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is certainly effective at determining the chemical composition of the atmosphere,
wind speed, temperature, cloud parameters, and dust formations (Klyuev 2000).
The diagnostics of water content in the clouds, compound of atmosphere gases and
aerosols by its thermal radiation in the microwave range is based on the spectral
measurements (Strelkov and Soldatova 1989).
Many authors use the millimeter wavelength band to diagnose atmospheric
gases. Strelkov (1995, 1996) implemented the estimates of atmospheric track
optical depths between two satellites on admixture gases CO and N
2
O resonance
absorption frequency in millimetre and submillimetre bands with taking into
account the data on their atmospheric concentrations. It was shown that optical
depths are completely de
ned by admixture gases from the sighting dis-
tances
15 km and can be measured, which indicates the use of the active remote
sensing method of the atmosphere for CO and N
2
O contents de
≈
nition. Intrusion of
these gases to the atmosphere is caused by anthropogenic factors to a considerable
extent. But it is problem for many biogeochemical processes such as ozone cycle.
That is why possibility of the measurement of these gases concentration with
satellite systems is signi
cant achievement.
Strelkov (1996) developed new method for measuring the concentration of water
vapor in the mesopause by active sensing at resonance wavelengths of the rotational
spectrum. He showed that for two-frequency sensing, simultaneous measurement of
the height profiles of the concentration of water vapor and of the temperature within
the mesopause is possible. This method is based on the fact that within the
mesopause water vapor completely determines the optical depth of the sensing path
in the centres of its spectral lines with wavelengths
ʻ ≥
0.5 mm. Moreover the
absorption coef
cient
in the centre of the line with resonance frequency fi
i
is
described by the expression
c
D
2
N
3hcG
ð
T
Þ
8
p
hcf
i1
kT
hcf
i2
kT
a
i
¼
f
i
ljj
exp
exp
T
Þ
;
f
i
ð
P
;
where N is the concentration of water vapor molecules, h is the Planck
'
s constant
10
−
34
J), c is the speed of light (=3
10
8
ms
−
1
), k is the Boltzmann
(=6.55
×
×
'
s
10
−
23
JK
−
1
), G(T) is the rotational statistical sum, fi2
i1
and f
i2
are the
lower and upper energy levels of transition with frequency fi
i
= fi
i2
-
constant (=1.3
×
f
i1
,
μ
i
is the dipole
moment matrix element for transition with frequency Δfi
i
,
f
i
is the half-width of the
line which depends on the pressure P and the air temperature T, z is the height.
Scienti
ʔ
c and technical achievements in the satellite monitoring of atmosphere
gases are important in connection with the greenhouse effect and ozone problems
(Kondratyev and Varotsos 2000; Zuev 2000; Krapivin and Nitu 2011). The active
and passive sensing of some atmospheric gases from satellite board with millimetre
and submillimetre wavelengths allow to measure the content of O
2
,O
3
,N
2
O, H
2
O,
CO, BrO, ClO and HCl. For example, the possibility of active sensing of the added
gas is equivalent to the possibility of reliable measurement of the inter satellites
trace optical depth,
˄
, stipulated by the gas:
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