Collaborative Research: Asymmetric Circulation in Wind-Driven Bays

University Of Florida, Gainesville FL

Investigators

Abstract

ABSTRACT OCE-0425147 Asymmetric circulation in wind-driven bays Intellectual Merit A recent analytical model predicts that the wind-driven circulation in small coastal basins is fundamentally influenced by the Earth's rotation when the basin depth is greater than the Ekman depth. Rotation affects the character and complexity of fluid parcel trajectories, with important consequences for mixing and residence times. A combination of observations and analytical and numerical simulations will be conducted to verify and extend this model. Field observations will be done during the winter season 2004-2005 in Bahia Concepcion, on the Gulf of California side of the Baja California peninsula in Mexico. The bay is subject to strong wind forcing throughout the winter, when it is vertically well mixed. The observations will include moored instrumentation, shipboard surveys and drifter deployments and the scientific objectives are: (a) to describe through observations how rotation affects the wind-driven circulation and the exchange with the ocean in a relatively deep, well-mixed, semi-enclosed bay that is exposed to strong winds, and (b) to extend the analytical model to represent the circulation driven by tides and by lateral density gradients, and to describe with numerical models how advection and vertical stratification modify this circulation. Broader Impacts The ecological and societal importance of small coastal basins (bays, estuaries, lagoons) is out of proportion with their size. Among other ecological functions, lagoons and estuaries serve as way stations for bird migration, as nurseries for fauna and flora and as mating and calving grounds for certain marine mammals. At the same time these water bodies have been deeply impacted by anthropogenic activities. By developing a dynamical description of the processes that control circulation in these basins and exchange with the ocean, this study will help minimize human impacts such as sewage discharge through science-based management and engineering practices. In addition, this project represents international collaboration with Mexican scientists, supports two graduate students. One of the PIs is a member of an underrepresented group. The study will also expose undergraduates, including minority groups, to research.