Beach cusps and inner surf zone processesgrowth or destruction? A case study of Trafalgar Beach (Cádiz, Spain)

  1. Garnier, Roland
  2. Ortega Sánchez, Miguel
  3. Losada Rodríguez, Miguel Ángel
  4. Falqués, Albert
  5. Dodd, Nicholas
Revista:
Scientia Marina

ISSN: 0214-8358

Año de publicación: 2010

Volumen: 74

Número: 3

Páginas: 539-553

Tipo: Artículo

DOI: 10.3989/SCIMAR.2010.74N3539 DIALNET GOOGLE SCHOLAR lock_openAcceso abierto editor

Otras publicaciones en: Scientia Marina

Resumen

Large beach cusps (LBC, wavelength of ~ 30 m) are intertidal features that can alternately exist in the swash and in the inner surf zone due to tidal sea level changes. They have a larger cross-shore extent (up to 50 m) than traditional cusps. This extent has been explained by a shift of the swash zone during falling tide. The cusps immerse at rising tide and previous studies indicate that surf zone processes are exclusively destructive. Here, the behaviour of large beach cusps in the inner surf zone is investigated by using a 2DH morphological numerical model applied to Trafalgar Beach (Cádiz, Spain). The model results indicate that the inner surf zone processes do not always destroy the cusps but can in fact reinforce them by considering neither the swash processes nor the tidal changes. More generally, in conditions favouring the presence of the LBC the surf zone of a beach can be unstable, leading to the formation of transverse/oblique sand bars that can have characteristics similar to the LBC. Thus, in principle, the LBC could emerge not only due to swash zone morphodynamics but also due to surf zone morphodynamics or a combination of both.

