^. Persistence of wave heights. Tables B6, B16, and B26 show the 



number of times throughout 1984 when the specified wave height was 

 equaled or exceeded at least once during each day for the duration 

 (consecutive days) indicated; data for 1980 through 1984 are in 

 Tables Bll, B21, and B31. For example, Table B6 for gage 625 

 (pier-end Baylor) indicates wave heights equaled or exceeded 1.0 m 

 49 times for at least 1 day; 34 times for at least 2 days; 23 times 

 for at least 3 days; 15 times for at least 4 days, etc. Therefore, 

 on 15 occasions, the height equaled or exceeded 1.0m for 1 day 

 exactly; on 11 occasions for 2 days; on 8 occasions for 3 days, etc. 

 Note that the height exceeded 1 m 49 times for 1 day or longer, 

 while heights exceeded 0.5 m only 22 times for this same duration. 

 This occurred because the longer durations of lower waves may be 

 interspersed with shorter, but more frequent, intervals of higher 

 waves. For example, the one time that wave heights exceeded 0.5 m 

 for 62 days may represent 5 or 10 times the height exceeded 1 m for 

 shorter durations. 



h. Visual wave observation roses. Wave heights from the pier-end 



Baylor gage (625) , and visually observed wave approach angles are 

 combined to produce wave direction versus height distributions. 

 Data for 1984 are in Figures B9 and BIO, while 1980 through 1984 

 data are in Figures B18 and B19. The angles are referenced to true 

 north. Northerly wave angles (e.g. less than 70 deg) generally 

 produce southward currents while southerly wave angles greater than 

 70 deg produce northward currents. 



i. Spectra. Spectra for the pier-end Baylor gage (625) for days when 

 wave heights exceeded 2 m are presented in Figure B46. The plots 

 show energy density as a function of wave frequency. 



B2 



