Chapter 10 — WATCH ROUTINES 



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Figure 10-7.— Sea wave records. 



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Figure 10-8.— Swell wave records. 



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Surf Observations (SUROBS) 



The breaking of waves, in either single or 

 multiple lines, on sloping beaches or on rocky 

 coastlines, is the phenomenon generally known 

 as surf. The surf zone is the areal extent of 

 the breaking waves, from the water up- rush 

 on shore to the most seaward breaker. This 



zone will vary with the slope of the beach 

 and the characteristics of the deep water waves. 

 The safety and success of amphibious land- 

 ings is largely dependent upon known surf con- 

 ditions. It is therefore essential that SUROBS 

 be accurate and timely. The number of ob- 

 servations required will vary with the scope 

 of the exercise. 



187 



