NO. 8 



BAROMETRIC PRESSURE — DUEF.L AND DUELL 



are shown in figure 2. The niaxinium difTerence on the third to fourth 

 day after the key dates amounts to 2.6 to 3.2 mb., varying according 

 to the geographical position of the station. Additional evidence for 

 the reality of the relationship is found if these statistics are subdi- 

 vided arbitrarily according to even and odd years or according to 

 other points of view. Curves representing these completely indepen- 

 dent arrangements of the different parts are extremely similar. This 

 is true tor all stations which were examined. For want of space, 

 however, only one exanijjle is presented in figure 3. 



I020|- 

 1019- 

 lOIS - 

 1017 

 CI6 - 

 1015 ■ 

 1014- 



Oe Bilt 



Prtsdom 





Vienna 



Breslou 



Korisruhe ! 



sy — 



The Averdqe Behoviour of Seo- Level Pressure os rdoled to oil m, 

 ( 320) those Doys when the Ionosphere was porticulorly 1*^* 



Disturbed (— )and to oii (320 ) ttiose Doys when the lonospherE 

 wos porticulorly Undisturbed (—^ 



WlftttrmoAVn of tt>« ■& Y»ort mAh to 

 Sun- Acl>«itr (rt40)olm« Ptria4 

 1906 - 1937 



, Lemberg 



•020 



«■• 



>0i8 



• IOI7 



lOlC 

 iOi» 

 IOI4 



iOl» 



To find out more about the kind of relationship between the state 

 of the ionosi)here and the behavior of sea-level pressure, the number 

 of stations to l)e included in this investigation was increased to 26. 

 As far as the respective data were available for such a long series 

 of years, the stations were selected in such a manner that the final 

 results could be represented synoptically. The following stations 

 could be used for that purpose: (from X. to .S.) Vardoc, Ilajiaranda, 

 Stykkisholm, Trondhjem, Lerwick, Oslo, Leningrad, Stockholm, Mos- 

 cow, Copenhagen, Konigsberg, Potsdam, \'alentia, De Bilt. Warsaw, 

 Breslau, Kiev, Lemberg, Karlsruhe, Brest, \*icnna, Bucharest, 

 LaCoruna, Marseille, Sofia, and Rome. I'igure 4 shows the average 

 normal sea-level pressure distribution (mb.) over Europe during the 



