NEARSHORE CURRENT SYSTEM. The current system caused primarily by wave action 

 in and near the breaker zone, and which consists of four parts: the 

 shoreward mass transport of water; longshore currents; seaward return 

 flow, including rip currents; and the longshore movement of the expanding 

 heads of rip currents. (See Figure A-7.) See also NEARSHORE CIRCULATION. 



NECK. (1) The narrow band of water flowing seaward through the surf. Also 

 RIP. (2) The narrow strip of land connecting a peninsula with the 

 mainland. 



NIP. The cut made by waves in a shoreline of emergence. 



NODAL ZONE. An area in which the predominant direction of the LONGSHORE 

 TRANSPORT changes. 



NODE. That part of a STANDING WAVE where the vertical motion is least and the 

 horizontal velocities are greatest. Nodes are associated with CLAPOTIS 

 and with SEICHE action resulting from wave reflections. Compare LOOP. 



NOURISHMENT. The process of replenishing a beach. It may be brought about 

 naturally by longshore transport, or artificially by the deposition of 

 dredged materials. 



OCEANOGRAPHY. The study of the sea, embracing and indicating all knowledge 

 pertaining to the sea's physical boundaries, the chemistry and physics of 

 seawater, and marine biology. 



OFFSHORE. (1) In beach terminology, the comparatively flat zone of variable 

 width, extending from the breaker zone to the seaward edge of the 

 Continental Shelf. (2) A direction seaward from the shore. (See Figure 

 A-1.) 



OFFSHORE BARRIER. See BARRIER BEACH. 



OFFSHORE CURRENT. (1) Any current in the offshore zone. (2) Any current 

 flowing away from shore. 



OFFSHORE WIND. A wind blowing seaward from the land in the coastal area. 



ONSHORE. A direction landward from the sea. 



ONSHORE WIND. A wind blowing landward from the sea in the coastal area. 



OPPOSING WIND. In wave forecasting, a wind blowing in a direction opposite 

 to the ocean-wave advance; generally, a headwind. 



ORBIT. In water waves, the path of a water particle affected by the wave 

 motion. In deepwater waves the orbit is nearly circular, and in shallow- 

 water waves the orbit is nearly elliptical. In general, the orbits are 

 slightly open in the direction of wave motion, giving rise to MASS 

 TRANSPORT. (See Figure A-3.) 



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