96. Figures 13, 15, and 17 display the results of the wave model, at 

 cell centers, corresponding to waves coming from three different directions. 

 These are waves 22, 45, and 59 from Table 3. These three conditions will be 

 referred to as cases A, B, and C, respectively. For all three cases, the 

 significant wave height in 63-ft depth of water msl is identical and equal to 

 7.4 ft. The period is roughly the same. The wave directions are quite 

 different. In each of the figures, the length of an arrow (vector) is 

 proportional to the wave height (a scale is shown), and the direction of the 

 arrow indicates the direction in which the waves are progressing. For 

 clarity, only vectors for alternate cells in each coordinate direction are 

 plotted. 



97. Figures 14, 16, and 18 present the wave-induced currents at grid 

 cell centers corresponding to cases A, B, and C. In these figures, the length 

 of an arrow is proportional to the magnitude of the current (a scale is shown) , 

 and the direction of the arrow Indicates the direction of the current. The 

 currents are depth-averaged. For convenience and clarity, only vectors in 

 alternate cells in each coordinate direction are plotted. 



98. Figure 13 corresponds to a wave of period 7.2 sec coming from 

 azimuth 120 deg in 63-ft depth msl (Case A) . The waves respond to the off- 

 shore shoal. The wave height increases, and the wave direction changes as the 

 waves go over the shoal. The wave height decreases, and the waves resume 

 their original direction once the waves pass the shoal. The waves converge on 

 the south shoal due to refraction, move parallel to the jetty, and break on 

 the shoal. Because of the sheltering effect of the south jetty, very little 

 of the Incident wave energy goes past the jetty tips into the Inlet. Note 

 also the sheltering effect behind the north jetty resulting in very little 

 wave action there. The waves converge on the north shoal, and the wave energy 

 spreads out (diverges) due to a "bay" effect as the waves reach the shoreline 

 of Cumberland Island. Near the approximately straight shorelines of both bar- 

 rier islands, the wave height decreases because of wave breaking and decay. 



99. Figure 14 shows the wave-induced currents corresponding to Case A. 

 Near the straight part of the shorelines of Amelia and Cumberland Islands, the 

 currents are mainly parallel to the shore and move to the north. However, 

 near the south shoal, because of wave refraction and breaking, the currents 

 tend to move in a westerly direction. The net result is the counterclockwise 

 circulation we see over the shoal. The currents are the largest in this 



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