NO. 7 



THE ATMOSPHERE AND THE SUN CLAYTON 



II 



tribution of pressure with latitude is shown by a continuous line. 

 The dotted Hne shows the distril)Ution with high solar activity. With 

 high solar activity the equatorial low pressure belt and the high pres- 

 sure belts in middle latitudes are both intensified and the polar 

 anticyclone diminished. This clearly means an intensification of the 



Fig. 7.— Differences in pressure with change from low to high solar activity. 



Shaded area shows increased pressure, unshaded areas decreased pressure. 



(Difference between yearly means in tables 3 and 4.) 



nomial atmospheric circulation. The decrease in the polar anticy- 

 clone is attributed to the increased circulation around the pole, the 

 centrifugal action developed in the circulating winds causing a fall of 

 pressure in the polar basin. The efifect of tbe earth's rotation on the 

 wind increases with latitude, and for this reason the fall of pressure 

 in the equatorial belt is greater at latitude 20° than at the Equator. 

 (See fig. 5.) The broken line shows the distribution of pressure with 



