OLR (1983) 30 (12) A. Physical Oceanography 909

83:6636 Laing, A.K., 1983. A numerical ocean wave model for

the southwest Pacific. N.Z. Jl mar. Freshwat. Res., 17(1):83-98.

A computer-based model for forecasting ocean waves in the SW Pacific is described. Wave gener- ation and dissipation are calculated using an empir- ically derived exponential formula. Some results are presented and hindcasts for selected weather events are discussed. New Zealand Meteorol. Serv., Min. of Transport, P.O. Box 722, Wellington, New Zealand.

83:6637 Meiron, D.I. and P.G. Saffman, 1983. Overhanging

interfacial gravity waves of large amplitude. J. Fluid Mech., 129:213-218.

Methods to investigate the existence of overhanging gravity waves of permanent form at the interface between 2 uniform fluids of different density are discussed. Numerical results which demonstrate their existence are presented. Appl. Math., Calif. Inst. of Tech., Pasadena, Calif. 91125, USA.

83:6638 Pefia, H.G., 1983. On the stability of the moments of

the maximum entropy wind wave spectrum. Ocean Engng, 10(2):79-96.

A sea surface profile was simulated and its wave energy spectrum estimated by the Maximum Entro- py Method. Under varying degrees of freedom of the MEM spectral estimation, results show a much better stability of wave parameters compared to the classical periodogram and correlogram spectral approaches; stability of wave parameters as a function of high-frequency cut-off is the same as obtained by the classical techniques. Centro de Invest. Cient. y de Educ. Sup. de Ensenada, Baja California, Mexico.

83:6639 Ryrie, S.C., 1983. Longshore motion generated on

beaches by obliquely incident bores. J. Fluid Mech., 129:193-212.

Numerical solutions of the 2-D shallow-water equa- tions are found for motion on a sloping beach generated by a single bore and by a periodic succession of bores, both incident at small angles. For the latter, periodic longshore motion always can be found if bottom friction is included. Timescale of the development of longshore motion is considered. Dept. of Computer Studies and Math., Bristol Polytech., UK.

83:6640 Sprinks, Tudor and Ronald Smith, 1983. Scale

effects in a wave-refractlon experiment. J. Fluid Mech., 129:455-471.

Experimental results of Provis (1975, 1976) for wave amplification at a conical island bear little resem- blance to the theoretical predictions of Smith and Sprinks (1975). Provis's suggestion, that his exper- iments were dominated by viscous damping and by standing waves between the island and the wave- maker, is confirmed. Estimates are given as to how large an experiment needs to be to avoid these scale effects. Dept. of Math., Univ. of Essex, UK.

83:6641 Tayfun, M.A., 1983. Effects of spectrum band width

on the distribution of wave heights and periods. Ocean Engng, 10(2): 107-118.

A theoretical expression for the joint distribution of crest-to-trough wave heights and zero up-crossing periods is developed from a modified extension of data relevant to wave envelopes and periods under narrowband conditions; the probability structure is explored explicitly with respect to effects associated with the spectrum band width. Results show that the Rayleigh distribution, often used in predicting crest-to-trough heights, is not accurate. Analysis is extended to establish the validity of an approximate expression for the distribution of crest-to-trough heights (Tayfun, 1981). Civil Engrg. Dept., Kuwait Univ., P.O. Box 5969, Kuwait.

83:6642 Tayfun, M.A., 1983. Nonlinear effects on the dis-

tribution of crest-to-trough wave heights. Ocean Engng, 10(2):97-106.

The statistical distribution of the crest-to-trough heights of narrowband nonlinear sea waves is derived in a semi-closed form; resulting density and exceedance probability distributions are compared with those of the linear theory. Nonlinearity has an insignificant influence on the distribution of crest- to-trough heights. Civil Engrg. Dept., Kuwait Univ., P.O. Box 5969, Kuwait.

AI70. Wind-wave interactions

83:6643 Anisimova, E.P., V.I. Makova, A.A. Speranskaya

and M.S. Tugeyeva, 1983. Momentum transfer from wind to sea waves. Fiz. A tmosf. Okeana, 19(4):434-438. (In Russian.)