Figure 11. Annual wind distribution by percent frequency and mean speed for 

 Atlantic City. Data obtained from SSMO (U.S. Naval Weather Serv- 

 ice Command, 1970) collected during 1949-68 and covering the area 

 from 38° to 40° N. latitude and 72° W. longitude to the coast. 



result in a southwest, or "down-beach drift"; waves from west of the normal 

 produce a northeast, or "up-beach drift." Results from visual wave observa- 

 tions obtained at different times at Atlantic City indicate that waves east of 

 the normal occur greater than 50 percent of the time (Figs. 12 and 13). An 

 earlier report by the U.S. Army Engineer District, Philadelphia (1938), also 

 indicated a predominant down-beach drift occurring about 48 percent of the 

 time compared to about 24 percent up-beach drift and 28 percent onshore- 

 offshore drift. 



CERC maintained a relay-type wave gage on the end of Steel Pier (5.2 

 meters mean water depth) from 1962 to 1969, which measured water surface ele- 

 vations in 6-centimeter increments. These data, analyzed by Thompson (1977), 

 indicate that during 1964 to 1967 the average significant wave height and 

 average wave period increased substantially in September (Fig. 14). This is 

 also in general agreement with Figure 4-10 in the Shore Protection Manual 

 (SPM) (U.S. Army, Corps of Engineers, Coastal Engineering Research Center, 

 1977). The explanation for this behavior during this particular period is 

 shown in Figures 15 and 16 which give the values by month for each of the 

 years considered. The peak in values of period and height during September 

 1964 can be attributed to Hurricanes Dora, Ethel, and Gladys offshore along 

 the Atlantic coast. Although none of these hurricanes directly hit New 

 Jersey, they generated large waves which reached the shore. Historically, 

 there is a substantial increase in tropical cyclones and hurricanes in 

 the North Atlantic Ocean during September (Fig. 17); however, only a few 



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