rate of transfer of energy from the wind to the waves, the maximum 

 height allowed, and the distribution of wave energy among the various 

 frequencies. (author's abstract) 



Coastal Engineering Significance . The interaction between turbulence 

 and waves has been reported anecdotally by several observers and can 

 easily be appreciated by observing the wake of a powerboat moving 

 perpendicular to the wind in a light chop. However, there have been few 

 reports on the subject other than the one referenced here. 



52. SKOVGAARD, 0., JONSSON, I.G., and BERTELSEN, J.A., "Computation of 

 Wave Heights Due to Refraction and Friction," Journal of the 

 Waterways, Harbors, and Coastal Engineering Division, Vol. 101, No. 

 WWl, Feb. 1975, pp. 15-32. 



Keywords. Depth Refraction; Wave Energy; Wave Height; Waves; Waves, 

 Ocean; Waves, Surface. 



Discussion. The equations for the wave orthogonals and the wave heights 

 are presented for depth refraction of regular, long-crested, small- 

 amplitude surface gravity waves over an arbitrary bottom, using time as 

 the independent variable. The effect of turbulent bottom friction on 

 the wave height is included. The computer outputs are in the form of 

 automatically plotted wave orthogonals with the wave heights written at 

 discrete points along these paths. Systematic tests are presented for 

 water areas with straight and parallel bottom contours. The errors 

 inherently connected with the introduction of a grid plus a set of 

 formulas for the differentiation and interpolation are examined for a 

 horizontal bottom with an infinitely long sinusoidal threshold. For one 

 plane sloping bottom, information is given for the influence of the 

 initial curvature of the wave front, bottom roughness, and initial wave 

 height, (authors' abstract) 



Coastal Engineering Significance. This is one of the relatively few 

 engineering papers in the United States directly tied to the European 

 tradition of wave-current interaction. The paper is an attempt at a 

 numerical approach to the subject, which is the important long-term 

 objective according to the several investigators. 



53. SMITH, R., "Giant Waves," Journal of Fluid Mechanics, Cambridge, 

 England, Vol. 77, No. 3, Oct. 1976, pp. 417-431. 



Keywords . Caustics; Current Refraction; Currents, Large-Scale; Cur- 

 rents, Opposing; Flow, Irrotational; Stability; Theory; Wave Profiles; 

 Waves, Nonlinear. 



Discussion. Waves propagating against adverse currents, particularly 

 near the boundaries of such currents, have given cause for concern. In 

 this paper a perturbation analysis is carried out to find an equation 



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