Geoscience Reference
In-Depth Information
110
0.0001
100
THERMOSPHERE
0.001
90
0.01
MESOPAUSE
NOCTILUCENT CLOUDS
80
70
0.1
MESOSPHERE
60
50
1
STRATOPAUSE
40
OZONE
REGION
10
30
STRATOSPHERE
POLAR
STRATOSPHERIC
CLOUDS
OZONE MAXIMUM
20
100
CUMULONIMBUS
CIRRUS
Mt Everest
TROPOPAUSE
10
TROPOSPHERE
1000
0
-100
-80
-60
-40
-20
0
20
(°C)
-120
-80
-40
0
40
80 (°F)
Figure 2.15
The generalized vertical distribution of temperature and pressure up to about 110km. Note
particularly the tropopause and the zone of maximum ozone concentration with the warm layer above. The
typical altitudes of polar stratospheric and noctilucent clouds are indicated.
Source: After NASA (n.d.). Courtesy NASA.
The equator-pole (meridional) temperature
gradients in the troposphere in summer and winter
are roughly parallel, as are the tropopauses (see
Figure 2.16
), and the strong lower mid-latitude
temperature gradient in the troposphere is
reflected in the tropopause breaks (see also
Figure
7.8
). In these zones, important interchange may
occur between the troposphere and stratosphere,
and vice versa. Traces of water vapor can penetrate
into the stratosphere by this means, while dry,
ozone-rich stratospheric air may be brought down
into the mid-latitude troposphere. Thus above-
average concentrations of ozone are observed in
the rear of mid-latitude low pressure systems
where the tropopause elevation tends to be low.
Both facts are probably the result of stratospheric
subsidence, which warms the lower stratosphere
and causes downward transfer of the ozone.
