Fig. 



-Comparison of monthly frequency of 

 Aurora 



CENTCRY 



VII 



¥ 



vm IX 



X X! 



XII 



XIII x\v 



XV 



X^l XYl! 



ttt: 



XIX 



XX 



WARM 



Of\Pi 



7/ 



//'// 



'/' 



//// 



/// 





COLD 



WARM 



V 





COLO 



///;;rOOYEAR PERIODIC H A '/<//// k/v /' > T/^-/' ',// V' -^ 



'/ ^'/change ofcumate ^X///y\Vh'/ '/'///^^' ////^/^/^ /•/ 



'/'//o IN JAPAN //V^/:^'';.>d/>//^vf'^l5^^^t|'5HIOKA/ 



Pig. 3. — Frequency of Aurora in Japan and Korea 



121 



