PART IV: QUANTIFICATION OF MORPHOLOGIC FEATURES 



183. The literature review presented in Part II revealed the remarkable 

 fact that relatively few studies have been made to quantitatively characterize 

 the shape of the beach profile. Even fewer studies have attempted to deter - 

 ministically describe the response of the profile to the waves incident upon 

 it. Development of a quantitative description of the observed dynamics of the 

 profile in terms of the incident waves, therefore, appeared to be a valuable 

 approach with which to begin this investigation, as well as a logical and 

 necessary one in the path toward development of a predictive model of profile 

 change. Precise knowledge of the morphology and dynamics of the profile is 

 necessary both for understanding of the subject being studied and development 

 of the predictive model . 



184. As discussed in Part I, at this first stage of developing a 

 quantitative deterministic description of the beach profile and its change, 

 use of data obtained in experiments performed with large wave tanks was judged 

 to be the best approach. The experiment condition of regular waves is 

 considered an advantage for isolating the effect of breaking waves on the 

 beach. The authors believe this to be the dominant process producing bar 

 formation and much of the change in the beach profile under most environmental 

 conditions. Solid understanding of profile change produced by breaking waves 

 will further understanding of other possible contributing processes, since in 

 nature all forcing agents act concurrently and their individual contributions 

 are difficult to distinguish. Firm knowledge of one will aid in understanding 

 the others. 



185. The main purpose of the analysis described in this chapter is to 

 establish the most important parameters governing beach profile evolution in 

 terms of the wave and sediment characteristics. This procedure is expected to 

 provide fundamental information on the response of the profiles and facilitate 

 a physically based approach for development of the numerical model. The 

 results are of interest in themselves in understanding beach profile response 

 as well as for computation of cross-shore sand transport rates and profile 

 change. Clear connections between cause (waves) and effect (profile change) 

 as elucidated in the large wave tanks is expected to provide guidance for 



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