Collections > Electronic Theses and Dissertations > Dynamics and mixing in a microtidal, wind-driven estuary
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In estuaries, tides are considered to be the dominant mechanism driving the mixing of freshwater from rivers with the saline waters from the adjoining ocean, hence determining the along-estuary salinity gradient and strength of estuarine circulation. However, there are a number of microtidal estuaries, driven primarily by the wind and not tides. These estuaries are prone to human-induced water quality problems, as the episodic nature of wind leads to less vertical mixing and strong stratification, which when combined with eutrophication results in bottom-water hypoxia. This dissertation research aims to further our understanding of the dynamics and mixing in these wind-driven estuaries. Through field measurements collected in the Neuse River Estuary in 2013 and 2016, we first investigate the along-channel momentum and salt budgets to determine the primary balances in a wind driven estuary. Then we define a new set of mixing parameters to compare it to classical tidal estuaries. Finally, we characterize the nature and efficiency of turbulent mixing produced in the Neuse.