BREAKER - A wave breaking on a shore, over a reef, etc. Breakers may be 

 classified into four types: 



Spilling - bubbles and turbulent water spill down front face of 

 wave. The upper 25 percent of the front face may become 

 vertical before breaking. Breaking generally across over 

 quite a distance. 



Plunging - crest curls over air pocket; breaking is usually with 

 a crash. Smooth splash-up usually follows. 



Collapsing - breaking occurs over lower half of wave. Minimal 

 air pocket and usually no splash-up. Bubbles and foam 

 present. 



Surging - wave peaks up, but bottom rushes forward from under wave, 

 and wave slides up beach face with little or no bubble produc- 

 tion. Water surface remains almost plane except where ripples 

 may be produced on the beachface during runback. 



BREAKWATER - A structure protecting a shore area, harbor, anchorage, 

 or basin from waves. 



BULKHEAD - A structure or partition to retain or prevent sliding of the 

 land. A secondary purpose is to protect the upland against damage 

 from wave action. 



CLIFF - A high, steep face of rock; a precipice. 



COAST - A strip of land of indefinite width (may be several miles) that 

 extends from the shoreline inland to the first major change in 

 terrain features. 



COASTLINE - (1) Technically, the line that forms the boundary between 

 the COAST and the SHORE. .(2) Commonly, the line that forms the 

 boundary between the land and the water. 



CONTOUR - A line on a map or chart representing points of equal eleva- 

 tion with relation to a DATUM. It is called an Isobath when 

 connecting points of equal depth below a datum. 



COVE - A small, sheltered recess in a coast, often inside a larger 

 embayment . 



CURRENT, LITTORAL - Any current in the littoral zone caused primarily by 

 wave action, e.g., longshore current, rip current. 



CURRENT, LONGSHORE - The littoral current in the breaker zone moving 

 essentially parallel to the shore, usually generated by waves 

 breaking at an angle to the shoreline. 



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