SPINDEL: PHASE FLUCTUATIONS, COHERENCE AND INTERNAL WAVES 



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Spindel, R. C, R. J. Porter, and R. J. Jaffee, "Long Range Sound 

 Fluctuations with Drifting Hydrophones," J. Acoust. Soc. Am. 56, 

 440-446, 1974. 



Stanford, G. , "Low Frequency Fluctuations of a CW Signal in the Ocean," 

 J. Acoust. Soc. Am. 55, 968-977, 1974. 



Steinberg, J. C. , et al., "Transmission Fluctuations," Institute for 

 Acoustical Research, Miami Division, Palisades Geophysical 

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Weinberg, N. L. , J. G. Clark, and R. P. Flanagan, "Internal Tidal 

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DISCUSSION 



Dr. S. M. Flatte (University of California College at Santa Cruz) : 

 I think there is a difficulty in the way you treated the effect of 

 internal waves on the phase fluctuations. Before I describe the 

 difficulty, let me say that I believe that treating it properly 

 will not change your qualitative result, with which I agree wholes 

 heartedly — that is, that internal waves cause the type of fluctua- 

 tions we are observing. But I think it will change the quantitative 

 comparisons . 



If you take a source and a receiver which are connected by a path 

 such as shown in Figure 8, then the question is: What is the region 

 of this path where the internal waves make the biggest effect? 



You suggested that there was a fixed depth. The fluctuation 



2 

 formula which you gave (in Figure 10) for F^ (w ) varied as 1/sin (f) 



g g 



where is the angle the ray makes with respect to the internal wave 



448 



