SAND BYPASSING. See BYPASSING, SAND. 



SAND REEF. BAR. 



SAND WAVE. A large wavelike sediment feature composed of sand in very shallow 

 water. Wavelength may reach 100 meters; amplitude is about 0.5 meter. 

 Also MEGARIPPLE. 



SCARP. See ESCARPMENT. 



SCARP, BEACH. An almost vertical slope along the beach caused by erosion by 



wave action. It may vary in height from a few centimeters to a meter or 



so, depending on wave action and the nature and composition of the 

 beach. (See Figure A-1.) 



SCOUR. Removal of underwater material by waves and currents, especially at 

 the base or toe of a shore structure. 



SEA BREEZE. A light wind blowing from the sea toward the land caused by 

 unequal heating of land and water masses. 



SEA CHANGE. (1) A change wrought by the sea. (2) A marked transformation. 



SEA CLIFF. A cliff situated at the seaward edge of the coast. 



SEA LEVEL. See MEAN SEA LEVEL. 



SEAMOUNT. An elevation rising more than 1000 meters above the ocean floor, 

 and of limited extent across the summit. Compare KNOLL. 



SEA PUSS. A dangerous longshore current; a rip current caused by return flow; 

 loosely, the submerged channel or inlet through a bar caused by those 

 currents. 



SEAS. Waves caused by wind at the place and time of observation. 



SEASHORE. The SHORE of a sea or ocean. 



SEA STATE. Description of the sea surface with regard to wave action. Also 

 called state of sea. 



SEAWALL. A structure separating land and water areas, primarily designed to 

 prevent erosion and other damage due to wave action. See also BULKHEAD. 



SEICHE. (1) A standing wave oscillation of an enclosed waterbody that 

 continues, pendulum fashion, after the cessation of the originating force, 

 which may have been either seismic or atmospheric. (2) An oscillation of 

 a fluid body in response to a disturbing force having the same frequency 

 as the natural frequency of the fluid system. Tides are now considered to 

 be seiches induced primarily by the periodic forces caused by the Sun and 

 Moon. (3) In the Great Lakes area, any sudden rise in the water of a 

 harbor or a lake whether or not it is oscillatory (although inaccurate in 

 a strict sense, this usage is well established in the Great Lakes area). 



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