Māris kļaviņŠ, azamat azizov, JĀnis zaļoksnis environment, pollution, development: the case of uzbekistan

Partial pressure of ozone (mPa)
In the first stage of ozone molecule synthesis, an oxygen molecule 
is  excited  by  absorbing  the  UV  radiation  energy  (Figure 5.4).  The 
excited oxygen molecule splits into two oxygen atoms that are free 
Figure 5.2. 
Ozone 
molecule is composed 
of three interconnected 
oxygen atoms
Figure 5.3. 
Variability of 
the ozone concentration 
over the Antarctic 
and the absorption 
of UV radiation in the 
atmosphere depending 
on the UV radiation 
wavelength

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ENVIRONMENT, POLLUTION, DEVELOPMENT:  THE CASE OF UZBEKISTAN
to react with another oxygen molecule to form an ozone molecule. 
In this way, UV radiation is absorbed during the ozone molecule 
formation process, and the new ozone molecule also is capable 
of absorbing it. At the same time, UV radiation that has a shorter 
wavelength  (and  higher  energy)  splits  the  ozone  molecules.  As  a 
consequence, the concentration of ozone is decreasing in the upper 
layers of the atmo sphere. Thus, the Earth’s ozone layer is a region 
in the atmo sphere where the reactions of ozone molecule synthesis 
and destruction are in a state of a certain equilibrium (destruction 
reactions prevail in other parts of the atmo sphere), whereas higher 
concentrations of ozone are present in the stratosphere.
UV
O
2
O
2
O
2
+
+
O
O
O
3
O
3
Several factors affect the concentration of ozone: the move ment 
of air masses, natural, seasonal and other processes. The anthro-
po genic contamination of the atmo sphere has a crucial role in the 
ozone layer destruction processes. The atmo spheric contamination 
with halogenated hydrocarbons, produced in relatively large 
amounts, is considered to be particularly hazardous to the environ-
ment (Table).