Botkin Environmental Science Earth as Living Planet 8th txtbk

Altitude (km)
(b)
80
60
40
20
Mesosphere
Stratosphere
Troposphere
0
0.4 4 40 400
Ozone concentration
at 60south latitude (ppb)
(a)
Incoming solar radiation
~99% of the
ultraviolet solar
radiation is
screened out
in ozone layer
Ozone (O 3 )
layer
Human activity,
weather, and air
pollution
Stratosphere
Troposphere
Surface
of Earth
(not to
scale)
40 km
15 km
10 km
FIGURE 21.14 (a) Structure of the atmosphere and ozone
concentration. (b) Reduction of the potentially most biologically
damaging ultraviolet radiation by ozone in the stratosphere.
(Source: Ozone concentrations modified from R.T. Watson,
“Atmospheric Ozone,” in J.G. Titus, ed., Effects of Change in
Stratospheric Ozone and Global Climate, vol. 1, Overview, p. 70
(U.S. Environmental Protection Agency).
21.3 High-Altitude (Stratospheric) Ozone Depletion 481
21.3 High-Altitude
(Stratospheric) Ozone
Depletion
-
2
Ozone (O 3 )
Stratosphere ozone (ozone layer):
Contains 90% of atmospheric ozone;
it is the primary UV radiation screen.
Troposphere ozone:
Contains 10% of atmospheric ozone;
it is smog ozone, toxic to humans,
other animals, and vegetation.
Ultraviolet Radiation
and Ozone
-
ozone shield -
-
-
2
2
-