PART IV: WAVE AND WATER-LEVEL DATA 

 Wave Height and Period 



49. The wave heights plotted in Appendix D and tabularized in Appendix E 

 were collected as part of the routine collection program of the FRF Measure- 

 ments and Analysis work unit. Details of the collection of this data are 

 available in the FRF Annual Data Summaries (Miller 1984; Miller et al. 1985, 

 1986). The data from a number of gages are sampled at 4 Hz , every 6 hr 

 (hourly during storms) for 20 min. The energy-based significant wave height 

 H m Q is computed as four times the standard deviation of the 20-min record. 

 The wave period is computed as period associated with the peak of the wave 

 spectra . 



50. To provide as complete a record as possible, data from two gages 

 have been combined. The majority of the record is from Gage 625, a Baylor 

 wave staff gage located at the seaward end of the pier. When this gage was 

 inoperative, data from Gage 620, a Waverider buoy located directly off the 

 pier end in 18 m of water, were transformed to the pier end location using the 

 the method of Hallermeier (1983). This method considers frictional dissipa- 

 tion and was developed using data from the FRF. 



51. During large storms, Gage 625 was in the surf zone and wave heights 

 were saturated, i.e., limited by wave breaking. The maximum wave height limit 

 depends on water level but is usually under 3 m. The maximum recorded wave 

 height of 3.5 m occurred during a storm in November 1981 that coincided with 

 abnormally high spring tides. 



52. The tables in Appendix E contain daily measurements of wave height 

 and period for wave heights under 2 m and measurements every 6 hr for waves 

 over 2 m. 



53. More detailed wave information, including wave spectra and data from 

 other gages, is available through the CERC Coastal Engineering Information and 

 Analysis Center (CEIAC). 



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