1130 
during conditions of sharply increased conductivity or 
low electric potential. This phenomenon is strikingly 
parallel to the low O3 values in air that has been en- 
riched by radioactive emanations, that is, the highly 
conductive air at radioactive spas [9, 19]. The objection 
could be raised here that O; is produced during the 
decay of radium. This is, indeed, the case for the 
principal members of the decay series, or rather, O3 is 
produced by their electrons which are either not de- 
celerated or decelerated only slightly. However, the 
quantity of O; thus produced is extraordinarily small, 
although numerous excited and ionized atoms and mole- 
cules will simultaneously be formed by secondary radia- 
tion. Therefore the principal effect of the emanations 
from the ground is probably not an increase of the O3 
content but an increase of the ionization of the air. 
The strongly decreased values observed during foehn 
can thus be explained by the fact that air subsiding from 
greater altitudes is already deficient in O3 as well as 
by the fact that the O; is almost completely eliminated 
by reduction processes in strata near the ground be- 
cause, as a result of the high conductivity, no electron 
accelerations sufficiently great for local O3 formation 
can occur from grounded point dischargers in the air 
near the surface, or between clouds. Equally low values 
of O3; are observed at the inception of condensation 
phenomena during the formation of fog and protracted 
precipitation with mist, and likewise in the presence of 
tobacco smoke and cooking vapors indoors. The reaction 
mechanism for the elimination of O3 in such cases is 
still unexplained. It must be assumed that O3 during 
fog formation reacts with reducing substances such as 
ammoniacal.compounds. This appears to be the reason 
for the low values and small fluctuations of O3 in for- 
ests, where particularly intensive exhalations of re- 
ducing anaerobic decomposition products occur. 
During fair weather, the mean values increase. The 
air behind a cold front, which has few middle- and large- 
sized nuclei because of their removal by rain, is fre- 
quently still poor in O03. The O; values increase only 
when the number of small nuclei decreases and that of 
the large nuclei increases, or, in other words, concur- 
rently with the intermittent increase of the potential 
occurring frequently durmg such weather. Similar phe- 
nomena may be observed when rather low clouds or high 
fogs move by and when brief precipitation sets in 
(Lenard effect). The abrupt increase of the values 
during subsidence phenomena from lower altitudes 
(height of the lower clouds) is also very informative. 
This increase, in the author’s opinion, is caused by O3 
which originated during electrical discharge processes 
in nonhomogeneous fields between clouds. However, in 
addition to this, the formation of O; at grounded 
point dischargers might be of considerable local impor- 
tance. In fact, it has been shown by investigations on 
lightning rods [13] that, even in fair weather, values are 
found around these devices which are three times larger 
than those recorded farther away. Thus, the quantities 
of O; that emanate from such discharger tips into the 
surrounding air are considerable as compared with the 
average total O3. Ozone from grounded dischargers was 
BIOLOGICAL AND CHEMICAL METEOROLOGY » 
recently found by the present author in investigations 
over a limited measuring field in Wyk on the island of 
Fohr. In these investigations it was particularly striking 
to note that considerable absolute differences occurred 
over distances of a few meters, but that the trend in the 
fluctuations was everywhere the same without excep- 
tion. At constant wind the values were consistently 
higher at one measuring station than at the other, a 
behavior pattern which was sometimes reversed when 
the wind changed. From the foregoing observations one 
gets the impression that sometimes the one measuring 
station and sometimes the other was subject to the 
effect of O; from a more intense source in the field. 
A rough calculation by Reiter,” based on findings by 
Schottky, shows that, with a potential of 130 v m on 
a hemispherical conductor tip of 0.5 em? surface area 
one meter above the ground, the potential may reach 
1,000,000 v m™ over partial conductor points (micro- 
scopically small elevations). However, a potential of 
only 500,000 v m™ is sufficient to produce electrons 
having the acceleration of 8 ev required for O3 forma- 
tion, assuming an average of 10° electron impacts before 
adhesion to gas molecules. The formation of O3 at 
grounded conductor tips such as on lightning rods there- 
fore appears possible even in a normal electrostatic field. 
To what extent this occurs at less elevated conductor 
tips has not been investigated sufficiently to permit any 
definite statements. However, chemical measurements 
indicate that O; is formed even with lower points during | 
rather brief intensive fluctuations of the electric field. 
It is not possible with our present knowledge to appraise 
the significance of such O3 formation near the ground 
as compared with the O; production in nonhomogeneous 
electrostatic fields between clouds, augmented perhaps 
by O3 from the stratosphere, although the subsidence 
of O3 from great heights has never been satisfactorily 
demonstrated. For the solution of this problem exten- 
sive investigations of O3 are needed, involving not only 
measurements from field stations and aircraft, but also 
analyses with respect to the companion reactions and 
the reaction products of O3. Furthermore, the rapid 
fluctuations (within seconds) of the electrostatic field, 
and the change of the number of nuclei must be meas- 
ured simultaneously, as was done in the extensive work 
by Landsberg in collaboration with Amelung [1]. 
Total Oxidation of the Air. Fluctuations of the oxi- 
dation values are preponderantly parallel to those of 
O:, but opposing trends may also occur. In the Taunus 
region [13] the mean was 15 ug active oxygen per cubic 
meter, in Norderney [14] it was about 24 pg m-*. Pre- 
vious oxidation values [11, 12] were always lower as 
compared to the values derived from the deficiency in 
active oxygen, or from the reduction values. Where 
reducing substances are lacking, as in desert regions or 
in the Arctic, the total oxidation values are probably 
large and effective. The total oxidation values are pro- 
duced by the oxidizing effects of O3, NO:, ClO2, Clo, 
Br, Iz, and oxides of the latter two halogens. Despite 
thousands of analyses by means of titanium sulfate, 
2. Personal communication. 
