erosion or accretion trends at a profile line. Also, even when trends 

 are apparent, some appear to be "stronger" at some locations than at 

 others. In order to quantify this, heretofore, subjective evaluation 

 of the main factor describing the beach activity, erosion versus accretion, 

 a statistical scheme was developed and first used in Goldsmith, Farrell, 

 and Goldsmith (1974a). This scheme was adopted in this study, and is 

 described below. 



To test for statistically significant erosion or accretion trends 

 at each beach profile line, a linear regression line was calculated for 

 cumulative beach volume change against time (in weeks) using a stand- 

 ard canned program on the VIMS IBM 370 computer. The null hypothesis 

 assumed that the calculated regression line represented the distribu- 

 tion of beach volume change with time (i.e., significantly different 

 from chance within the 27 months of survey measurements) . This was 

 tested at various levels of statistical significance (e.g., 1, 5, 10, 

 and 50 percent) and the null hypothesis was accordingly rejected at 

 the appropriate significant level, and the erosion-accretion trend 

 was considered to be statistically significant at that level. It is 

 interesting to note that all eight profile lines exhibiting trends 

 considered statistically significant (at 1 percent level) showed a 

 large statistical difference from the other profile lines (i.e., 

 there was a major break in the groupings of the significance levels) . 



7. Ground Photography. 



Numerous 35-millimeter color slides were taken on each of the sur- 

 veying trips. Views up and down the beach, as well as along the 

 profile line, were included along with other interesting features such 

 as scarps, vegetation, surf conditions, and usage. These slides are 

 stored in the Coastal Engineering Information Analysis Center at 

 CERC. 



Photographs of various beach conditions at each of the 18 profile 

 lines are in Appendix A. 



8. Aerial Inspection . 



Aerial flights were made over the study area at altitudes between 

 130 and 300 meters, as close to the time of surveying as weather 

 permitted. Oblique 35-millimeter color slides generally overlap, 

 showing the beach area between the profile lines, as well as the 

 profile sites. Beach features such as scarps, overwash areas, dune 

 orientation, suspended sediment plumes in the surf zone, and near- 

 shore bars can be readily seen in slides taken from low-altitude 

 aircraft . 



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