MARTIN/PERRONE : GEOGRAPHICAL VARIATION OF AMBIENT NOISE IN THE OCEAN 

 FOR THE FREQUENCY RANGE FROM 1 HERTZ TO 5 KILOHERTZ 



REFERENCES 



Perrone, A. J., "Deep-Ocean Ambient-Noise Spectra in the Northwest 

 Atlantic," J. Acoust. Soc. Am. 46:762-770, 1969. 



Wenz, G. M. , "Acoustic Ambient Noise in the Ocean," J. Acoust. Soc. 

 Am. 54:1936-1956, 1962. 



DISCUSSION 



Dr. G. Raisbeck (Arthur D. Little, Inc.): In Figure 4 you showed 

 what appeared to be a negative correlation between wind velocity and 

 noise level, and I wondered if it isn't a typographical error in the 

 displacement of the zero. 



Dr. P. W. Smith (Bolt, Beranek, and Newman, Inc.): No. You've 

 never been to sea. 



Mr. R. L. Martin (New London Laboratory, Naval Underwater Systems 

 Center) : All I can say, Toby, is that it was not a long time series, 

 and we could very well have had this type of offset where we got a 

 slight negative correlation. But I think the figure is correct. I 

 have noticed this before, but I have not ever recalculated it. 



Dr. D. Ross (Tetra Tech, Inc.) : This effect was observed by 

 Woods Hole people in 1948 during a gale off Nantucket. We called it 

 the "Coast Guard effect." It has to do with the fact that when the 

 sea' gets very rough, ships slow down. You would expect less noise 

 from shipping when you have a very high sea state giving you a slight 

 negative correlation of the low frequency noise with sea state. Plus 

 the fact that the surface itself gets very rough which gives you some 

 scattering, so it may be that your propagation actually changes also. 



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