trough to crest. However, often no such point exists on the seaward side of a 

 bar since an immediate trough may not be present. 



189. In the present study, it was found most natural and productive to 

 define morphologic features with respect to the initial profile, since a time 

 sequence of profiles was available. This procedure is, of course, not 

 directly applicable to the field. Areas where sand accretes with respect to 

 the initial profile constitute bar- or berm-like features, whereas areas where 

 material erodes are trough-like in appearance. Figure 4a shows a definition 

 sketch for a beach profile with representative bar and trough features, and 

 Figure 4b illustrates the corresponding berm case. Nomenclature describing 

 the geometric properties is given in the figures, and a typical wave height 

 envelope is outlined in Figure 4a. 



190. As a result of relating bar properties to the initial profile, 

 some properties, such as bar volume, will depend on the initial profile slope. 

 For example, two erosional profiles formed of sand of the same grain size and 

 exposed to the same wave climate will show different equilibrium bar proper- 

 ties if the initial slopes differ. However, the inshore slopes of the 

 equilibrium profile will still be similar (Kamphuis and Bridgeman 1975), but 

 different amounts of material will be redistributed within the profile. In 

 this respect, bar volume is a function of initial profile slope, which makes 

 such a definition less useful in field data analysis for some bar properties. 



191. Definition of morphologic features with respect to the initial 

 profile does not affect net sand transport rate distributions, which only 

 depend upon two consecutively surveyed profiles in time, as will be shown. 

 Furthermore, the main objective of the data analysis is to identify the 

 dominant factors of beach profile change, supporting development of the 

 numerical model. These factors can be distinguished with any reasonable if 

 arbitrary definition of the profile features if it is consistently applied 

 through time. For example, the aforementioned bar definition of Keulegan 

 (1945) would give different values of bar volume with time, but the trend of 

 bar development toward equilibrium and the factors controlling its growth 

 would be similar to those determined by the definition employed here. 



192. Only those cases in the data base with an initially plane profile 

 slope were used in calculation of morphologic features to more easily allow 



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