during the propagation tests, ' These are shown in Figures 24, 25, 

 26, and 27. The velocity-depth profiles of Figure 24 were taken at the 

 locations shown in Figure 25. From both a theoretical and experimental 

 sound transmission viewpoint, this section of the Straits of Florida 

 presents the following interesting features: 



1. A somewhat uncertain surface channel. 



2. A themocline that progressively deepens from west to east. 



3. A downward refracting medium below the thermocline. 



4. A two section bottom profile comprising a half depth and 



a full depth section. 



5. The possibility of internal waves along the thermocline. 



It is hoped that it will be possible to study propagation across 

 the Straits in relation to oceanographic parameters, on a continuous basis. 

 This will require a sound source on the west bank roughly equivalent to 

 a half pound charge, and means on both the west and east banks to continu- 

 ously measure temperature versus depth and surface wave height. Measurements 

 on a continuous basis through diurnal, seasonal and weather cycles will 

 provide a type of information that has not been available before, for evaluat- 

 ing theoretical procedures. 



The Marine Laboratory 

 Institute of Marine Science 

 University of Miami 

 June 26, 1961 





Bottom Profiles, Miami to Bimini, Memorandum for File, May 29, 1961, 

 John Schenck 



^ Sound Velocity versus Depth Profiles, Florida Straits, Memorandum 

 for File, June 13, 1961, John Schenck 



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