RECOMMENDATIONS 



1 . Continue development of the thermistor chain to improve 

 the quality, accuracy, and reliability of oceanographic data. 



2. Investigate the use of additional sensors (in conjunction 

 with temperature) on the thermistor chain for measuring current, 

 turbidity, sound velocity, and salinity. 



3. Study, by means of the thermistor chain, the nature of 

 internal waves and the effects on thermoclines of islands, shoals, 

 coastal configurations, tides, known currents, upwelling, water- 

 mass boundaries, storms, and seasons. 



4. Determine, by use of the thermistor chain and partially 

 known sea temperature structures, the most persistent oceanic 

 regions of smooth, normal, rough, and irregular thermoclines, 

 and study the effects of such structures on sound transmission. 



SUMMARY AND CONCLUSIONS 



The two-dimensional investigation with the thermistor 

 chain of 27 sections of temperature structure off Baja California 

 provides new detailed data on the upper layers of the sea and 

 makes it possible to determine the processes of differential 

 water motion, turbulence, and apparent Doppler effect. 



The isotherm slope at two levels in the 27 locations re- 

 vealed that the median value generally became steeper when the 

 towing was to the north or south, which implies an east-west 

 orientation of wave-like fluctuations in the thermocline. Similarly, 

 the deeper of the two isotherms, selected where the vertical 

 temperature gradient was weak, had more larger vertical angles 

 than did the shallower one. A wavelength between 1400-2400 feet 

 is common for thermocline oscillations. This corresponds to a 

 frequency of 2^-4 minutes, or near the Vaisala frequency. 



The autocorrelation of successive depth values of given 

 isotherms decreased more rapidly when the towing was to the 

 east or west. The power spectrum of isotherm depth showed 

 peaks at varying frequencies. The higher, more significant 

 peaks appear to be most numerous in the zone marked by an 



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