Geoscience Reference
In-Depth Information
(
)
(
"
#
)
2
2
Q
2
p
V
r
k
r
h
exp
1
2
k
r
k
1
2
h
Z
r
h
1
2
h
þ
Z
r
h
C
u; k;
h
ð
Þ
¼
exp
þ
exp
ð
1
:
2
Þ
where
ˆ
is the wind direction,
ʻ
is the abscissa, h is the ordinate,
˃
ˆ
and
˃
p
are the
horizontal and vertical dispersions (scattering).
In the second zone the air-pollution cloud forms under instability conditions and
therefore the calculation of the air-pollutant concentrations requires a broadened
information base.
Assuming that:
u
0
—
the leeward distance from the intersection of the cloud with
the upper part of the boundary layer,
r
0
—
average value of scattering at
the
boundary between the stable and unstable zones, p
0
¼ L
½
ðÞ
Z
=r
h
;
L
ðÞ—
the
height of the boundary layer in the leeward direction
ˆ
, then:
(
)
2
2
2
Q
1
ð
p
0
Þ
1
2
k
r
0
3
=
2
Z
u
0
C
ð
u; k;
h
Þ
¼
Þ
V
exp
r
0
r
h
V
ð
; u; u
0
ðÞ
2
(
"
#
"
#
)
2
2
p
0
@u
0
d
exp
h
Z
ð
Þ
ð
h +Z
Þ
@
0
þ
exp
u
ð
1
:
3
Þ
2
2
2
r
h
V
ð
; u; u
0
Þ
2
r
h
V
ð
; u; u
0
Þ
c enough due to the conditions of cloud formation.
This cloud is completely inside the atmospheric boundary layer (ABL), and the
concentration of pollutants within it can be calculated with the formula:
The third zone is quite speci
"
#
2
Q
1
2
k
r
h
ð
u; k;
Þ
¼
p
V
r
k
r
h
exp
C
h
2
(
"
#
+ exp
"
#
)
2
2
h
Z
r
h
h
þ
Z
r
h
1
2
1
2
exp
ð
1
:
4
Þ
for
˃
h
< 0.47L(
ˆ
), and
"
#
2
Q
1
2
k
r
k
C
ð
u; k;
h
Þ
¼
exp
ð
1
:
5
Þ
p
V
r
k
L
ðÞ
for
) the concentration C is
calculated with the interpolation formula between the points
˃
h
> 0.8L(
ˆ
). Within the interval 0.47
≤
L(
ˆ
)
≤
0.8L(
ˆ
˃
h
= 0.47L(
ˆ
) and
˃
h
= 0.8L(
).
The Gauss-type model describes well the
ˆ
fields of air-pollutants over territories
at scales up to 100 km. For large territories, other types of models are used. For
example, Eulerian and Lagrangian models are used when Gaussian model appears
high errors. The item ESA employs these models depending on the territory area
and taking into account the availability of monitoring data.
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