NO. 8 



liAROMIiTKU PRESSURF. — DLEfL AN'l) DUKLL 



+ 1.8 ml), has shifted sonicwhal toward the S., and is now situated 

 over the middle part of Scandinavia. Remaining parts of the minus- 

 area (with — 0.9 and — 0.7 mb.) are only just slightly discernible. The 

 maximum gradient has been reduced to 2.7 mb. P'igure 13, 7 days 

 after, begins to show an approach to the neutral initial state. Any 

 noteworthy gradient can no longer be recognized there. The greatest 

 difTerencc bctwocn positive and negative departures of the pressure 



12 mb 



Avoroge Departures of 



Sea-Level Pressure -Held from Long -Period Meon$ (in mb ) os 



related to oil ( 320 ) those Days when the Ionosphere wo* 



particularly Disturbed 



One Day Before 



WlnHrmonim of '«• 16 YtO'l wtth lev S»l> - *elKrll|r (r|40)«» lh« Pttl»« l»04-l»3T 



Fu.. 5. 



from the normal distribution amounts to 1.8 mb. Finally, in figure 14, 

 8 days after, gradients no longer exist — only a completely irregular 

 and insignificant distribution of very flat positive and negative pressure 

 anomalies. The maximum dilTercncc between them is not greater 

 than 1.4 mb. This is nearly the same value as on the days before 

 the disturbed days, at the beginning of the whole development. In 

 just the same manner as there, the picture is dominated by a zero 

 isoline, which, in the form of an unbroken curve, covers a great part 

 of Europe. Figure 15 represents the average behavior of the max- 



