MELLEN: SOUND PROPAGATION IN A RANDOM MEDIUM 



ing to that accuracy? 



Dr. Mellen: Absolutely. 



Dr. Goodman: That's curious, because I don't. 



Mr. P. H. Lindop (Admiralty Research Laboratory) : We have some 

 unpublished results for sound channels in the Western Mediterranean, 

 Eastern North Atlantic, and the Southern Nojrweg-ian Sea. Looking at 

 these rough results we don't see anything anomalous. We take out 

 cylindrical spreading and we don't see anything of the order that 

 you have seen. 



Dr. Mellen: In the Mediterranean? 



Mr. Lindop: In the Western Mediterranean and the Eastern North 

 Atlantic. 



Dr. Mellen: I'm not quite sure where these results came from. 

 These were taken from Bill Thorp's notes, and were part of the JOAST 

 experiment. Two areas, one in the Tyrrhenian Sea and the other east of 

 Malta, were both measured. Now, if this was east of Malta, there is a 

 very strong ocean front which could be responsible for the relatively 

 large amounts of scatter that were observed. 



Mr. Charles W. Spofford (Office of Naval Research) : In the Hudson 

 Bay and Baffin Bay, were you using 1/3-octave filtering? 



Dr. Mellen: Yes. All the experiments are 1/3-octave filters. 

 We haven't progressed to the sophistication of FFT. 



Mr. Spofford: Have you taken your mode model or FFP and run it 

 to simulate the 1/3-octave filter to convince yourself that the spread- 

 ing is cyclindrical when viewed through the 1/3-octave filters? 



Dr. Mellen: Dave Browning is going to talk about that tomorrow. 



Dr. F. D. Tappert (Courant Institute of Mathematical Sciences, 

 New York University) : Your shallow-water results have been criticized. 



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