Tidal and subtidal hydrodynamics over ridge-swale bathymetry

Abstract Observations along two inner shelf transects of East-Central Florida provide information on the influence of ridge-swale bathymetry on tidal and subtidal hydrodynamics and the applicability of open channel flow theory in an area of complex bathymetry. Results from vessel-based ADCP measurements were compared to two analytical models that yield tidal and subtidal solutions. Of the two transects investigated, the northern transect, which has a relatively smooth bathymetry and a gentle bottom slope (0.002), exhibited tidal hydrodynamics that were more influenced by local acceleration than by frictional effects. Subtidal hydrodynamics at the northern transect were influenced by Coriolis (geostrophy) or by advection (Bernoulli-type dynamics). The south transect crossed a more prominent swale, with a steeper bottom slope (0.006). Frictional effects dominated the south transect as the flow maximum was located over the deepest part of the transect. Results obtained with both the tidal and subtidal analytical model solutions highlight the influence of ridge-swale bathymetry in inner shelves at those temporal scales. Analyses indicate whether open channel concepts are applicable to inner shelf dynamics.