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spatial distribution. One of the widespread correlation functions is the dependence of
variations of average temperature
ʔ
T of the atmosphere on the CO
2
content in it:
2
:
5½1
exp
f
0
:
82
ðn
1
Þg;
n
1
;
D
T ¼
ð
1
:
8
Þ
2
5
:
n
þ
12
:
n
7
:
;
n
\
25
55
3
1
where
is the ratio between the present content of CO
2
in the atmosphere C
a
(t) and
its pre-industrial level C
a
(1850).
As seen from (
1.8
), T is an increasing function of the amount of atmospheric
CO
2
. A 20 % increase of CO
2
in the atmosphere raises the temperature by 0.3
ʾ
°
C. A
doubling of atmospheric CO
2
causes an increase of T by 1.3
C. A detailed analysis
of the function (
1.8
) and a comparison of the observed combined variations of
ʔ
°
show that the use of the model (
1.8
) makes it possible to simplify the
climate unit of the global model. In particular, if
ðD
T and
ʾ
T
Þ
2½CO
2
is calculated by (
1.8
)
with a doubled concentration of atmospheric CO
2
, then to assess the present trends
in changes of T
g
the following formula can be used:
D
T ¼
ðD
T
Þ
2½CO
2
ln
n=
ln2
;
ð
1
:
9
Þ
where, from the assumed estimates, the pre-industrial value of C
a
(1850) = 270 ppm.
The formula (
1.9
) satisfactorily approximates the known data with an error of about
50 %. It follows from (
1.9
) with C
a
(1980) = 338 ppm that
ʔ
T = 1.3
°
K, whereas a
real warming is estimated by many authors at 0.6
K.
Of course, the results of the recent discussions on the greenhouse effect in
connection with the growth of the CO
2
partial pressure in the terrestrial atmosphere
should be re
°
ected in GIMS. The formula (
1.9
) takes into account the impact of
CO
2
. According to Mintzer (1987), there is a possibility to broaden a consideration
of the temperature effect of other greenhouse gases:
fl
D
T
R
¼
D
T
CO
2
þ D
T
N
2
O
þ D
T
CH
4
þ D
T
O
3
þ D
T
CFC11
þ D
T
CFC12
;
where
D
T
CO
2
¼
0
:
677
þ
3
:
019
ln C
a
ðÞ=
C
a
t
ðÞ
½
;
n
o
1
=
2
1
=
2
D
T
N
2
O
¼ 0
:
057 N
2
O
ðÞ
½
N
2
Ot
ðÞ
½
;
n
o
1
=
2
1
=
2
D
T
CH
4
¼ 0
:
19 CH
4
ðÞ
½
CH
4
t
ðÞ
½
; D
T
O
3
¼ 0
:
7 O
3
ðÞ
O
3
t
ðÞ
½
=
15
;
D
T
CFC11
¼ 0
:
14 CFC11
ðÞ
CFC11 t
ðÞ
½
;
D
T
CFC12
¼ 0
:
16 CFC12
ðÞ
CFC12 t
ðÞ
½
:
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