NO. 4 TEMPERATURE VARIATIONS IN THE NORTH ATLANTIC 2/1 



a negative correlation, i. e., decrease of temperature follows increase 

 of solar radiation. He came to the conclusion that the stations with 

 positive correlation are distributed along certain belts round the 

 earth : one belt in the tropic regions and two others in the arctic 

 and antarctic regions. Between these belts there are two other belts 

 with negative correlation, corresponding chiefly to the temperate 

 zones and partly to the sub-tropical zones. In the belts with positive 

 correlation the maximum temperatures follow about one or two 

 days after the maximum of solar radiation. In the zones with nega- 

 tive correlation the maximum effect of the changes in the solar 

 radiation follows after three or four days. 



By computing the consecutive five-day means of the daily values 

 Dr. Clayton has plotted smoothed curves of the solar constant and 

 of the temperature at several meteorological stations, for the months 

 September to November, 191 3. The temperature curves show great 

 resemblance to the curve of the solar constant. At five stations, 

 where the correlation was positive, there is a direct agreement be- 

 tween the temperature curves and the solar curve. At two other 

 stations, where there was a negative correlation, the temperature 

 curves are inverted. But in some cases, especially at Stykkisholm, 

 Iceland, and Sacramento, California, the temperature curves show 

 direct agreement with the solar curve for some part of the period 

 investigated ; but then suddenly the agreement changes to be inverted 

 or vice versa. As will be seen, this is a phenomenon which cor- 

 responds in a remarkable way to the relations we have found to exist 

 between the temperature curves for a great many stations and the 

 sun spot curve, during long periods. We found, for instance, 

 that the consecutive twelve-month means of the temperature at dif- 

 ferent stations could, during a long series of years, vary directly 

 as the sun spot numbers, but then they suddenly changed, and 

 during a subsequent long series of years they varied inversely as 

 the sun spot numbers, or vice versa. We also found that in some 

 regions of the earth the temperature curves varied generally di- 

 rectly as the sun spot numbers, while in other regions of the world 

 the temperature curves varied inversely as the sun spot numbers ; 

 and finally in some regions the temperature curves were mixtures 

 of these two types of curves. The temperature varied partly directly, 

 and partly inversely as the sun spot numbers. Dr. Clayton's curves 

 of the five-day means of temperature at various stations seem to 

 indicate that there is exactly the same difference of type between 

 these curves as compared with the curve of the five-day means of the 

 solar radiation. 



