144 



JOHN S. BARLOW 



1.0 - 



t^ 0.8 - 



20 30 40 50 60 



GEOGRAPHIC LATITUDE 



1.0 - 



?: 0.8 - 



o'-r 



30 40 50 60 



GEOGRAPHIC LATITUDE 



Fig. 12. Relative concentration of Strontium-90 versus geographical latitude. 



a. In the stratosphere, averaged over the period November 1957-November 1958. 

 1.0 = 12 mc per square mile. (Data from Feely, 1960). 



b. On the ground in November, 1958. 1.0 = 4.1 mc per square mile. (Redrawm 

 from Wexler, 1960.) 



parameters are based on the assumption of a one-to-one {i.e., linear) corre- 

 spondence between the exposure and the number of cases of the disease. 

 Should a nonlinear relationship obtain, it theoretically would be possible 

 for a more pronounced latitude distribution for the disease to result from a 

 cosmic ray phenomenon of a given latitude distribution. (The altitude effect 



