Geoscience Reference
In-Depth Information
Table 1.20 Estimates of the
fluxes of particles with the
radius <29
ʼ
m either emitted
to the atmosphere or formed
in-situ
Type of particles
Amount of particles
(10
6
t/year)
Particles of natural origin
(weathering, erosion, etc.)
100
-
500
Particles from forest
res and
forestry wastes burning
3
150
-
Sea salt
300
Volcanic dust
25
-
150
Particles from gas emissions
Natural processes
Sulphates from H
2
S
130
200
-
Ammonium salts from HN
3
80
-
270
Nitrates from NO
x
60
430
-
Hydrocarbons from vegetative
compounds
75
200
-
Anthropogenic processes
Sulphates from SO
2
130
200
-
Nitrates from NO
x
35
Hydrocarbons 15
-
90
Amounts of particles emitted to the atmosphere
Natural
30
-
773
2,200
-
Anthropogenic
185
415
-
Total flux of particles into the
atmosphere
958
-
2,615
The mechanism of the effect of particles on atmospheric temperature is explained
by that solar radiation coming to the Earth, mainly within the range 0.4
4
ʼ
m, is
-
partially re
ected and absorbed by them. The global albedo of the surface-atmo-
sphere system varies, too. Besides, the particles affect the processes of moisture
condensation in the atmosphere, since clouds, rain, and snow form with their
participation. Take the heat balance equation of the system
fl
“
surface-atmosphere
”
:
ð
1
aÞ
E
o
þ
E
a
r
T
s
¼
0
;
ð
1
:
11
Þ
where T
s
is the average ef
cient temperature of the system
'
Ts emission, close to the
the surface 400 mb, E
o
¼
temperature of
the average energy level near
487 cal/cm
2
0
:
=
min is the mean-hemispherical
intensity of the incoming solar
10
−
11
cal/cm
2
/min is the Stefan-Boltzmann
constant, E
a
is total intensity of the anthropogenic sources of energy per unit
surface.
Let albedo
radiation;
ʱ
is albedo;
˃
= 8.14
×
ʔʱ
is a small part of albedo determined by the impact of anthropogenic aerosols. From
the Eq. (
1.11
) we obtain an expression for temperature:
ʱ
=
ʱ
o
− ʔʱ
, where
ʱ
o
= 0.35 is the albedo in present conditions,
Search WWH ::
Custom Search