Tidal and meteorological forcing of sediment transport in tributary mudflat channels
MetadataShow full item record
KeywordSediment transport; Intertidal sedimentation; Salinity gradients; Tidal inlets; Topographic effects; San Francisco Bay, California, USA
Field observations of flow and sediment transport in a tributary channel through intertidal mudflats indicate that suspended sediment was closely linked to advection and dispersion of a tidal salinity front. During calm weather when tidal forcing was dominant, high concentrations of suspended sediment advected up the mudflat channel in the narrow region between salty water from San Francisco Bay and much fresher runoff from the small local watershed. Salinity and suspended sediment dispersed at similar rates through each tidal inundation, such that during receding ebbs the sediment pulse had spread spatially and maximum concentrations had decreased. Net sediment transport was moderately onshore during the calm weather, as asymmetries in stratification due to tidal straining of the salinity front enhanced deposition, particularly during weaker neap tidal forcing. Sediment transport by tidal forcing was periodically altered by winter storms. During storms, strong winds from the south generated wind waves and temporarily increased suspended sediment concentrations. Increased discharge down the tributary channels due to precipitation had more lasting impact on sediment transport, supplying both buoyancy and fine sediment to the system. Net sediment transport depended on the balance between calm weather tidal forcing and perturbations by episodic storms. Net transport in the tributary channel was generally off-shore during storms and during calm weather spring tides, and on-shore during calm weather neap tides.
Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 27 (2007): 1510-1527, doi:10.1016/j.csr.2007.01.010.
Showing items related by title, author, creator and subject.
Ralston, David K.; Geyer, W. Rockwell; Traykovski, Peter A.; Nidzieko, Nicholas J. (2012-01-25)Tidal flats at a river mouth feature estuarine and fluvial processes that distinguish them from tidal flats without river discharge. We combine field observations and a numerical model to investigate hydrodynamics and ...
Aubrey, David G.; Speer, Paul E. (Woods Hole Oceanographic Institution, 1983-06)Various aspects of sediment transport in and around natural, unstructured tidal inlets were investigated over the two year period of study. Concentrating on two tidal inlets (Nauset Inlet and Popponesset Inlet, Cape Cod, ...
Tidal asymmetry and residual circulation over linear sandbanks and their implication on sediment transport : a process-oriented numerical study Sanay, Rosario; Voulgaris, George; Warner, John C. (American Geophysical Union, 2007-12-22)A series of process-oriented numerical simulations is carried out in order to evaluate the relative role of locally generated residual flow and overtides on net sediment transport over linear sandbanks. The idealized ...