67. The use of the entire grain-size distribution gives a detailed 

 picture of the sediment distribution at each sampling location showing bimodal 

 versus unimodal distributions, as well as changes in specific size classes in 

 response to wave action. The use of composite samples reduces the variability 

 and allows large data sets, such as in this study, to be analyzed and trends 

 to be identified. The choice of sediment statistics used to characterize a 

 sediment is important. The most used grain-size descriptor in modeling 

 efforts is the use of the median (Djo) . The mean grain size is probably the 

 most reported statistic. These two values are very similar except in 

 polymodal sediment distributions, such as were found in the beach group. A 

 comparison of the composite means of the beach, entire profile, and nearshore 

 groups gives a better picture of temporal cross -shore change than any one 

 individual sample mean. This study indicated that the most variability was 

 found in the beach group, whereas the nearshore composite means were the least 

 variable and indicated only changes due to high wave events. The use of the 

 profile composite mean fell between them and gave a reasonable picture of 

 grain- size changes. 



68. Any modeling effort that requires grain-size data should evaluate 

 the cross -shore variability of that particular beach and should choose either 

 a composite of the subaerial berm and foreshore portion of the beach or the 

 total profile to characterize the sediment distribution. Since most equations 

 require a single value, the use of a beach or profile composite mean is sug- 

 gested to give the best representation. 



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