Wind-Driven Circulation in a Shallow Microtidal Estuary: The Indian River Lagoon

Studying wind-driven fluctuations in the surface elevation along the Indian River Lagoon (IRL) allows researchers to better understand the best methods for managing sustainable water quality in a microtidal estuary. Water quality has a direct effect not only on the marine life, but also on tourism. This study improves the knowledge of circulation and surge in a shallow, microtidal estuary while enabling validation of numerical modeling efforts. Two submersible pressure sensors were deployed in the IRL for 7 months. Data collected from these gauges is analyzed in conjunction with data from permanent gauges at Haulover Canal and Sebastian Inlet, with an emphasis placed on the relationship between surface elevation and meteorological forcing. A time series analysis was employed to correlate periods of harmonic oscillations with wind events. Analysis focused on the direction of the wind with respect to the along-estuary and cross estuary orientation of the lagoon. Results indicate that the water rises or falls uniformly in the cross-estuary direction and is transported to the south during Nor'easter events, piling up at the constriction south of Sebastian Inlet. Study results will be used to provide a better understanding of circulation in shallow-water estuaries, as well as improve numerical models to better predict wind-driven circulation in the IRL.