trial.* On the l^th the observed wave direction agreed quite well with the mean 

 wave direction of the dominant frequency as measured by the Wave-Track. On the 

 15th, the Wave-Track buoy's indicated mean direction of the dominant frequency con- 

 tinued to vary about the mean value of 200 degrees, while the observed direction 

 shifted to 165 to 180 degrees. The mean wave direction of the dominant frequency 

 for the Wave-Track buoy on the l8th, varied significantly from run to run. While 

 recording the data for Run 35, it was noticed that the signals from the direction 

 channels had drifted out of the linear recording range of the analog tape recorder. 

 The direction channels coming out of the receiver were then zeroed, but a few pre- 

 vious runs may also have been affected. 



The directions measured by the WAVEC and Wave-Track buoys differ throughout 

 the trial. However, shifts of the mean wave directions of the dominant frequency 

 between the two buoys generally agree in time and in the direction of the shift. 

 This may indicate a relative offset between the two buoys' magnetic recordings or 

 coordinate resolution. 



The energy densities, as measured by both buoys, agree well, with a few minor 

 exceptions. The spectral shapes are similar, but in several cases the density 

 peaks of the WAVEC data are noticeably greater than the Wave-Track data. The data 

 analyzed by DHI produced a greater frequency resolution than for the Wave-Track 

 buoy data analyzed by DTNSRDC. The data from the WAVEC buoy shows higher, sharper 

 peaks while the Wave-Track buoy data shows broader peaks. When two or more sharp 

 peaks close together are produced by the analysis with greater resolution, the 

 other analysis may combine them into one or two shorter broad peaks. Overall the 

 total energy measured by both buoys is about the same for each run. 



As mentioned earlier, the data segments in the DTNSRDC analysis are overlapped 

 by 50 percent to smooth the results. The DHI analysis averages the spectral den- 

 sities in 0.05 hertz bandwidth for each frequency center. Confidence limits are 

 generally narrower when less resolution is required, given similar data lengths and 

 sample rates. 



The mean wave directions between the two buoys generally agree for frequencies 

 above 0.11 hertz. A correction for the magnetic declination of 13 degrees west has 

 been applied to the mean directions of the Wave-Track buoy data. This may account 



*The direction of the dominant frequency is likely to be the direction most 

 easily observed. 



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