Observations of Currents and Bedforms in a Tidally Modulated Inlet

Tom Lippmann and Lindsay McKenna


Friday, Apr. 6, 2012, 3:00pm
Chase 130

Bedforms ranging in size from sand ripples to sand waves are common dynamic features in sandy bottom inlets and harbors.  Their characteristics, orientation, and migration define the nature of the sediment transport driven by waves and currents within the inlet, often dominated by tidal flows.  In turn, the presence of bedforms – with varying magnitudes in height and wavelength – modifies the seafloor roughness and bottom boundary layer processes that feed back into the nature of the flow field, particularly in the vertical structure of the horizontal currents.  In the Fall of 2011, a pilot field experiment was conducted in the tidally modulated inlet leading to Hampton/Seabrook Harbor, NH, to coincidentally observe the fine scale seafloor topographic evolution and the mean flow fields.   Observations of bedforms and mean currents were obtained over a 4 week period with a combination of periodic multibeam echosounder (MBES) surveys, shipboard acoustic Doppler current profiles (ADCP), and moored ADCP observations.  Preliminary results from the Hampton Inlet Experiment will be presented.  Additionally, a pre-view of our research plans for additional field work this spring at New River Inlet, NC will be discussed. 


Tom Lippmann is a nearshore oceanographer with affiliation with the Department of Earth Sciences and the Ocean Engineering program.

He received a BA in Mathematics and Biology from Linfield College (1985), and an MS (1989) and PhD (1992) in Oceanography at Oregon State University. His dissertation research conducted within the Geological Oceanography Department was on shallow water physical oceanography and large scale coastal behavior. He went on to do a Post Doc at the Naval Postgraduate School (1992-1995) in Physical Oceanography.

He worked as a Research Oceanographer at Scripps Institution of Oceanography (1995-1999) in the Center for Coastal Studies, and retains a research associate with the Integrated Oceanography Division at SIO. He was then a Research Scientist at Ohio State University (1999-2008) jointly in the Byrd Polar Research Center and the Department of Civil and Environmental Engineering and Geodetic Science.

Dr. Lippmann's research is focused on shallow water oceanography, hydrography, and bathymetric evolution in coastal waters spanning inner continental shelf, surf zone, and inlet environments. Research questions are collaboratively addressed with a combination of experimental, theoretical, and numerical approaches. He has participated in 14 nearshore field experiments and spent over 18 months in the field.


Lindsay McKenna is pursuing an M.S. in Earth Sciences: Mapping Option. Lindsay graduated with a B.S. in Geological Sciences from Brown University in 2007. She completed her senior thesis on “Coastal Dynamics of Annawamscutt Beach.” Before coming to CCOM, Lindsay worked as a geologist at an environmental consulting firm in the NYC metro area. Lindsay is an active member of the Surfrider Foundation and enjoys training for triathlons.