WAVE HINDGASTING - The calculation from historic synoptic wind charts of 

 the wave characteristics that probably occurred at some past time. 



WAVE LENGTH - The horizontal distance between similar points on two 

 successive waves measured perpendicularly to the crest, 



WAVE, OSCILLATORY - A wave in which each individual particle oscillates 

 about a point with little or no permanent change in position. The 

 term is commonly applied to progressive oscillatory waves in which 

 only the form advances, the individual particles moving in closed or 

 nearly closed orbits. Distinguished from a WAVE of TRANSLATION. See 

 also ORBIT o 



WAVE PERIOD - The time for a wave crest to traverse a distance equal to 

 one wave length. The time for two successive wave crests to pass a 

 fixed point. See also SIGNIFICANT WAVE PERIOD, 



WAVE, PROGRESSIVE - A wave which is manifested by the progressive move- 

 ment of the wave form, 



WAVE PROPAGATION - The transmission of waves through water. 



WAVE RAY - See ORTHOGONAL. 



WAVE, REFLKITED - The wave that is returned seaward when a wave impinges 

 upon a very steep beach or barrier, 



WAVE REFRACTION - (l) The process by which the direction of a train of waves 

 moving in shallow water at an angle to the contours is changed. The 

 part of the wave train advancing in shallower water moves more slowly 

 than that part still advancing in deeper water, causing the wave 

 crests to bend toward alinement with the underwater contours. (See 

 Figures A-5 and A-6), (2) The bending of wave crests by currents. 



VJAVE, SEISMIC - A TSUNAi'4I„ A generally long period wave caused by an 



underwater seismic disturbance or volcanic eruption. Commonly mis- 

 named "tidal wave", 



WAVE, SOLITARY - A wave consisting of a single elevation (above the 



water surface) of height not necessarily small compared to the depth 

 and neither followed nor preceded by another elevation or depression 

 of the water surfaces. 



WAVE, STANDING - A type of wave in which there are nodes, or points of no 

 vertical motion and maximum horizontal motion, between which the 

 water oscillates vertically. The points of maximum vertical motion 

 and least horizontal motion are called antinodes or loops. It is 

 caused by the meeting of two similar wave groups travelling in opposing 

 directions. 



A-39 



