Infragravity Energy and Its Implications in Nearshore Sediment Transport and Sandbar Dynamics. Revision.

摘要

This report presents a tutorial on infragravity motions in the nearshore zone with particular attention given to the influence of infragravity motions on sediment transport and runup. This ubiquitous low-frequency wave motion, with periods from 30 sec to several minutes, often contributes a substantial portion to the surf zone energy especially during storms when erosion and sediment transport are most acute. The historical development of infragravity wave models and research is discussed as well as infragravity wave dynamics and theoretical generation mechanisms. Field studies identifying infragravity motions are discussed, including the various methods used to measure this complex phenomenon. Considerations for future research including studies to monitor the nearshore morphology, incident wind waves and swell, and infragravity waves are also discussed. These studies would help to understand the link between infragravity energy and nearshore processes (e.g., sediment transport, sandbar generation, beach cusps and other periodic morphologies, rip currents, and runup). An annotated bibliography is included as an appendix. Keywords: Edge waves; Infragravity waves; Nearshore morphology; Runup; Offshore; Sediment transport; Coastal regions. (KT)