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where Q
e
is the concentration of
ʵ
-th radionuclide in the bottom sediments and H
/
is the rate of the output
-th radionuclide from the bottom sediments via
desorption. The exchange of radionuclides between the water layers by migration of
living elements is ignored as it has a small value in comparison with the
fl
flow of the
ʵ
ow H
e
D
.
fl
6.4.6 Simulation Results
6.4.6.1 The Assumptions
The SSMAE allows for the estimation of the pollution dynamics of the Arctic Basin
under various a priori suppositions about the intensities of the flows of pollutants
and under other anthropogenic impacts on the ecosystems of this region. Here,
some of the possible situations are considered. The thermal regime of the Arctic
Basin is given by a normal distribution with average temperatures and with dis-
persions on the aquatories as given by the SEDAAR (Strategic Environmental
Distributed Active Archive Resource). The scheme of transport of pollutants in the
atmosphere is adopted from Christensen (1997). The estimates of parameters for the
blocks of Table
6.7
are given by literature sources or personal recommendations.
The vertical distribution of pollutants in the initial moment t
0
is taken as
homogeneous. The average diameters of the solid particles are estimated to be in the
range from 0.12 to 1,000
m and the vertical velocity of sedimentation is 0.003 m/s.
The concentration of nutrients in the ice and snow equals 0. Also it is supposed that
the deep water temperature is de
ʼ
ned as
ʥ
(t,
φ
,
ʻ
)=0
°
C and the surface ice
1
¼ 0 and the
phytoplankton productivity in the ice layer is 2.5 % of the primary production in the
water column [(R
p,r
+R
pf
)/R
p,w
= 0.025].
Let the ratio between solid and dissolved phases of heavy metals at the moment
t=t
0
equal 1:2, i.e. e(t
0
,
temperature as f
1
(t,
φ
,
ʻ
)=
−
3
°
C for (
φ
,
ʻ
)
∈ Ω
. It is supposed that
e
φ
,
ʻ
,z)/
ˈ
(t
0
,
φ
,
ʻ
,z) = 0.5. The
fl
flows of heavy metals,
H
Z
;
H
F
;
H
D
and H
L
, are described by linear models, H
1
¼ 0
01 e
w
, H
e
a
= 0. The
boundaries of the Norwegian and Bering Seas are approximated by lines with
φ
N
=62
:
ned
by Wielgolaski (1997), Wania et al. (1998), Valette-Silver (1999), Preller and
Cheng (1999), Bard (1999) and Rudels et al. (1991). The initial data are de
°
Nand
φ
B
=51
°
N, respectively. Values for the other parameters are de
ned in
Tables
6.5
and
6.8
.
6.4.6.2 The Dynamics of Arctic Basin Radio Nuclear Pollution
The intensity of external
fl
flows through the boundaries of the Arctic Basin and the
flows due to dead organisms H
e
D
, sediment H
e
and living organisms H
a
internal
are
described by linear models in accordance with Krapivin and Phillips (2001b). Some
results of the simulation experiment are given in Figs.
6.8
,
6.9
and
6.10
. Figure
6.8
fl
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