KELLEN: SOUND PROPAGATION IN A RANDOM MEDIUM 



Dr. Mellen: From your data, presented last night, I made an 

 estimate it would be not measurable. 



Dr. Flatte: You mean because of the range? 



Dr. Mellen: No, because of the large scale size of the internal 

 waves. In other words, I think we're dealing with a smaller scale size 

 which increases the scattering loss. 



Dr. Flatte: If you really have to go down 15 meters, then you're 

 right. Internal waves will not explain it. 



Dr. Mellen: It isn't that far off though, because even though 

 your scale size for the horizontal is much larger, your vertical 

 scale size is smaller because of the ellipticity in the internal 

 wave inhomogeneity. 



Dr. Flatte: The vertical scale size is what I'm talking about. 

 The vertical scale size in the internal waves is like 200 meters. 



Dr. Mellen: The scattering will depend upon the diffusion 



constant which goes as y /a (see Figure 14) in the geometrical 



o 



acoustics limit. But if these inhomogeneities are not spherical as 

 we said, then they are multiplied by the ratio of the horizontal major 

 axis to the vertical minor axis. You get that much more diffusion if 

 the things are lenticular. 



Dr. Flatte: Then we're going to multiply your 15 meters by a 

 factor of approximately 10 to account for the ellipticity, which 

 makes it very close to internal waves. 



Dr. Mellen: Right. Yes. 



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