Barotropic tides in the South Atlantic Bight

Abstract

[1] The characteristics of the principal barotropic diurnal and semidiurnal tides are examined for the South Atlantic Bight (SAB) of the eastern United States coast. We combine recent observations from pressure gauges and ADCPs on fixed platforms and additional short-term deployments off the Georgia and South Carolina coasts together with National Ocean Service coastal tidal elevation harmonics. These data have shed light on the regional tidal propagation, particularly off the Georgia/South Carolina coast, which is perforated by a dense estuary/tidal inlet complex (ETIC). We have computed tidal solutions for the western North Atlantic Ocean on two model domains. One includes a first-order representation of the ETIC in the SAB, and the other does not include the ETIC. We find that the ETIC is highly dissipative and affects the regional energy balance of the semidiurnal tides. Nearshore, inner, and midshelf model skill at semidiurnal frequencies is sensitive to the inclusion of the ETIC. The numerical solution that includes the ETIC shows significantly improved skill compared to the solution that does not include the ETIC. For the M 2 constituent, the largest tidal frequency in the SAB, overall amplitude and phase error is reduced from 0.25 m to 0.03 m and 13.8°to 2.8°for coastal observation stations. Similar improvement is shown for midshelf stations. Diurnal tides are relatively unaffected by the ETIC.

Temperature correction and usefulness of ocean bottom pressure data from cabled seafloor observatories around Japan for analyses of tsunamis, ocean tides, and low-frequency geophysical phenomena

“…Seasonal variations of ocean tides have been reported in terms of sea level by a number of studies (e.g., Tamura, 1985;Pugh, 1987;Kang et al, 1995Kang et al, , 2002Leeuwenburgh et al, 1999;Blanton et al, 2004) and, in spite of limited studies, in terms of OBP (e.g., Tamura et al, 1986;Blanton et al, 2004). Tamura et al (1986) used the OBTM data of JMA (Isozaki et al, 1980) and pointed to a seasonal variation of the M 2 constituent, without detailed discussions.…”

“…Tamura et al (1986) used the OBTM data of JMA (Isozaki et al, 1980) and pointed to a seasonal variation of the M 2 constituent, without detailed discussions. Blanton et al (2004) used sea level and OBP data, and noted a seasonal variation of the M 2 constituent of the sea level, but hardly described the seasonal variation of the OBP tide because of the short duration of the observations. Although the effects of stratification (Kang et al, 2002) and tide-surge interaction (e.g., Pugh, 1987;Leeuwenburgh et al, 1999;Bernier and Thompson, 2007) have been suggested as causes of the seasonal variation of ocean tides in coastal regions, critical mechanisms have not yet been proposed (Woodworth, 2010).…”

Forced tidal response in the Gulf of Mexico

“…Blanton et al [2004] show that resolving these shallow regions improves the representation of the cross-shelf amplification as well as the phases for the semidiurnal tides in a model of the South Atlantic Bight. Similar coastal features are not well resolved in the GoM numerical model configuration used for this study, and this may lead to inaccuracies in the simulation of tidal dissipation.…”

“…[39] A study by Blanton et al [2004] also demonstrates the importance of resolving inlets and estuaries in a regional model for simulating tides. Blanton et al [2004] show that resolving these shallow regions improves the representation of the cross-shelf amplification as well as the phases for the semidiurnal tides in a model of the South Atlantic Bight.…”

An integrated ocean circulation, wave, atmosphere, and marine ecosystem prediction system for the South Atlantic Bight and Gulf of Mexico

“…In the shallowest part of the shelf, there is often a baroclinic southward current associated with a layer of fresh river water (Blanton et al 1989). The tides (predominantly M 2 ) have a range of 1-3 m along the coast, with tidal excursions of 4-20 km in the inner shelf off South Carolina and Georgia (Blanton et al 2004). Wind-driven currents lead to strong motions at 5-10-day periods.…”