Geoscience Reference
In-Depth Information
precipitation, river
fl
flows and in
fl
flows of water from the Atlantic and Paci
c Oceans.
Its change with time in
ʞ
ijk
is described by the equation of heat balance:
f
C
r
ijk
@
T
ijk
@
t
¼
X
s
;
l
;
m
W
ijk
slm
þ
f
ijk
W
ijk
ð
6
:
9
Þ
slm
is the seawater density (g cm
−
3
); C is the water thermal capacity,
(cal g
−
1
grad
−
1
);
where
ʶ
ʞ
ijk
; W
ijk
˃
ijk
is the volume of
slm
is the heat in
fl
ow to
ʞ
ijk
from
ʞ
slm
;
f
ijk
slm
is the heat exchange between
ʞ
slm
and
ʞ
ijk
caused by turbulent mixing; and W
ijk
is the total heat out
ʞ
ijk
to the bordering boxes. Heat exchange with the
atmosphere is calculated in accordance with empirical Eq. (
6.1
).
It is considered that the dissipation of moving kinetic energy, geothermic
fl
ow from
ow
on the ocean bed, heat effects of chemical processes in the ocean ecosystem, and
freezing and melting of the ice are not global determinants of the water temperature
fl
fields. The SSMAE does not consider these effects.
The dynamics of the water salinity S(t,
φ
,
ʻ
,z) during the time interval t are described
by the balance equation as blockMWSD. The ice salinity is de
ned by a two-step scale:
s
1
—
old, s
2
—
new. It
is supposed that S
ð
t
; u; k;
z
Þ
¼s
0
for
z
100m, s
2
¼
[
k
s
S
ð
t
; u; k;
f
Þ
for r
þ
f
H
max
and s
1
¼ k
r
s
2
H
max
=ð
r
þ
f
Þ
for r
þ
f
H
max
where
[
\
coef
cients k
s
and k
r
are determined empirically and H
max
is the maximal thickness of
new ice. In accordance with the estimations by Krapivin (1995), the simulation
experiments are realized for H
max
= 50 cm, k
s
= k
r
= 1. The river
fields and
synoptic situations are described by scenarios given in the MRF and SS blocks and
formed by the user of the SSMAE.
The snow-layer thickness g(t,
fl
flows, ice
)
may be described via
st
atistical data with
given dispersion characteristics: g ¼ g
þ
g
0
where the value g is de
φ
,
ʻ
ned as the
mean characteristic for the chosen time interval and the function g
0
t
ð
; u; k
Þ
gives
the variation of g for the given time interval.
An alternative description is the parameterization of the snow-layer dynamics
process in the framework of the atmospheric process simulation algorithm (block
APTM) relating the thickness of the growth and melting of the snow-layer to the
temperature and precipitation:
gt
þ D
ð
t
; u; k
Þ
¼ gt
ð
; u; k
Þ
S
F
S
M
;
where S
F
is the part of the snow precipitated at temperatures close to freezing
(265 K
275 K) and S
M
is the snow ablation (i.e. evaporation + melting).
Block SS gives to the user the possibility to select between these algorithms.
When statistical data on the snow-layer thickness exists, the function g(t,
≤
T
0
≤
φ
,
ʻ
)is
reconstructed for (
by means of the approximation algorithm at the time
and polynomial interpolation in the space (Krapivin 2000c, d; Nitu et al. 2000b).
φ
,
ʻ
)
∈ Ω
Search WWH ::
Custom Search