SPINDEL: PHASE FLUCTUATIONS, COHERENCE AND INTERNAL WAVES 



Dr. Clark: Over what? 



Mr. Spofford: Over the fraction of a mile. There is a ripple 

 on the order of a cycle in phase. 



Dr. Clark: You took a linear phase trail out of this? 



Mr. Spofford: 1 went back and looked at half-mile regions, 

 removing the linear trend, and still ended up with residual fluctu- 

 ations of about a cycle in phase extrapolated to 400 Hz. 



Dr. Clark: You made a comment on that last slide that you did 

 not see any reason for a phase flip in the deep fade. Is that right? 



Mr. Spofford: No, I did not say that. I said the phase flip 

 is continuous in the model at least. Such physics does not have 

 discontinuous phase. The problem is, it is always at these nulls in 

 transmission where you are probably looking at noise. 



Dr. Clark: Right. 



Dr. M. Schulkin (Naval Oceanographic Office) : One remark on 

 the last slide that Dr. DeFerrarri showed. Were those Doppler shifts 

 measured? 



Dr. DeFerrari : No. 



Dr. Schulkin: Was it just coincidence that you chose 8 seconds? 



Dr. DeFerrari: I started at 8 and then on down. 



Dr. Schulkin: They are as close to sinusoidal effects as you 

 are going to get in the ocean. You are apt to pick up an 8-second 

 swell by measurement, and I just wondered if you did. 



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