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It is widely assumed that incident bound long waves are released during short wave breaking, subsequently propagating to the shore as a free wave. Statements asserting this release are either unattributed, or loosely attributed to Longuet-Higgins and Stewart (1962). However, the author is unaware of convincing evidence of such release of bound long waves as a result of short wave breaking, while there appears to be strong evidence to the contrary. The author's interpretation is that Longuet-Higgins and Stewart (1962) suggest that the bound wave will decay in amplitude following short wave breaking. This is in agreement with a number of the author's data sets and some data from other recent data sets, including field observations of strong nearshore dissipation of long waves. A surf beat similarity parameter is also suggested, which distinguishes different regimes of surf beat generation.

This paper investigates the spectral characteristics of low frequency fluctuations of natural wind velocity and atmospheric pressure, and the resonant evolution of long period waves by low frequency fluctuations of winds in a laboratory experiment. Laboratory experiments on the responses of wind waves under periodically fluctuating winds have been conducted to find an alternative generation mechanism for long period waves. The experiments show that the long period waves developed at the peak frequency of the low frequency fluctuations of wind speed and air pressure. Through the spectral analysis of fluctuating components of wind speed, air pressure and water surface elevation, the long period waves are found to be generated and resonantly developed by the fluctuating components of surface shear stress due to periodically fluctuating wind speed.

The highly transient initial shapes of 1D forced long waves are described in analogy with the swinging up of a mass on a spring forced by a simple harmonic force. That is, the complete solution is seen as the asymptotic, steady forced wave plus free waves which cancel it in the initial state of rest. The highly transient, complete wave form subsequently grows as the free waves separate from the forced wave. This approach gives a clear understanding of many of the characteristics of storm surge, tsunami and surfbeat.

The shore behind the offshore fishing port has never been attached to the facility for 15 years after the construction. The main object is to investigate the littoral drift behavior around the port. As the result of wave and current observation, the differences in the time-averaged surface elevation were found at the right and left sides during typical storm. By using a volumetric analysis and a simple method to estimate the longshore sediment transport rate, 55 percents of the net longshore sediment transport is estimated to go through behind the port. In this study, a numerical simulation is applied and gives a good validation against the observed data and estimates the current field and suspended sediment transport during typical storm to understand the littoral drift behavior.