754 



cox 



[CHAP. 22 



\,0 1.5 2.0 



CYCLES PER HOUR 



0.1 0.2 0.3 04 0.5 0.6 



O.OI Q 



0.1 0.2 0.3 0.4 0.5 0.6 



CYCLES PER HOUR 



Fig. 23. Spectra and coherences of temperature oscillations off Bermuda according to 

 Haurwitz, Stommel and Munk (1959). Upper panel shows results of analyses for high 

 frequencies, lower panel for low frequencies. Scales for spectra are on left side for oscilla- 

 tions at 50 m depth and right side for 500 m. Arrows indicate the magnitude within 

 which 95% of statistical variations due to limited lengths of record should fall. R^ is 

 the square of the coherence between temperature oscillations at the two depths. 

 Horizontal lines on the same graph show approximate level below which 95% of 

 estimates of R^ will fall if the temperature oscillations are not coherent. The six 

 analyses were made for temperatures recorded between Nov., 1955, and Feb., 1956, 

 as follows : 



A:l 9 NOV.-28 Nov. A:4 



A:2 28 Nov.- 18 Dec. B:l 



A : 3 18 Dec.-7 Jan. B : 2 



1 1 Nov.-5 Jan 

 11 Jan.-2 Feb. 

 13 Jan.-31 Jan. 



