The role of tides in beach cusp development

View/ Open
Date
2004-04-10Author
Coco, Giovanni
Concept link
Burnet, Tom K.
Concept link
Werner, B. T.
Concept link
Elgar, Steve
Concept link
Metadata
Show full item recordCitable URI
https://hdl.handle.net/1912/3514As published
https://doi.org/10.1029/2003JC002154DOI
10.1029/2003JC002154Keyword
Beach cusp; Tides; Infiltration; Exfiltration; ErosionAbstract
Field measurements of morphology and swash flow during three episodes of beach cusp development indicate that tides modulate the height and cross-shore position of beach cusps. During rising tide, beach cusp height decreases as embayments accrete more than horns and the cross-shore extent of beach cusps decreases. During falling tide, beach cusp height increases as embayments erode more than horns and cross-shore extent increases. A numerical model for beach cusp formation based on self-organization, extended to include the effects of morphological smoothing seaward of the swash front and infiltration into the beach, reproduces the observed spacing, position, and tidal modulation. During rising tide, water particles simulating swash infiltrate, preferentially in embayments, causing enhanced deposition. During falling tide, exfiltration of water particles combined with diversion of swash from horns causes enhanced erosion in embayments. Smoothing of beach morphology in the swash zone seaward of the swash front and in the shallow surf zone accounts for most of the observed tidal modulation, even in the absence of infiltration and exfiltration. Despite the qualitative, and in some cases quantitative, agreement of the model and measurements, the model fails to reproduce observed large deviations of horn orientation from shore normal, some aspects of beach cusp shape, and deviations from the basic tidal modulation, possibly because of the simplified parameterization of cross-shore sediment transport and the neglect of the effects of sea surface gradients on flow.
Description
Author Posting. © American Geophysical Union, 2004. 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 109 (2004): C04011, doi:10.1029/2003JC002154.
Collections
Suggested Citation
Journal of Geophysical Research 109 (2004): C04011Related items
Showing items related by title, author, creator and subject.
-
Beach changes and management options for Nauset Barrier Beach and Orleans Town Beach, Cape Cod, MA : report to the Town of Orleans
Aubrey, David G.; Robertson, William (Woods Hole Oceanographic Institution, 1998-04)The present study investigated the shoreline and dune changes occurrng along Nauset Barrier Beach system during the past sixty years, based on examination of aerial photographs, charts, and other data sources. Significant ... -
Recent evolution of an active barrier beach complex : Popponesset Beach, Cape Cod, Massachusetts
Aubrey, David G.; Gaines, Arthur G. (Woods Hole Oceanographic Institution, 1982-01)Popponesset Spit, the barrier beach sheltering Popponesset Bay on Cape Cod, Massachusetts, has experienced large changes in its location and shape over the past thirty years. Concern by the public over loss of this ... -
Shifts in the microbial community composition of Gulf Coast beaches following beach oiling
Newton, Ryan J.; Huse, Susan M.; Morrison, Hilary G.; Peake, Colin S.; Sogin, Mitchell L.; McLellan, Sandra L. (Public Library of Science, 2013-09-10)Microorganisms associated with coastal sands serve as a natural biofilter, providing essential nutrient recycling in nearshore environments and acting to maintain coastal ecosystem health. Anthropogenic stressors often ...