Referencias bibliográficas

  • Aarninkhof, S. and R. Holman. – 1999. Argus video-based monitoring of the nearshore zone: a tool for both nearshore science and coastal zone management. Backscatter, 10(2): 8-11.
  • Almar, R., G. Coco, K. Bryan, D. Huntley, A. Short, and N. Senechal.– 2008. Video observations of beach cusp morphodynamics. Mar. Geol., 254: 216-223. doi:10.1016/j.margeo.2008.05.008
  • Booij, N., R.C. Ris and L.H. Holthuijsen. – 1999. A third-generation wave model for coastal regions: 1. Model description and validation. J. Geophys. Res., 104(C4): 7649-7666. doi:10.1029/98JC02622
  • Caballeria, M., G. Coco, A. Falqués and D.A. Huntley. – 2002. Self-organization mechanisms for the formation of nearshore crescentic and transverse sand bars. J. Fluid Mech., 465: 379-410. doi:10.1017/S002211200200112X
  • Calvete, D., N. Dodd, A. Falqués and S.M. van Leeuwen. – 2005. Morphological development of rip channel systems: Normal and near normal wave incidence. J. Geophys. Res., 110(C10006).
  • Castelle, B., P. Bonneton, H. Dupuis and N. Senechal. – 2007. Double bar beach dynamics on the high-energy meso-macrotidal french Aquitanian coast: a review. Mar. Geol., 245: 141-159. doi:10.1016/j.margeo.2007.06.001
  • Ciriano, Y., G. Coco, K. Bryan and S. Elgar. – 2005. Field observations of infragravity motions in the swash zone and beach cusp evolution. J. Geophys. Res., 110(C02018).
  • Coco, G., T. J. O’Hare, and D. A. Huntley. – 1999. Beach cusps: a comparison of data and theories for their formation. J. Coastal Res., 15(3): 741-749.
  • Coco, G., D.A. Huntley and T.J. O’Hare. – 2000. Investigation of a self-organization model for beach cusp formation and development. J. Geophys. Res., 105(C9): 21,991-22,002. doi:10.1029/2000JC900095
  • Coco, G., T.K. Burnet, B.T. Werner and S. Elgar. – 2003. Test of self-organization in beach cusp formation. J. Geophys. Res., 108(C33101).
  • Coco, G., T.K. Burnet, B.T. Werner and S. Elgar. – 2004. The role of tides in beach cusp development. J. Geophys. Res., 109(C04011).
  • Dodd, N., A. Stoker, D. Calvete and A. Sriariyawat. – 2008. On beach cusp formation. J. Fluid Mech., 597: 145-169. doi:10.1017/S002211200700972X
  • Falqués, A., G. Coco, and D. A. Huntley. – 2000. A mechanism for the generation of wave-driven rhythmic patterns in the surf zone. J. Geophys. Res., 105(C10): 24,071-24,088.
  • Garnier, R., D. Calvete, A. Falqués and M. Caballeria. – 2006. Generation and nonlinear evolution of shore-oblique/transverse sand bars. J. Fluid Mech., 567: 327-360. doi:10.1017/S0022112006002126
  • Garnier, R., D. Calvete, A. Falqués and N. Dodd. – 2008. Modelling the formation and the long-term behaviour of rip channel systems from the deformation of a longshore bar. J. Geophys. Res., 113(C07053).
  • Guza, R.T. and A. Bowen. – 1975 On the amplitude of beach cusps. J. Geophys. Res., 86: 4125-4131. doi:10.1029/JC086iC05p04125
  • Guza, R.T. and D. Inman. – 1975. Edge waves and beach cusps. J. Geophys. Res., 80(21): 2997-3012. doi:10.1029/JC080i021p02997
  • Holland, K.T. – 1998. Beach cusp formation and spacings at Duck, USA. Cont. Shelf Res., 18: 1081-1098. doi:10.1016/S0278-4343(98)00024-7
  • Holland, K.T. and R.A. Holman. – 1996. Field observations of beach cusps and swash motions. Mar. Geol., 134: 77-93. doi:10.1016/0025-3227(96)00025-4
  • Holland, K.T., R.A. Holman, T.C. Lippmann, J. Stanley and N. Plant. – 1997. Practical use of video imagery in nearshore oceanographic field studies. IEEE J. Ocean. Eng., 22(1): 81-92. doi:10.1109/48.557542
  • Holman, R.A. and J. Stanley. – 2007. The history and technical capabilities of Argus. Coastal Eng., 54(6-7): 477-491. doi:10.1016/j.coastaleng.2007.01.003
  • Inman, D.L. and R.T. Guza. – 1982. The origin of swash cusps on beaches. Mar. Geol., 49: 133-148. doi:10.1016/0025-3227(82)90033-0
  • Johnson, B. and J. Smith. – 2008. A two-scale approach to nearshore sediment transport modeling. In: J.M. Smith (ed.), Coastal Eng. 2008, pp. 1671-1683. World Sci., Singapore.
  • Masselink, G. and C.B. Pattiaratchi. – 1998. Morphological evolution of beach cusp morphology and associated swash circulation patterns. Mar. Geol., 146: 93-113. doi:10.1016/S0025-3227(97)00129-1
  • Masselink, G. and A.D. Short. – 1993. The effect of the tide range on beach morphodynamics: a conceptual model. J. Coastal Res., 9: 785-800.
  • Masselink, G., B.J. Hegge and C.B. Pattiaratchi. – 1997. Beach cusp morphodynamics. Earth Surf. Proc. Land., 22: 1139-1155. doi:10.1002/(SICI)1096-9837(199712)22:12<1139::AID-ESP766>3.0.CO;2-1
  • Masselink, G., P. Russell, G. Coco and D.A. Huntley. – 2004. Test of edge wave forcing during formation of rhyth- mic beach morphology. J. Geophys. Res., 109(C06003).
  • Ortega-Sánchez, M., M.A. Losada and A. Baquerizo. – 2003. On the development of large-scale features on a semi-reflective beach: Carchuna beach, southern Spain. Mar. Geol., 198: 209-223. doi:10.1016/S0025-3227(03)00126-9
  • Ortega-Sánchez, M., S. Fachin, F. Sancho and M.A. Losada. – 2008. Relation between beachface morphology and wave climate at Trafalgar beach (Cádiz, Spain). Geomorphology, 99: 171-185. doi:10.1016/j.geomorph.2007.10.013
  • Ribas, F., A. Falqués and A. Montoto. – 2003. Nearshore oblique sand bars. J. Geophys. Res., 108(C43119).
  • Short, A.D. – 1999. Handbook of Beach and Shoreface Morphodynamics. Wiley, Chichester.
  • Soulsby, R.L. – 1997. Dynamics of Marine Sands, Thomas Telford, London, U.K.
  • van Leeuwen, S.M., N. Dodd, D. Calvete and A. Falqués. – 2006. Physics of nearshore bed pattern formation under regular or random waves. J. Geophys. Res., 111(F01023).
  • Werner, B.T. and T.M. Fink. – 1993. Beach cusps as self-organized patterns, Science, 260: 968-971. doi:10.1126/science.260.5110.968 PMid:17818387
  • Wright, L.D. and A.D. Short. – 1984. Morphodynamic variability of surf zones and beaches: A synthesis. Mar. Geol., 56: 93-118. doi:10.1016/0025-3227(84)90008-2
Fuente de los datos: Dialnet