Effects of locally generated wind waves on the momentum budget and subtidal exchange in a coastal plain estuary
Pareja‐Roman, L. Fernando
Chant, Robert J.
Ralston, David K.
MetadataShow full item record
A numerical model with a vortex force formalism is used to study the role of wind waves in the momentum budget and subtidal exchange of a shallow coastal plain estuary, Delaware Bay. Wave height and age in the bay have a spatial distribution that is controlled by bathymetry and fetch, with implications for the surface drag coefficient in young, underdeveloped seas. Inclusion of waves in the model leads to increases in the surface drag coefficient by up to 30% with respect to parameterizations in which surface drag is only a function of wind speed, in agreement with recent observations of air‐sea fluxes in estuaries. The model was modified to prevent whitecapping wave dissipation from generating breaking forces since that contribution is integrally equivalent to the wind stress. The proposed adjustment is consistent with previous studies of wave‐induced nearshore currents and with additional parameterizations for breaking forces in the model. The mean momentum balance during a simulated wind event was mainly between the pressure gradient force and surface stress, with negligible contributions by vortex, wave breaking (i.e., depth‐induced), and Stokes‐Coriolis forces. Modeled scenarios with realistic Delaware bathymetry suggest that the subtidal bay‐ocean exchange at storm time scales is sensitive to wave‐induced surface drag coefficient, wind direction, and mass transport due to the Stokes drift. Results herein are applicable to shallow coastal systems where the typical wave field is young (i.e., wind seas) and modulated by bathymetry.
Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research-Oceans 124(2), (2019):1005-1028, doi:10.1029/2018JC014585.
Suggested CitationPareja-Roman, L. F., Chant, R. J., & Ralston, D. K. (2019). Effects of locally generated wind waves on the momentum budget and subtidal exchange in a coastal plain estuary. Journal of Geophysical Research-Oceans, 124(2), 1005-1028.
Showing items related by title, author, creator and subject.
MacMahan, Jamie; van de Kreeke, Jacobus; Reniers, Ad; Elgar, Steve; Raubenheimer, Britt; Thornton, Ed B.; Weltmer, Micah; Rynne, Patrick; Brown, Jenna (Elsevier, 2014-04-12)Amplitudes of semi-diurnal tidal fluctuations measured at an ocean inlet system decay nearly linearly by 87% between the ocean edge of the offshore ebb-tidal delta and the backbay. A monochromatic, dynamical model for a ...
Wargula, Anna E.; Raubenheimer, Britt; Elgar, Steve (John Wiley & Sons, 2014-05-20)Observations of waves, flows, and water levels collected for a month in and near a long, narrow, shallow (∼ 3000 m long, 1000 m wide, and 5 m deep), well-mixed ocean inlet are used to evaluate the subtidal (periods > 30 ...
Subtidal current structure and variability of the continental shelf and slope of the northern South China Sea Tai, Jen-Hua; Yang, Kai-Chieh; Gawarkiewicz, Glen G. (Terrestrial, Atmospheric and Oceanic Sciences, 2017-06)The spatial structures and temporal variations in subtidal currents in the northern South China Sea (SCS) are quantified in this study using 20-day to 9-month measurements from eight acoustic Doppler current profiler ...