Influence of winter waves on the longitudinal growth of the Punta Banda Estuary sandbar, Todos Santos Bay, Baja California, Mexico

Punta Banda Estuary, located within Todos Santos Bay, on the northwest coast of the Baja California Peninsula, is separatedfrom the bay by a single sandbar, approximately 8 km long. From 1972 to 2003 this sandbar showed a longitudinal net growth of420 m, which decreased the width of the estuary mout...

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Detalles Bibliográficos
Autores: O Delgado-González, L Galindo-Bect, CR Torres-Navarrete, R Cano-Cetina, A Martínez-Díaz-de-León, R Lizárraga-Arciniega, R Blanco-Betancourt, E Gil-Silva
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:México
Institución:Universidad Autónoma de Baja California
Repositorio:Redalyc-UABC
OAI Identifier:oai:redalyc.org:48034106
Acceso en línea:https://www.redalyc.org/articulo.oa?id=48034106
Access Level:acceso abierto
Palabra clave:Ciencias de la Tierra
refracción
oleaje invernal
Estero de Punta Banda
transporte de sedimento
Descripción
Sumario:Punta Banda Estuary, located within Todos Santos Bay, on the northwest coast of the Baja California Peninsula, is separatedfrom the bay by a single sandbar, approximately 8 km long. From 1972 to 2003 this sandbar showed a longitudinal net growth of420 m, which decreased the width of the estuary mouth by more than 400 m. Despite the bar’s rapid growth it has beensuggested that the estuary mouth remains open because in spring, summer and autumn the longshore sand transport isnortheastward, but during winter the longshore sand transport should be toward the southwest, away from the mouth,establishing a balance between the amount of sediment transported both ways. In this study we analyze wave data acquired fromNovember 2004 to March 2005 on the bay side of the sandbar, and for the first time provide the magnitude and direction of thelongshore sand transport during winter. The results show that during this season the dominant waves approach the bay from thewest-northwest and the sandbar from the west, inducing a net longshore sand transport of 817 m3 day–1 to the northeast. Thisresult contradicts the hypothesis of a longshore sand transport balance, and shows that throughout a typical year the netlongshore sand transport is to the northeast. The fact that the estuary mouth has not closed up should be attributed to othercauses, such as extraordinary amounts of rain during the rainy season or inequalities between the ebb and flood tidal currentvelocities to the estuary.