Flows Around Curves in Estuaries: Dynamics and Impacts

Oregon State University, Corvallis OR

Investigators

Abstract

Most estuaries have natural bends that flows must navigate around. Various studies have documented the circulation and stratification variability unique to flows of homogenous and stratified waters around bends in estuaries and rivers. However, none have attempted a systematic study in order to understand the dependence of the dynamics and impacts on a range of relevant estuarine parameters. This project will be a comprehensive study of the dynamics and regulation of flows (longitudinal and lateral) around channel bends in estuaries, the overall impact of these flows on salt transport, horizontal dispersion, and estuarine structure, and how this impact is dependent on estuarine regime. The project will engage a young audience through social media and science writing to convey the value of the physical ocean sciences. The training of a graduate research assistant and an undergraduate researcher in quantitative research is included. Several education and training opportunities for undergraduate and graduate students are planned. The project will additionally enhance collaborations and partnerships with scientists and stakeholders with interests in resource management and restoration of Yaquina Bay. Lateral (cross-channel) flows driven by a range of mechanisms (for example, differential advection, Coriolis forcing, asymmetric mixing, mixing over sloping bottoms) have been shown to interact strongly with the longitudinal estuarine currents, and have a fundamental impact on momentum budgets, dispersion of tracers and residence time in estuaries. This research would constitute the first systematic study of the dynamics of flows around curves in estuaries and will quantify the significance of these flows (relative to secondary flows driven by other mechanisms) and their impact on estuarine structure and function. The approach will include both idealized and realistic numerical simulations and analysis of previously collected data in estuaries that vary in channel size, curve structure and estuary regime classification. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.