My research focuses on the physical dynamics of estuarine and coastal systems. I study how currents and density fields respond to winds, surface heat flux, tides, and buoyant river inputs. Much of my research involves adapting hydrodynamic models to construct simulations and idealized process models. The realistic simulations are powerful tools for describing flow fields, diagnosing physical dynamics, and predicting circulation in coastal and estuarine waters. The idealized process models are well-suited to isolating forcing-response relationships and generalizing findings.

Coastal buoyant outflows
Rivers discharge fresh water into coastal waters. These buoyant outflows mix with ocean waters in estuaries and on the continental shelf. I am concerned with the transport and mixing of these coastal buoyant outflows. I am involved in ongoing research that investigates the behavior of the freshwater outflow from the Delaware Bay. Observations and simulation results indicate that the plume flows southward along the coast as a slender buoyancy current during light wind conditions. Strong southward (downwelling-favorable) winds accelerate the southward transport and push the buoyant waters against the coast. Strong northward (upwelling-favorable) winds can reverse the flow and transport buoyant waters northward, spread the plume offshore, and increase mixing with ocean waters. Tidal currents advect and mix buoyant waters within the estuary and on the continental shelf immediately outside the mouth.

Another research project investigates the transport of river waters discharged along the Oregon coast. Observations and simulation results indicate that the distribution of river waters and the nutrients they carry is controlled by the larger-scale wind-driven circulation along the continental shelf. During the predominant wintertime northward (downwelling-favorable) winds, nutrient-rich river waters are confined close to the coast by the coastal downwelling circulation. Intervals of southward (upwelling-favorable) winds are effective at transporting river waters across-shelf and can be important in seeding the continental shelf with nutrients.
The Connecticut River plume and the buoyant outflow from the Long Island Sound are two local examples of coastal buoyant outflows. I am interested in how these outflows are influenced by tides and winds. An important goal is to improve our understanding of the processes that control freshwater transport in this region.

Continental shelf circulation
I am involved in research that studies the mixing and transport of fresh water along the Middle Atlantic Bight. The goal is to identify the pathways that transport fresh water from the continental shelf to the deep ocean. This research will increase our understanding of shelf processes and improve the performance of global climate models.
I am studying the dynamics of wintertime circulation along the Oregon continental shelf. The circulation and density fields that develop during northward (downwelling-favorable) winds are of particular interest. I am interested in the development of instabilities in the downwelling jet. Another focus is on the behavior of this stratified flow in the vicinity of banks.

Long Island Sound
I have begun work on simulating circulation in the Long Island Sound. The Sound is an area of great commercial, recreational, and ecological interest. One objective is investigating the role physical dynamics play in the hypoxic conditions observed during the summer in the western Sound. Other research focuses include studying buoyancy-driven flow, tidal flow, wind-driven circulation, and air-sea interaction.

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