Uncertainty in peak period is affected more by resolution than measurement error. 

 Peak period is the inverse of the center of the frequency band with the most total energy. 

 This band, whose width is set by the analysis procedure, effectively averages energy from 

 multiple discrete frequencies; and the true peak period could lie anywhere within that band. 

 Conceivably, the spectrum could contain another discrete peak within another band that 

 approaches, or even exceeds, the energy of any discrete frequency in the peak period band. 

 Small variations in the values of these energies from hour to hour sometimes cause rapid 

 changes in the reported peak period, particularly at low wave heights. 



Examples of these wave data are given in Chapter 3. Table 2 shows the months for 

 which the wave gauges were operational. Files containing these wave data are avail- 

 able on the World Wide Web at (http://sandbar.cerc.wes.anny.mil/). Directional (2-D) 

 wave spectral plots, which are not included in the examples shown in Chapter 3 or on the 

 World Wide Web site, can also be obtained from the archived raw data. 



Table 2 



Wave Data Availability 





Jan 



Feb 



Mar 



Apr 



May 



Jun 



Jul 



Aug 



Sep 



Oct 



Nov 



Dec 



1995 



DWG1INT1 

 Offshore 





















X 



X 



X 



DWG1EBB1 

 Ebb Shoal 





















X 



X 



X 



DWG10TH1 

 Inlet Throat 





















X 



X 



X 



1996 



DWG1INT1 

 Offshore 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



DWG1EBB1 

 Ebb Shoal 



X 



X 



X 





X 



X 



X 



X 



X 



X 



X 



X 



DWG10TH1 

 Inlet Throat 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



X 



1997 



DWG1INT1 

 Offshore 



X 



X 



X 



X 



















DWG1EBB1 

 Ebb Shoal 



X 



X 



X 



X 





X 



X 



X 



X 



X 







DWG10TH1 

 Inlet Throat 



























X indicates that a full or partial data set Is available for that month. 



Water Level Measurements 



Water level was measured at four locations inside the inlet as shown in Figure 3. At 

 three of these measurement stations (Sites E, F, and G), Paros pressure sensors were 

 deployed; the same type of sensors as were used in the wave gauges. Each gauge was 

 housed in a protective steel sleeve and attached to a piling. The fourth water level gauge 

 was located at the Coast Guard Station just inside the inlet entrance (Site D). This gauge 



Chapter 2 Instrumentation and Procedures 



