METHODS 



The noise data originated from four hydrophones located at 

 depths greater than 500 fathoms. The four hydrophone stations 

 were selected to sample the Pacific coastal area from Washington 

 to Southern California. They are designated A, B, C, and D in 

 order from north to south. The larger part of the analysis was 

 done on station A, which provided ambient -noise data with a nom- 

 inal amount of contamination by ship and general transients, and 

 had larger fluctuation in wave height at large distances from the 

 hydrophone . 



Data on wave height 4 ' 5 were supplied by the Fleet Numerical 

 Weather Facility, U. S. Naval Postgraduate School, Monterey, 

 California, in the form of contour charts of wave height in 3-foot 

 intervals for the general areas of interest (fig. 3). 



Figure 3. Portion of wind-wave analysis for 0600 GMT 01 October 1964 from Fleet 

 Numerical Weather Facility, Monterey, California, showing wave-height contours. 

 Contour interval is 3 feet. 



