A mechanism for sandbar straightening by oblique wave incidence

Breaker bars in the surf zone of sandy beaches generally evolve between straight bars parallel to the shore and meandering crescentic bars associated with intense (dangerous) currents flowing seaward through rip channels. Understanding the behavior of such systems is fundamental as they control the...

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Detalles Bibliográficos
Autores: Garnier, Roland, Falqués Serra, Albert|||0000-0002-3945-1509, Calvete Manrique, Daniel|||0000-0002-5402-5137, Thiebot, Jerome, Ribas Prats, Francesca|||0000-0003-4701-5982
Tipo de recurso: artículo
Fecha de publicación:2013
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/20100
Acceso en línea:https://hdl.handle.net/2117/20100
https://dx.doi.org/10.1002/grl.50464
Access Level:acceso abierto
Palabra clave:Morphology
Sand bars
Waves
rip channels
rip currents
morphological reset
morphodynamics
Sorra -- Bancs
Onades -- Influència
Àrees temàtiques de la UPC::Física
Descripción
Sumario:Breaker bars in the surf zone of sandy beaches generally evolve between straight bars parallel to the shore and meandering crescentic bars associated with intense (dangerous) currents flowing seaward through rip channels. Understanding the behavior of such systems is fundamental as they control the entire surf zone dynamics, the shape of the coastline, and the exchange of floating material with the shoreface. Although the mechanisms behind the meandering of an originally straight bar have been studied extensively, a clear physical explanation on the crescentic bar straightening was missing. Recent field observations have highlighted that this morphological reset can be due to wave obliquity. By using a two-dimensional horizontal morphological model, we show that the bar straightening by oblique waves occurs because the rip current is both weakened in intensity and shifted downdrift from the channel deepest section. The technique employed is useful for the study of other types of bed forms.