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USGS · 70018384

Breakpoint-forced and bound long waves in the nearshore: A model comparison

Jeffrey H. List
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Abstract

A finite-difference model is used to compare long wave amplitudes arising from two-group forced generation mechanisms in the nearshore: long waves generated at a time-varying breakpoint and the shallow-water extension of the bound long wave. Plane beach results demonstrate that the strong frequency selection in the outgoing wave predicted by the breakpoint-forcing mechanism may not be observable in field data due to this wave's relatively small size and its predicted phase relation with the bound wave. Over a bar/trough nearshore, it is shown that a strong frequency selection in shoreline amplitudes is not a unique result of the time-varying breakpoint model, but a general result of the interaction between topography and any broad-banded forcing of nearshore long waves.

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Jeffrey H. List. 1993. Breakpoint-forced and bound long waves in the nearshore: A model comparison. https://pubs.usgs.gov/publication/70018384

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