STANDING WAVE. A type of wave in which the surface of the water oscillates 

 vertically between fixed points, called nodes, without progression. The 

 points of maximum vertical rise and fall are called antinodes or loops. 

 At the nodes, the underlying water particles exhibit no vertical motion, 

 but maximum horizontal motion. At the antinodes, the underlying water 

 particles have no horizontal motion, but maximum vertical motion. They 

 may be the result of two equal progressive wave trains traveling through 

 each other in opposite directions. Sometimes called CLAPOTIS or 

 STATIONARY WAVE. 



STATIONARY WAVE. A wave of essentially stable form which does not move with 

 respect to a selected reference point; a fixed swelling. Sometimes called 

 STANDING WAVE. 



STILL-WATER LEVEL. The elevation that the surface of the water would assume 

 if all wave action were absent. 



STOCKPILE. Sand piled on a beach foreshore to nourish downdrift beaches by 

 natural littoral currents or forces. See FEEDER BEACH. 



STONE, DERRICK. Stone heavy enough to require handling individual pieces by 

 mechanical means, generally weighing 900 kilograms (1 ton) and up. 



STORM SURGE. A rise above normal water level on the open coast due to the 



action of wind stress on the water surface. Storm surge resulting from a 



hurricane also includes that rise in level due to atmospheric pressure 



reduction as well as that due to wind stress. See WIND SETUP. 



STORM TIDE. See STORM SURGE. 



STRAIT. A relatively narrow waterway between two larger bodies of water. See 

 also SOUND. 



STREAM. (1) A course of water flowing along a bed in the Earth. (2) A 

 current in the sea formed by wind action, water density differences, etc.; 

 e.g. the Gulf Stream. See also CURRENT, STREAM. 



SURF. The wave activity in the area between the shoreline and the outermost 

 limit of breakers. 



SURF BEAT. Irregular oscillations of the nearshore water level with periods 

 on the order of several minutes. 



SURF ZONE. The area between the outermost breaker and the limit of wave 

 uprush. (See Figures A-2 and A-5.) 



SURGE. (1) The name applied to wave motion with a period intermediate between 

 that of the ordinary wind wave and that of the tide, say from 1/2 to 60 

 minutes. It is low height; usually less than 0.9 meter (0.3 foot). See 

 also SEICHE. (2) In fluid flow, long interval variations in velocity and 

 pressure, not necessarily periodic, perhaps even transient in nature. (3) 

 see STORM SURGE. 



SURGING BREAKER. See BREAKER. 



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