Collections > Electronic Theses and Dissertations > Dynamics and mixing in a microtidal, wind-driven estuary

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.