No. 620) is moored 3 km from shore where the water depth is 18 m; the annual 

 mean significant wave height was 1.06 m, with a 0.64-m standard deviation. 

 The nearshore Baylor gage (gage No. 615), located approximately 100 m from 

 shore in 1.5 m of water, had an annual average significant wave height of 

 0.66 m, with a 0.32-m standard deviation. 



105. Individual data observations show a similar correlation between 

 wave heights and depth; this correlation agrees with the trends of Vincent 

 (1981) whose method for obtaining the maximum energy one could expect in a wind 

 wave sea as a function of the water depth predicts the variation with depth. 



106. Figure 15 presents the annual cumulative distribution of signifi- 

 cant wave heights for the FRF gages for 1980. In general, the probability of 

 high waves increases with water depth at the gage installation. The nearshore 

 Baylor was in very shallow water inside the breaker zone, even during moderate 

 to low wave conditions; consequently, these statistics represent a lower 

 energy wave climate frequently due to waves breaking seaward of the gage. 



107. Figure 16 is a histogram of the peak period distributions. Pe- 

 riods during highest wave conditions varied from 5 to 12 seconds depending on 

 the distance the wave-generating area was from the pier; i.e., storms far off- 

 shore, say 500 km or more, would tend to produce near 12-second wave periods, 

 while more local storms would produce lower periods. Based on the occurrence 

 of periods greater than 10 seconds, swell from very distant generating areas 

 may have accounted for approximately 20 percent of the conditions at the 

 coast. Seasonal, annual, and historic-height-versus-period distributions are 

 presented in Appendix B. 



108. Tables 6 and 7 present seasonal average significant height and 

 peak period values, respectively. The highest waves occurred during January 

 through March, while the lowest occurred during the summer (July-September). 

 From October through December and from January through March, the greatest 

 variety of wave conditions occurred, as reflected in the high standard devia- 

 tions. During January through March, longer average peak periods occurred as 

 compared to April through June when short-period waves dominated. 



109. Wave roses generated for 1980 (see Figure 17) were based on visual 

 measurements of the direction at which the primary wave train (i.e., the wave 

 train having the largest heights) approached; these measurements were made 

 daily (near 0700) at the seaward end of the FRF pier. Wave height was 

 determined from the pier end Baylor staff gage at a corresponding time. The 



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