Peak Spectral Wave Period Distributions 



Annual and monthly peak wave period 7^ distribution histograms for 1995 

 are presented in Figures B5 and B6. Data for 1980 through 1995 are presented 

 in Figure B7. 



Persistence of Wave Heights 



Table B5 shows the number of times in 1995 when the specified wave 

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

 (consecutive days). Data for 1980 through 1995 are averaged and given in Ta- 

 ble B6. An example is shown below: 



Height 

 m 













Consecutive Dav(s) or Lonqer 















_1 

 18 



J. 

 15 



JL 



4 

 14 



5 

 13 



6_7_8_9 10111213 

 12 11 10 9 



14 

 8 



15 



16 



7 



12 



18 



19± 



0.5 



1.0 



50 



34 



24 



21 



18 



14 12 8 7 3 2 















1.5 



41 



19 



8 



6 



2 



1 















2.0 



22 



9 



5 



1 



















2.5 



10 



5 



2 





















3.0 



6 



1 























3.5 





1 























4.0 



1 

























This example indicates that wave heights equaled or exceeded 1.0 m 

 50 times for at least 1 day; 34 times for at least 2 days; 24 times for at least 

 3 days, etc. Therefore, on 16 occasions the height equaled or exceeded 1.0 m 

 for 1 day exacdy (50 - 34 = 16); on 10 occasions for 2 days; on 3 occasions 

 for 3 days, etc. Note that the height exceeded 1 m 50 times for 1 day or lon- 

 ger, while heights exceeded 0.5 m only 18 times for this same duration. This 

 change in durations occurred because the longer durations of lower waves may 

 be interspersed with shorter, but more frequent, intervals of higher waves. For 

 example, one of the times that the wave heights exceeded 0.5 m for 16 days 

 may have represented three times the height exceeded 1 m for shorter 

 durations. 



Spectra 



Monthly spectra for the offshore Waverider buoy (Gauge 630) are present- 

 ed in Figure B8. The plots show "relative" energy density as a function of 

 wave frequency. These figures summarize the large number of spectra for each 



82 



Appendix B Wave Data for Gauge 630 



