plate tectonic processes, such as plate motion over time, spreading ridge formation,...
Magnetotellurics is used in two geologic settings on scales ranging from 1000-km tectonic structures to local features hundreds of meters wide. These areas are the Midcontinent Rift System (MRS) and its related mantle plume in the northern Midwestern United States and Newberry Volcano in central Oregon.
The MRS study uses...
The focus of this dissertation is the analysis of submesoscale and finescale features measured at oceanic fronts and the role they play in the transport of heat and salt. Two different geographical areas were used to analyze this transport: one, an area on the western side of the North Atlantic...
Many marine bivalves are sensitive to ocean acidification (OA) stress and often show heightened sensitivity during brief early larval and post-larval life stages, potentially leading to population bottlenecks. Most of the evidence to date has been collected in laboratory experiments that focused on physiological responses at the organismal level under...
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...
The variability of coastal carbonate chemistry continues to provide significant hurdles for understanding interactions between anthropogenic and natural CO2 cycling and resultant effects on coastal acidification dynamics. Attribution of the anthropogenic component is vital for identifying the impacts of increasing atmospheric carbon on coastal habitats such as coral reefs, upwelling...
Numerous studies have explored how alluvial channel size and morphology are adjusted to different sediment and flow conditions, yet we still know very little about how and to what degree the flow regime controls channel form and processes. We use the term ‘channel form’ to refer to the size and...
Internal waves and tides are a dominant source of current variability, and they are intermittent and hard to predict. Internal waves can have significant variability in alongshore structure. However, previous studies on internal waves have focused primarily on their cross-shore structure and propagation. For example, while alongshore-propagating superinertial internal tides...
Small rivers, such as those that line the Oregon coast, have been shown to deliver significant concentrations of suspended sediments and nutrients to estuaries and the coastal ocean during wet seasons during which winds are predominantly downwelling-favorable. The fate of the buoyant source water and of any suspended or dissolved...