Geoscience Reference
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precipitation, it is necessary to consider all dynamic microphysical interactive
processes. These processes are determined by a combination of physico-chemical
parameters of the atmosphere itself and pollutant components, which are charac-
terized by strongly variable characteristics such as weight, concentration, size,
shape, phase state, and electric charge. For instance, the classi
cation of atmo-
spheric aerosol pollution adopted by the US National Oceanic and Atmospheric
Administration (NOAA) includes three basic classes and eight sub-classes. This
classi
cient to be used in models which do not take into account the
size of aerosol particles and do not include the ion-level processes.
The existing classi
cation is suf
cation of particles by the size covers the particles
'
diameters
from 0.0001
m
are considered as smoke components, while liquid particles are elements of fog.
Particles exceeding 1
ʼ
m to 1 cm. Within this range, solid particles with D = 0.0001
1
ʼ
-
m in diameter are interpreted as dust or spray. Depending on
the size, the role of particles in dynamic processes of atmospheric pollution
changes, too. Particles with diameter less than 1
ʼ
ʼ
m form smog, tens of
ʼ
m
—
clouds
and fog, hundreds of
ʼ
m
—
haze and drizzle, thousands of
ʼ
m
—
rain. This classi-
s structure, if the nature of processes of
atmospheric pollution is known. In a more complicated situation, when the size
spectrum of aerosol particles is suf
fication simpli
es the choice of the model
'
ciently broad, the division of pollutants by their
physical and chemical characteristics enables one to synthesize the complicated
model as a totality of hierarchically submitted partial models and to simplify
thereby the procedure of calculation of dynamic characteristics of the polluted
atmosphere.
The physical characteristics of atmospheric pollution include also the rate of
gravitational deposition, residence in the atmosphere, and phase state. Some of the
atmospheric gas components such as N
2
,O
2
, He, Ne, Ar, Kr, Xe, and H
2
have a
very long lifetime. The lifetime of CO
2
,O
3
,N
2
O, and CH
4
is from several years to
decades. Such gases as H
2
O, NO
2
, NO, NH
3
,SO
2
,H
2
S, CO, HCl, and I
2
live in the
atmosphere only several days or weeks. Depending only on this characteristic to
describe the dynamics of various gases in the atmosphere, one can choose an
adequate model with minimum requirements for database (Kondratyev et al. 2006a;
Bornstein 1999).
For the choice of the type of the polluted atmosphere dynamics model, the size
of an aerosol particle is of great importance. The mentioned intervals only partly
cover a possible classi
cation of aerosols. Additional information is needed about
the source of pollutant which further speci
es the parametric space of the model.
The knowledge of the cause of pollution simpli
es the choice of the model type. Of
course,
cation of aerosols and gases can be more
detailed. For instance, there are tens of the types of smoke. The size of smoke
particles can be 1
the classi
cation and typi
m for tobacco smoke, etc.
Here, in the model, it is necessary to consider micro-processes connected with the
motion of these particles. For instance, the run of a particle of carbonaceous smoke
during t seconds averages 0.00068 t/D cm. Filling the base of knowledge of the
monitoring system with such dependences is one of the
-
0.01
ʼ
m for resin smoke, 0.15
-
0.01
ʼ
first-priority problems of
ecoinformatics.
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