comparison among various cases and to more clearly identify relationships 

 between wave parameters and beach profile evolution. Definition of morpho- 

 logic features with respect to the initial profile involves no limitations in 

 characterizing the behavior of the features or understanding the fundamentals 

 of profile response to wave action. Rather, a clear definition allows strict 

 interpretation of where a bar, berm, or trough is located. Definition of a 

 morphologic feature related to a specific profile has no meaning if a single 

 profile is studied. The objective here is not to advocate a general defini- 

 tion of a bar or other feature applicable to an arbitrary beach profile but to 

 employ a useful definition as a means for understanding the process of beach 

 profile change and facilitating a quantitative description of the dynamic 

 response of morphologic features. 



193. An extensive correlation and regression analysis was carried out 

 to investigate relations between geometric properties of the various morpho- 

 logic features of the profile and the wave and sand characteristics. An 

 overview of the statistical procedures used is given in Appendix A. The 

 primary parameters used were: wave period T or deepwater wavelength L^ , 

 deepwater wave height H^ , breaking wave height Hj, , water depth h , median 

 grain size D , sand fall speed w , and beach slope tan^. Also, various 

 nondimensional quantities were formed, both for deepwater and breaking wave 

 conditions, such as H/L , H/wT , tan/3/(H/L)^'^ , D/H , and D/L , in which H 

 and L are the local wave height and wavelength, respectively. 



Concept of Equilibrium Beach Profile 



194. A fundamental assumption in the study of beach profile change is 

 the existence of an equilibrium profile which a beach will attain if exposed 

 to constant wave conditions for a sufficiently long time. The idea is that 

 the beach profile in its equilibrium state dissipates incident wave energy 

 without significant net change in shape. If an equilibrium profile did not 

 exist, the beach would continue to erode (or accrete) indefinitely if exposed 

 to the same wave conditions and with no restrictions in the sand supply. 



195. The concept of an equilibrium profile is an idealization that 

 cannot be fully achieved in practice, since waves, water level, water tempera- 



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