Isaacs 



quadrant. Keeping in mind the fact that these data are monthly and 

 surface temperature only, the best explanation for this behavior is 

 that there exists an anisotropy between the heating and cooling pro- 

 cesses. Undoubtedly this results from the production of a thin 

 stable surface layer in anomalous heating, which represents a 

 relatively low total thermal change. Anomalous cooling, on the other 

 hand, must involve instability and convection, requiring a much 

 larger thermal change. Thus anomalous heating is a rapid process 

 and anomalous cooling a slow process. In our study on monthly 

 changes we often catch the cooling in mid-step but the anomalous 

 heating takes place so rapidly that it is most often complete within 

 the monthly time scale. 



These two examples will serve to present the type of con- 

 straints and insights that our pilot study is providing. 



I will now discuss the field program from which we hope to 

 derive a much fuller understanding of these large-scale temperature 

 fluctuations . 



The principal tool that will be employed is the small deep- 

 moored instrument station that has been under development for many 

 years at Scripps. These deep-moored stations were first attempted in 

 the Pacific Proving Grounds at the IVY event in 1951, and later 

 deployed in larger numbers in subsequent tests for the recording of 

 fallout and other weapons effects. Figure 8 shows a typical deploy- 

 ment in that period. These moorings were very successful. Depths 

 of mooring were from 7OO fathoms to greater than 3000 fathoms. 



Later developments allowed a greater penetration of 

 sensors, and our recent models record to depths of 3000 feet and are 

 showing a very satisfactory life. Catamarans as shown in Figure 9, 

 have all remained moored and operating in the open North Pacific for 

 six months or more, and one survived for over two years. Two 

 moorings placed in the equatorial Pacific two and a half months ago 

 have just been reported to be operating and in good shape. 



We thus have a number of the long deep-sea records of 

 temperature versus depth. Figure 10 shows a spectral analysis of 

 temperature depth fluctuations of a 100 day record taken about 600 

 miles off the California coast. In this record an incoherent lunar 

 semi-diurnal fluctuation is the greatest. Curiously, the lunar and 

 solar frequency are not significant but there is a strong unexplained 

 coherent semi-solar periodicity. I show this analysis to point out 

 that the moored stations are capable of yielding data that is 

 amenable to spectral analysis and the determination of the periodi- 

 cities involved in temperature-depth fluctuations. 



Another essential test of these data is to determine 

 whether they are comparable to the ships' data from which the Bureau 

 of Commercial Fisheries has derived the delineation of the anomalous 



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