EM 1110-2-1100 (Part II)
31 July 2003
Figure II-4-18. Field measurement of cross-shore flow on a barred profile (Duck, North Carolina,
October 1990)
(3) An alternate hypothesis for the generation of cell circulation is hydrodynamic instability (Hino 1974,
LeBlond and Tang 1974, Miller and Barcilon 1978). Instability models are based on small, periodic
perturbations in the setup and currents, with feedback between the currents and incident waves, to produce
regular patterns of nearshore circulation.
(4) Several generation mechanisms for rip currents and cell circulation have been proposed. On a given
beach, one or more of these mechanisms may drive the circulation pattern. Circulation patterns are dynamic,
changing spatially and temporally. Presently, there is no proven method to predict rip current generation or
the spacing between rips.
II-4-7. References
Baldock et al. 1998
Baldock, T. E., Holmes, P., Bunker, S., and Van Weert, P. 1998. "Cross-shore Hydrodynamics within an
Unsaturated Surf Zone," Coastal Engineering, 34, pp 173-196.
Battjes 1972
Battjes, J. A. 1972. "Set-up Due to Irregular Waves," Proceedings of the 13th Coastal Engineering
Conference, American Society of Civil Engineers, pp 1993-2004.
Battjes 1974
Battjes, J. A. 1974. "Surf Similarity," Proceedings of the 14th Coastal Engineering Conference, American
Society of Civil Engineers, pp 466-480.
Surf Zone Hydrodynamics
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