hurricanes directly impact on Atlantic City (two "direct hits" from 1899-1977 

 were recorded by the National Weather Service, 1978). Most hurricanes remain 

 offshore in this area, producing indirect effects such as increased wave 

 heights. Extratropical storms, particularly northeasters, are second only to 

 hurricanes in their destructive intensity causing considerable damage to the 

 beaches and structures along the New Jersey coast. The resultant damage from 

 these storms is largely due to the high winds, waves, and increased water 

 levels they generate. 



The astronomical tides at Atlantic City are semidiurnal and have been mon- 

 itored almost continuously since 1912 from a primary tide station located on 

 Steel Pier. The mean tidal range is 1.25 meters, with the normal tidal range 

 varying from 0.98 meter for neap tides to 1.52 meters for spring tides. The 

 highest recorded storm tide at Atlantic City, 2.32 meters above MSL (Table 2), 

 occurred during a hurricane in September 1944. The March 1962 storm caused 

 the second highest storm tide, 2.19 meters above MSL (Table 2). Additional 

 information on extreme high tides and frequency of maximum monthly high tides 

 is provided in Table 3 and Figure 18, respectively (U.S. Congress, 1964a). 



The National Ocean Survey's (NOS) accepted mean tidal heights for this 

 location, based on the timespan 1948 to 1966, referenced to the ocean MLW 

 datum, are: mean high water (MHW), 1.25 meters; mean tide level, 0.62 meter; 

 National Geodetic Vertical Datum (NGVD) , 0.50 meter; and MSL, 0.63 meter. 

 During the period 1912 to 1969, the apparent secular trend for the change in 

 sea level at Atlantic City was a rise of 0.283 centimeter per year (Hicks, 

 1972). Approximately 0.1 centimeter per year of this change is due to the 

 glacial-eustatic rise in sea level, with the remainder attributed to 

 subsidence. 



The seemingly minor, but never-ending changes in sea level (Fig. 19), 

 spanning years and decades, are masked by the more dramatic changes due to the 

 meteorological and oceanographic parameters affecting the yearly variability 

 in sea level. These include variations in wind, currents, water temperature, 

 salinity, river discharge, and direct atmospheric pressure (Hicks, 1972). 



Table 4 provides a summary of physical characteristics relating to 

 Atlantic City. 



III. DATA COLLECTION AND ANALYSIS 



1. Establishment of Profile Lines. 



Seven profile lines were established along azimuths normal to the shore- 

 line in 1962 (Fig. 1). The spacing between adjacent profile monuments gener- 

 ally increased from profile lines 1 to 7 with the smallest distance between 

 profile lines 1 and 2 at 426 meters, and the greatest distance between profile 

 lines 6 and 7 at 1.62 kilometers. Some of these monuments were, however, 

 offset from the actual profile lines. Standard bronze Corps of Engineers' 

 disks were placed on or near profile lines 1 to 4, and 6 in 1975, and profile 

 lines 5 and 7 in 1976. Each monument was then referenced horizontally to the 

 New Jersey Transverse Mercator and vertically to NGVD (sea level datum of 



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