from the overall changes that although the median change was for -15.6 m^/m 

 of erosion, one profile showed in excess of 50 m^/m of accretion. From Table 

 3, this was profile line 1, which is located adjacent to the south jetty of 

 Absecon Inlet and tends to experience much greater changes than the other 

 profile lines. The plot also indicates that most of this accretion occurred 

 between the 1- and 1.5-m contours. As expected, the mean overall volume 

 change of -1.21 was greatly affected by profile line 1 while the median was 

 not affected. 



16. Though this report uses the median to typify the storm changes, 

 for planning purposes in estimating erosion it may be better and more 

 conservative to use the low hinge values. 



Wave Data 



17. One major shortcoming of many beach profile studies is the lack of 

 consistent wave information. Though daily visual wave observations and wave 

 gage records at many of the BEP localities are available, they are neither 

 consistent nor frequent enough for intercomparisons between different 

 localities. The Phase III of the WIS for the Atlantic coast (Jensen 1983) 

 provides hindcasts of wave height, period, and direction every 3 hours at 

 stations located every 16 km (10 nautical miles) along the east coast. The 

 data cover the 20-year period from 1956 through 1975, and include the 10 

 years of the BEP surveys. Hindcast data do not exist for the data collected 

 under the Storm Erosion Studies. 



18. The Phase III hindcast is the final of three phases. In Phase I 

 (Corson et al. 1981) deepwater wave data were hindcast from surface air 

 pressure and wind data over the Atlantic Ocean. Phase II (Corson et al. 

 1982) took the Phase I deepwater hindcasts and accounted for the sheltering 

 effects and local wind sea growth of the Continental Shelf. Phase III is a 

 transformation of the Phase II results into shallow water (10 m) . Note that 

 the current formulation of the hindcast data does not include waves generated 

 by hurricanes and tropical cyclones. Figure 4 identifies the Phase III 

 locations used for this study. 



19. Several important assumptions are used during the generation of 

 Phase III data: 



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