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with unpredicted consequences. These estimates are important for the
nal conclusion
about the level of the integral greenhouse effect. However, the solution of this problem
is connected with many factors, neglecting of which leads to serious errors. For
instance, the CH
4
fl
le
of the temperature in the marsh body. In a simplest case, if we denote as T
W
(z, t) the
temperature at a time moment t at a depth z and write the equation of heat conductivity
flux on the border atmosphere-marsh depends on the vertical pro
2
T
W
ð
z
;
t
Þ
@
@
T
W
ð
z
;
t
Þ
@
¼ a
2
@
ð
1
:
6
Þ
t
z
2
where a
2
¼ Kc
1
1
,
c heat
capacity,
q
is the medium density, then an estimation of the flux F
CH
4
as a time
function becomes dependent of the multitude of the poorly assessed characteristics
of the environment.
Let
q
К
is the coef
cient of heat conductivity, c is speci
the marsh surface temperature vary cyclically with frequency
ˉ
and
·
ˉ
amplitude A, decreasing with depth: T
W
(0, t)=A(z)
cos(
t), where
r
2a
z
A
ð
z
Þ
¼A
ð
0
Þ
exp
ð
1
:
7
Þ
The solution to Eq. (
1.7
) enables us to trace the temperature variations T
W
(z, t) and
suggests the conclusion that in this case these variations weakly depend on T
W
(0, t).
Even if T
W
(0, t) increases by 2
C, then according to (
1.7
), the amplitude of temper-
ature changes with depth will rapidly decrease to 0.97, 0.33, and 0.01
°
°
C at depths
40 cm, 2 m, and 3 m, respectively. Hence, with a 2
°
C increase in the average global
ux F
CH
4
will increase by no more than 1.4 %.
Comparing the global signi
atmospheric temperature,
fl
cance of the CO
2
and CH
4
cycles in the system
atmosphere-marshes, note that the CO
2
cycle promotes a climatic stabilization,
whereas the CH
4
cycle intensi
es the climate changes. With a climate warming the
marshes assimilate part of CO
2
from the atmosphere and reduce thereby the
greenhouse effect. On the contrary, when the climate warms due to increasing F
CH
4
,
the greenhouse effect intensi
es.
The western Siberian region of Russia is characterized by numerous intensive
natural and anthropogenic sources of methane formation. These are marshes, tun-
dra, permafrost, oil and gas deposits. In this region the
ux F
CH
4
varies widely both
during a year and shorter time periods. From measurements carried out by
Jagovkina et al. (2000) at the coastline of Yamal in June 1996, the CH
4
concen-
tration in the atmosphere at a height of 2 m varied from 1.83 ppmv in June, 18 to
1.98 ppmv in June, 23, with an average daily value of 0.032 ppmv.
The peatbogs of Siberia are quite special in the global cycle of methane. They
play a unique role in the biogeochemical cycles of methane and carbon dioxide. On
the one hand, they are a non-anthropogenic source of CH
4
and CO
2
, but on the
other hand, they are intensive assimilators of carbon from the atmosphere and
extract it from the natural cycle for a long time. The marshes of West Siberia, for
fl
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