PART III: WAVES 
27. This section presents summaries of the wave data. A discussion of 
individual major storms is given in Part IX and contains additional wave data 
for times when wave heights exceeded 2 m at the seaward end of the FRF pier. 
Appendixes B through E provide more extensive data summaries for each gage, 
including height and period distributions, wave direction distributions, 
persistence tables, and spectra during storms. 
28. Wave directions (similar to wind directions) at the FRF are season- 
ally distributed. Waves approach most frequently from north of the pier in 
the fall and winter and south of the pier in the summer, with the exception of 
storm waves that approach twice as frequently from north of the pier. 
Annually, waves are approximately evenly distributed between north and south 
(resultant wave direction being almost shore-normal). 
Measurement Instruments 
29. The wave gages included two wave staff gages (Gages 645 and 625), 
one buoy gage (Gage 630), and one pressure gage (Gage 111) as shown in 
Figure 2 and located as follows: 
Distance Offshore Water Depth Operational 
Gage Type/Number from Baseline m Period 
Continuous wire (645) 238 m 3.5 11/84-12/91 
Continuous wire (625) 567 m 8 11/78-12/91 
Accelerometer buoy (630) 6 km 18 11/78-12/91 
Pressure gage (111) 1 km 9 09/86-12/91 
Staff gages 
30. Two Baylor Company (Houston, TX) parallel cable inductance wave 
gages (Gage 645 at sta 7+80 and Gage 625 at sta 19+00 (Figure 2)) were mounted 
on the FRF pier. Rugged and reliable, these gages require little maintenance 
except to keep tension on the cables and to remove any material that may cause 
an electrical short between them. They were calibrated prior to installation 
by creating an electrical short between the two cables at known distances 
along the cable and recording the voltage output. Electronic signal 
conditioning amplifiers are used to ensure that the output signals from the 
gages are within a O- to 5-V range. Manufacturer—stated gage accuracy is 
about 1.0 percent, with a 0.1—percent full-scale resolution; full scale is 
14 m for Gage 625 and 8.2 m for Gage 645. These gages are susceptible to 
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