PAPER BY PROF. OBERBECK. 



167 



VII. NUMERICAL EXAMPLE FOR A CYCLONE: NOTE ON ANTICYCLONES. 



In order to show the applicability of the formulae -obtained in the last 

 section to cyclones as they actually occur in nature, I have executed 

 the following' computation of a numerical example: 



In this computation I have assumed 



X = 0.00012 



This value corresponds to an average latitude of 55.5°. For Jc I have 

 assumed the same value, whereby the value obtained for the influence 

 of friction is rather large. 



For the complete determination of the system of winds the constant 

 c of the ascending current of air and the dimensions of the inner region 

 must also be known. We can obtain this in various ways. We can 

 assume as given, a definite difference in pressure between the center 

 and a circle of known radius ; or on the other hand, we can assume 

 that the velocity of the wind is known at a certain distance from the 

 center. I have chosen the last assumption. 



The wind system may therefore be characterized by the assumption 

 that at a distance of 1000 kilometres from the center the wind velocity 

 shall be 10 metres per second. 



According to equation (29) when we put A=A- we have 



c A'- 1 



go = 



v 2 



If in this we put go = 10 metres and r = 1000000 metres we then 

 have c E 2 = 10000000 -v/> • Since furthermore c< A, therefore the same 

 equation shows that we must have B > 343.3 kilometres. 



In the selection of appropriate values of c and B, another circum- 

 stance is to be considered. The discussion of the formula? (30) for the 

 velocity go shows that under the assumption here made of A = A-, the 

 maximum velocity of the wind occurs at the boundary of the two 

 regions. The smaller the inner region is chosen, by so much larger 

 results the maximum velocity oo K . In the following table some coor- 

 dinate values c, //, B, and go r are given. 



Table I. 



