28 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 10 



of short radio waves, known as "Moegel-Dellinger effect" ; and, 

 finally, an increase in the number and intensity of a certain kind of 

 static in the range of very long radio waves (A'~ 10,000 m.), and 

 likewise a considerable reinforcement of the so-called "solar noise" 

 in the range of ultrashort- and decimeter-waves. The influence of 

 these ultraviolet invasions is possible only on the sunlit earth 

 hemisphere. 



During the absorption of ultraviolet photons in the high atmos- 

 pheric layers, their energy produces ionization, dissociation, especially 

 of the molecular oxygen, heating and formation of certain chemical 

 compounds, partly in the form of condensation nuclei. Furthermore 

 there can be expected, according to L. Vegard (32), an electric 

 polarization of the ionosphere during the ultraviolet irradiation be- 

 cause of the photoelectric expulsion of high-energy negatrons which 

 move upward and reach considerable heights. Possible effects of such 

 a strong ionospheric-electric field on unstable tropospheric situations 

 have been discussed already in part I of this paper. 



The heating of the absorbing gases and the dissociation of the 

 molecular oxygen lead to a momentary pressure rise in the absorbing 

 layer. Details about the amount of that pressure rise are not yet 

 known. 



The formation of certain chemical compounds, especially of O3, 

 H2O2, NH3, N2O5, NH4NO2, and NH4NO3, by ultraviolet irra- 

 diation of the high atmosphere, has been emphasized for many years 

 by P. Lenard and C. Ramsauer (33). The importance of such chem- 

 ical compounds for the condensation of water vapor has been dis- 

 cussed before Lenard by E. Pringal (34), E. Barkow (35), F. 

 Richarz (36), and later also by W. Bieber (37). The relationship 

 between high sun activity and the radius of the circumsolar shine, 

 which has been treated in detail by J. Maurer (38) and C. Dorno 

 (39), points likewise to atmospheric-turbidity phenomena which are 

 produced by an intensified ultraviolet irradiation. It may be assumed 

 also that the statistical accumulation of sun halos 2 days after intense 

 chromospheric eruptions, which has been stated by G. Archenhold 

 (22), is due to the additional production of condensation nuclei dur- 

 ing ultraviolet invasions. The possibility of a down-sucking of the 

 solar-produced condensation nuclei over cyclones in state of develop- 

 ment (Palmen, Refsdal) and certain thermodynamic consequences 

 have already been discussed on the occasion of examining the effects 

 of solar particles. The same is true for the regionally intensified 



