Dept. of Environmental and Biomolecular Systems
Oregon Health & Science University
Estuarine and coastal waters present complex physical systems, which support unique habitats, areas of high population density and growth, and large economic sectors (e.g. shipping, fishing, and tourism). Understanding the physical nature of these systems,including the circulation and transport, is necessary to guide management decisions which balance habitat, economic development, and urbanization. Numerical models present a means to simulate these systems under a wide array of realistic scenarios in an effort to fill knowledge gaps that may be cost prohibitive or impossible to fill via observations alone. Therefore, it is important that decisions inherent to model operation and the resulting outcome be properly assessed to ensure that the highest quality model results are available for managing agencies. This thesis presents modeling studies of two large river plume systems in the Pacific Northwest and southern British Columbia: the Columbia River and the Fraser River. Choices of the algorithm used to solve for the advection of salt and heat are investigated for each of these systems, while the choice of wind forcing is included for the Fraser River experiments. Assessment of the results for each experiment is provided in the context of retrospective observations. The modeling framework of a coastal margin observatory, CORIE [1, 5, and 6], developed with the study of the Columbia River in mind and the most current code, SELFE , used within this framework are utilized in these experiments and adapted from the Columbia River application to that of the Fraser River. Within SELFE, solution of the transport equations with an Upwind Method (UWM) is clearly shown to produce better plume salinities than an equivalent solution with an Eulerian-Lagrangian Method (ELM).
OGI School of Science and Engineering
Kilgren, Ryan Wesley, "Numerical simulations of large river plumes in the Pacific Northwest" (2006). Scholar Archive. 52.