frequency band width of 0.0117 Hz). 



37. Wave period T is defined as the period associated with the 

 maximum energy band in the spectrum which is computed using a 3 -point running 

 average band on the spectrum. The peak period is reported as the reciprocal 

 of the center frequency (i.e., T = 1/frequency) of the spectral band with 

 the highest energy. A detailed description of the analysis techniques is 

 presented in a report by Andrews (1987).* 



Results 



38. The wave conditions for the year are shown in Figure 9. For all 

 four gages, the distributions of wave height for the current year and all 

 years combined are presented in Figures 10 and 11, respectively. Distribu- 

 tions of wave period are presented in Figure 12. 



39. Multiple year comparisons of data for Gage 111 actually incorporate 

 data for 1985 and 1986 from Gage 640, a discontinued Waverider buoy previously 

 located at the approximate depth and distance offshore as Gage 111 and data 

 for 1987 from Gage 141, located 30 m south of Gage 111. 



40. Refraction, bottom friction, and wave breaking contribute to the 

 observed differences in height and period. During the most severe storms when 

 the wave heights exceed 3 m at the seaward end of the pier, the surf zone 

 (wave breaking) has been observed to extend past the end of the pier and 

 occasionally 1 km offshore. This occurrence is a major reason for the dif- 

 ferences in the distributions between Gage 630 and the inshore gages. The 

 wave height statistics for the staff gage (Gage 645) , located at the landward 

 end of the pier, were considerably lower than those for the other gages. In 

 all but the calmest conditions, this gage is within the breaker zone. 

 Consequently, these statistics represent a lower energy wave climate. 



* M. E. Andrews. 1987. "Standard Wave Data Analysis Procedures for Coastal 

 Engineering Applications," unpublished report prepared for the US Army 

 Engineer Waterways Experiment Station, Vicksburg, MS. 



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