PART IV: WAVE AND WATER LEVEL DATA 



18. Wave heights and periods have been collected at the FRF on a con- 

 tinuous basis at various gages. Gage 625, a Baylor wave staff located near 

 the end of the research pier (Figure 2), was used in this study, since it had 

 the most complete data during the study period. Data were sampled at 4 Hz, 

 every 6 hr for 20 min, with hourly readings during storms (Howd and Birkemeier 

 1987). During some storms, Gage 625 was in the breaker zone and gave breaking 

 wave readings. During these times and when the gage was otherwise inoperable, 

 data were transformed into the pier from Gage 620, a Waverider buoy located in 

 18 m of water, some 2 . 1 km eastward from the baseline on the dune, directly in 

 line with the pier (Birkemeier et al . 1985). These data were transformed into 

 the depth of the pier using a method developed by Hallermeier (1983) . 



19. A tide gage maintained by the National Oceanographic and Atmo- 

 spheric Administration, National Ocean Service (NOAA/NOS) , at the seaward end 

 of the pier (Figure 2) recorded the water levels due to tidal fluctuations and 

 storm surge. The total water level was used to give an identification of 

 storm surge as a forcing function to profile and sediment change. 



20. Figure 6 shows the time-averaged record of the wave height and 

 water level relative to the profile surveys and sediment sampling. The sea- 

 sonal cycle in wave height can be seen with low waves occurring during the 

 summer months of June through August. Only one event of higher waves (just 

 reaching 2-m heights) occurred 2-3 August 1985. Higher frequencies of extreme 

 events (waves greater than 2 m and elevation of water level above normal tidal 

 variations) occurred during the fall, winter, and spring months of 1984 and 

 1985. Approximately one event occurred within each fall, winter, and spring 

 monthly period during the study. Several times during the study, the wave 

 height was greater than 2 m. Some of these events were accompanied with ele- 

 vated water levels, indicative of a storm surge. The highest waves recorded 

 during the study were greater than 3 m and occurred from 11 to 17 October 

 1984. Otherwise, the entire study period from March 1984 to September 1985 

 was relatively free from major storm events. 



21. In an effort to identify high wave events that would affect profile 

 change and sediment distribution, wave power was calculated and plotted for 

 the study period (Figure 7) . The wave power was calculated from the wave 



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