Abstract: Recent advances in understanding of sand movement in the surf zone provide a basis to discuss future directions of research. Problems exist in relating sediment flux and landform responses to waves, tides, and currents despite improved acquisition of data. Some gaps in knowledge are spatial and temporal processes that are geographic. NEARSHORE sediment transport has been a central research theme for coastal scientists. The result has been a dramatic increase in knowledge about surf-zone hydrodynamics. However, additional knowledge is needed to control development of all aspects of beach forms and to determine whether a beach will stabilize, erode, or accrete. Associated with these changes have been environmental regulations and coastal-engineering projects cost- ing more than one billion dollars annually. For most of the shoreline on the globe, data about quantities of sand input, output, and transport are incom- plete, and the relative contributions of longshore and shore-normal transport- beach morphology are unknown for many beaches. Two approaches are now used to predict nearshore sediment transport: (1) bulk transport models that evaluate the total amount of sediment flux in a surf zone based on either wave power or momentum transfer, and (2) instantaneous estimates of dispersal by a bottom shear-stress model that evaluates the fluid force balance at a specific site in a surf zone. Verification and refinement of these models have shifted recently from controlled lab- oratory situations to field experiments, many of which are large and expen- sive, multidisciplinary and interinstitutional such as the Nearshore Transport Study, the Canadian Coastal Sediment Study, and the U.S. Army Corps of Engineers' DUCK experiments. These studies have contributed analytical, empirical, technological, and methodological advances to understanding the dynamics of nearshore transport. The data are still being analyzed, but pre- liminary results indicate that many assumptions in simple models of sedi- ment transport may be inappropriate. Despite these advances, best estimates of nearshore sediment transport are now accurate only to an order of
Publication Year: 1988
Publication Date: 1988-04-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 17
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot