286 
12 km), the warm pocket at this level coinciding with the pos- 
itive deviations, the cold with the negative. Since these warm 
and cold areas are unquestionably due to subsidence and lift- 
ing respectively, it seems reasonable to suspect that the vert- 
ical displacements also in some fashion affect the ozone con- 
centration. 
Reed, moreover, recently calculated the change in ozone 
content during vertical displacements on the basis of 
the fact, already emphasized by Regener, that in strong 
vertical mixing the ozone mixing ratio (grams of ozone 
per gram of air) is independent. of altitude. To begin 
with, the curve of ozone content versus altitude is 
transformed into a curve of ozone mixing ratio versus 
altitude. The curve is thereupon raised or lowered and 
finally reconverted back to an ozone content curve. 
In Fig. 15 it is assumed, at first, that the vertical dis- 
TROMSO 
INITIAL CURVE (TROMSO 0.340 CM) 
ee AFTER 
me--- oo SUBSIDENCE 
(COMPUTED) 
002 .,004 .006 .008 .0I0 O14 
CM O3 PER KM 
Fie. 15.—The effect of subsidence on the ozone distribution. 
-Ol2 
placement extends through the entire column of air 
[80]. More recently [81] the assumption was made that, 
im the closed region of high ozone amount to the west 
and southwest of an intense surface cyclone, the air 
subsides most markedly near the tropopause and that 
the sinking motion becomes unnoticeable above the 
tropopause between 16 and 18 km and below it at 7 to 
8 km. Thus, the vertical displacements take place only 
within the secondary advection layer. Figure 16 is 
HEIGHT (KM) 
SUBSIDENCE 
(COMPUTED) 
.002 .004 .006 .008 .010 .012 
CM O03 PER KM 
O14 ,O16 
Fic. 16.—The effect of subsidence on the ozone distribution. 
based on an Arosa curve for an ozone amount of 0.131 
em between altitudes of 5 and 20 km and an assumed 
THE UPPER ATMOSPHERE 
maximum downward displacement of 1.4 km and shows 
an ozone increase of 0.025 cm. A corresponding ex- 
ample for liftmg motion would yield a decrease of 0.017 
em. According to this new estimate, the contribution 
of the vertical motion in the interplay between ad- 
vection and vertical motion is less significant than in 
previous assumptions, for instance that of Nicolet [67]. 
According to Reed, vertical motions account for, at 
most, about 14 of the total range. In summer and in 
fall, when the ozone content of the lower stratosphere 
is considerably less and vertical motion much weaker, 
the vertical motion effect will be almost negligible. 
According to the upper-level weather maps, on which 
isobars generally have sinusoidal shape, advection and 
vertical motion always affect ozone changes in the same 
sense. In an influx of air from a ridge to a trough, the 
air comes predominantly from northern latitudes, and 
the consequent higher ozone amount is further in- 
creased by subsidence. In the example studied by Reed, 
the higher ozone content of 0.320 cm in an advectively 
transported air mass increases to 0.345 em owing to 
subsidence; by contrast, the ozone content of 0.260 cm 
is decreased to 0.243 cm in an air mass that is lifted in 
the northeast quadrant of a surface cyclone. 
Ozone Conditions in the Troposphere. Ozone condi- 
tions in the troposphere are evidently quite variable 
(Fig. 10), depending on the interplay of advection, 
which makes ozone suitable for air-mass analysis, with 
the turbulent ozone supply from the secondary tropo- 
pause layer (“flux d’ozone” according to Jaumotte, 
“Ozonstrom”’ according to V. H. Regener [86]). Whereas 
mixing produces an increase of ozone content at lower 
altitudes, it may happen in layers near ground level, in 
which ozone is consumed at a rapid rate by dust and 
oxidizable organic substances, that the ozone flow com- 
pletely disappears in the case of stagnant air [83]. As 
a result, a weak tertiary layer of ozone develops at an 
altitude of several kilometers which is of climatic signif- 
icance in high mountain regions. Starting from ozone 
near ground level, the significance of turbulence has 
been successfully demonstrated by E. Regener [82, 83] 
and his collaborators. The ozone stream treated theo- 
retically by Lettau [59] has only on the average a down- 
ward direction in the troposphere because of advective 
superposition of air masses and shows relatively pro- 
nounced irregularities in space and time. Glueckauf [85] 
explains the region .of diminished ground-level ozone 
ahead of a warm front on the basis of an interruption 
of the turbulent air exchange by the barrier layer of 
the front. 
Ozone and Radiation Flux. A direct physical in- 
fluence of ozone on meteorological processes through 
the medium of radiation flux has not been ascertained. 
As Lord Cherwell (Lindemann) suggested as early as 
1919, ozone is as important for radiation balance in the 
lower stratosphere as are water vapor and carbon di- 
oxide. However, any temperature rise due to increased 
ozone evidently takes place so slowly that it cannot 
be detected in meteorological circulation processes. 
However, in the case of a prolonged influence, the 
effect of ozone on incident and emitted radiation can 
