Wolff, Tatro, and Megehee 



therrnocline gradients varying from 1°F per 100 feet to 10°F per 100 

 feet (Figure 10). As before, the convergence zone ranges were 

 converted to equivalent temperature changes and plotted (Figure 11). 



Finally, the 400 m temperature was varied over a range from 5°C 

 to 12°C while holding all other parameters constant. Figure 12 shows 

 the profiles; these were run through the ray trace program, converted 

 to equivalent temperature changes and plotted (Figure 13). 



As a last step, the parameters were varied in pairs to check the 

 interactions. The warmest and coldest sea surface temperatures were 

 run with the shallowest and deepest layer depths, etc. All results 

 were converted to equivalent temperature changes and compared with 

 existing plots. In all cases they agreed quite well. 



With these relationships established, it is possible to predict 

 convergence zone range if the four critical parameters are known. It 

 is necessary only to add the three temperature corrections to the sea 

 surface temperature to obtain an adjusted temperature: 



T(ADJ) = SST + AT(MLD) + AT (^T) + AT(T400) 



and use this adjusted temperature to enter the Temperature versus 

 Range plot. 



VERIFICATION 



To determine the accuracy of the prediction system , twenty 

 measured temperature and salinity profiles, half from the Atlantic and 

 half from the Pacific , were run through the ray trace program , and the 

 convergence zone ranges obtained were compared with the ranges 

 predicted using the series of graphs. For these 20 runs the largest 

 error found was 1,1 nautical miles, and the mean error was 0.5 

 nautical miles. The prediction system tended to predict longer 

 ranges than the ray trace showed. This is certainly due at least in 

 part to the assumption of a constant 35 parts per thousand salinity 

 which was made in determining the effects of the parameters. Lower 

 salinities, at the surface which are generally the case, would result 

 in lower surface sound velocities and shorter convergence zone 

 ranges, 



APPLICABILITY AND LIMITATIONS 



The prediction scheme as derived seems to be equally 

 applicable in the Atlantic and the Pacific Oceans, It fails 



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