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or empirical character. The coef
cients of water surface emission on the horizontal,
h
k
V
k
j
, and vertical,
j
, polarizations are calculated with the Frenel formulae:
2
1
=
2
h ðe
k
sin
2
k
¼ 1
e
k
cos
hÞ
h
j
;
ð
2
:
8
Þ
h þðe
k
sin
2
1
=
2
e
k
cos
hÞ
2
1
=
2
h ðe
k
sin
2
cos
hÞ
V
k
¼ 1
j
;
ð
2
:
9
Þ
1
=
2
h þðe
k
sin
2
hÞ
cos
where
ʵ
ʻ
is the water dielectric permittivity at the wavelength
ʻ
being the function
of
salinity,
temperature
and
other
parameters
of
upper
ocean
layer;
1
a
1
Þ;
e
k
¼
e
0
k
i
e
0
k
ðe
0
k
¼ 5
5
þ
a
1
; e
0
k
¼
k
S
k
:
2
0081t
2
a
1
¼½
e
S
5
:
5
=
½1
þðk
S
=kÞ
; e
S
¼ 0
:
0
:
40885t
þ
88
:
2
;
t ¼ T
SO
273
;
000136t
2
k
S
¼ 1
:
466exp
0
if
:
0634t
g þ
0
:
0
:
0272t
þ
1
:
8735
:
ʵ
ʻ
with consideration of water salinity variations S can
take into account by the approximate formula:
A correction to the value
ʵ
S
(S)=
ʵ
S
(0)
−
17.2S. From
expressions (
2.8
) and (
2.9
) under vertical observation (
ʸ°
=0
°
) we receive:
h
v
o
j
k
¼
j
k
¼
j
k
¼ P
j
, where
1
=
2
cos
ðd
k
=
1
=
2
cos
ðd
k
=
P
j
¼ 4
je
k
j
2
Þ =
½
je
k
jþ
2
je
k
j
2
Þþ
1
;
00
k
=e
0
k
angle
ʴ
ʻ
is determined by the expression tg
d
k
¼
e
.
¼ 1
and proposed a constructive algorithm to calculate the surface temperature T
S
with
the measurements of T
j,h
and T
j,V
under the observation angle
2
h
k
h
v
k
Andreev et al. (1984) analyzed Shepovalov
'
s invariant
j
=
2
j
k
j
Ò
j,h
)
2
/
ʸ
=45
°
:
Ò
S
=(
(2T
j,h
−
±
3 K. It is valid for the cal-
culation both T
SO
and land thermodynamic temperature. The T
j
practically depends
on T
SO
linearly with the slope from 0.35 to 0.5. An increase of salinity from 0 to
40
‰
is provided with the increase of T
j
under
ʻ
< 3 cm by values no exceeding 3 K
and with essential decrease of T
j
under
T
j,v
). This algorithm has the precision less
[8, 10] cm by the values up to 40 K. The
dependence slope of this decreasing as the function of S is function of T
SO
.
Knowledge of the radiation dependencies of water surface properties on the total
spectrum of water surface parameters is the essential basis of a radiometric control
system of the ocean surface.
In the case of water object with great conductivity (sea water) for the decimetre
range the following correlation is valid:
ʻ ∈
)
1/2
, where f is the radiowave
ʺ ≅
0.5(f/
˃
frequency,
is the water conductivity. This expression allows to estimate the water
conductivity if the water thermal emission is measured. If the substance dissolved in
the water and its conductivity are known the dissolved substance concentration is
˃
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