COMPARATIVE MORPHODYNAMICS BETWEEN EXPOSED AND REEF PROTECTED BEACHES UNDER HURRRICANE CONDITIONS

[摘要] It has been widely documented that coral reefs play a very important role in the dissipation of wave energy. Observations of beach morphology, made before and after a major hurricane that hit SE Mexico in October 2005 (Wilma), show widespread erosion at an exposed beach (Cancun), but unexpected beach accretion 25 km south at a beach fronted by a fringing reef (Puerto Morelos). The DELFT 3D morphodynamic model is used at a regional scale to explain the divergent morphological behavior of both beaches and explore the processes involved at both sites. A combination of offshore transport at the exposed beach, large scale southward sediment transport and onshore transport along the reef protected beaches seems to be the main explanation for the observed morphological behavior. Dune erosion and beach face sand relocation are also partially responsible for the beach progradation at the reef protected site.

[学科分类] 建筑学

[关键词] coral reefs;hurricanes;sediment transport