regards both geometric parameters such as bar volume and depth-to-bar crest, 

 as well as more complex quantities such as the net cross-shore sand transport 

 rate. Any structure or activity extending into the nearshore region is 

 influenced by and exerts influence on the evolution of the beach profile, thus 

 requiring quantitative estimates of profile change under various environmental 

 and design conditions. A thorough analysis of various geometric character- 

 istics of the profile and their dependence on the wave and sand properties is 

 in this respect valuable. Through this analysis the important processes 

 shaping the beach and generating various topographic features may be clari- 

 fied, forming the conceptual framework for a numerical model. 



10. A fundamental assumption of this study is that beach profile change 

 is mainly governed by breaking of short-period waves (periods in the approx- 

 imate range of 3-20 sec). No attempt has been made to include the effect of 

 long-period waves, such as partially standing waves or infragravity waves, in 

 the driving force of profile evolution, because no adequate data on profile 

 change are available that permit firm conclusions to be made. Recent field 

 investigations have indicated that, in some cases, infragravity or long-period 

 wave energy can be more energetic near the shoreline than that of the existing 

 short-period waves. This dominance of the wave energy spectrum in very 

 shallow water by long-period waves is expected to play an important role in 

 beach profile processes on the beach face and, possibly, the inner surf zone. 

 However, no relationship between beach profile change and infragravity waves 

 exists at present due to lack of data. When such data become available, 

 superposition should allow calculation of profile change under both short- and 

 long-period waves. 



11. The main purpose of the data analysis is not to derive widely 

 applicable relationships for geometric properties of the profile, but to 

 identify the important factors governing profile change. These factors will 

 be integral parts in the conceptual foundation underlying the numerical model 

 development. In some cases, however, empirical relationships derived from the 

 data are used directly in the model if general conclusions about the behavior 

 of the quantity can be made. 



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