Dr. Peter Bacopoulos (Florida Department of Environmental Protection)

Title: Salinity in the lower St. Johns River: What is it and what drives it?

Host: Stephen Medeiros

Biography

Peter Bacopoulos, PhD, PE

• Coastal Engineer at Florida Department of Environmental Protection, since May 2017.
• Numerous affiliations, including ASCE, COPRI and Chi Epsilon.
• Floridian and UCF alumni, including conferred degrees in Civil Engineering at the BS, MS and PhD levels.
• Fun facts—UCF: (1) Mr. UCF 2000; and (2) UCF Orientation Team 2001.
• Three years of post-doctoral research at UCF. Four years as an Assistant Professor at the University of North Florida, including chairing three MS students.
• Total of 29 peer-reviewed journal articles, including 14 lead-authored. Service to the research community by having reviewed at least the same number of articles as published (>29).
• One vision is to develop a salinity modeling capability for the estuaries of the South Atlantic Bight, including the Cape Fear (NC), Cooper (SC), Savannah (GA) and St. Johns (FL) Rivers.
• Practically, the research provides information to coastal managers, municipalities and industry, ultimately affecting the public at large…civil engineering.

Abstract

Three main takeaways: (1) salinity in the river is well-mixed, where 3D/vertical variation is negligible and 2D/depth-integrated assessment is entirely justified; (2) tides, meteorology (remote more so than local) and freshwater inflows are important drivers of estuarine salinity; (3) salinity in the river is increasing nonuniformly due to sea-level rise.  As per takeaway #1, analysis of depth-variable measurements of salinity at numerous sites in the estuarine domain establishes the depth-uniformity and longitudinal variation of salinity.  As per takeaway #2, a large-scale numerical modeling approach with proper boundary of tides, winds and freshwater inflows accounts for the multitude of physical forcings driving longitudinal variations of salinity in the river.  As per takeaway #3, a multi-variate statistical approach with long-term (decade-plus) data of salinity, offshore water level and upstream freshwater inflow identifies statistically significant trends of salinity with respect to sea-level rise.

Related literature: Bacopoulos, P., Kubatko, E.J., Hagen, S.C., Cox, A.T., Mulamba, T., 2017. Modeling and data assessment of longitudinal salinity in a low-gradient estuarine river. Environmental Fluid Mechanics, doi: 10.1007/s10652-016-9486-8.