Sample correlation coefficients computed for the open circle data on 

 Figure 18 gave 0.45 between Atlantic City and Ludlam Island and -0.60 

 between Atlantic City and Long Beach Island. There is a general decrease 

 in sample mean between the samples collected in March 1968 and those col- 

 lected in October 1968, but there is no obvious annual cycle. 



Monthly changes seem greater at Ludlam Island. The maximum variation 

 in sample mean during 1 year for any one beach was 0.52 phi [0.083 milli- 

 meter) (October 1968 to March 1969 for Ludlam Island) and the maximum 

 variation over 1 month for any one beach was 0.29 phi (0.065 millimeter) 

 (February to March 1969 for Long Beach Island). This 1-month variation 

 also happens to be the maximum variation for 1 year on Long Beach Island. 



Data collected between 1954 and 1965 (Galvin, et al., 1969) show 

 that the surf on the north Atlantic coast is least active during the months 

 of June and July and most active from August to March. Unfortunately, no 

 sand samples were collected for sample set A from April through September. 

 Also, insufficient 1968-69 wave data from the sample area were available 

 to make any correlation between sample mean and wave activity at the time 

 of sample collection. 



5. Comparison with McMaster's Data . 



McMaster (1954) collected samples only along the latest high tide line 

 on the beach and, consequently, most of his samples probably come from the 

 berm to MHW segment of the profile, using the definitions which appear in 

 Figure 9. Therefore, to make CERC's data comparable to his, only those 

 samples taken from this berm to MHW segment were used to compute CERC's 

 RSA and sample means in Table 4. 



Table 4 shows that CERC's sample means are only slightly coarser than 

 McMaster's for Long Beach Island, but for the other two localities CERC's 

 data show a considerably coarser mean. It should be noted that McMaster 

 collected his samples during late June and early August when there is 

 usually less surf activity and, perhaps, finer particles on the beach. 

 Since sample set A lacks samples collected during the summer months, such 

 a seasonal effect may be the reason for CERC's data showing a coarser 

 mean. Figure 18 shows month-to-month variations, even without summer sam- 

 ples, as great as 0.065 millimeter in CERC data, which is on the same order 

 as the maximum difference (0.079 millimeter) between CERC and McMaster's 

 data. 



6. Sample Mean versus Slope . 



Many investigators have found that slope of the beach face is related 

 to sand size (Bascom, 1951; U.S. Army, Corps of Engineers, Coastal Engi- 

 neering Research Center, 1975, p. 4-86). For New Jersey beaches, McMaster 

 (1954) found that "coarse and medium sands are restricted to gentle and 

 moderately inclined foreshores and fine sands occur on nearly flat shores;" 

 Urban and Galvin (1969) noted that slope of the beach face and general 



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