TRANSPARENCY OF AND VISIBILITY IN THE EARTH'S ATMOSPHERE

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP79-00202A000100040001-2
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 71
• Document Creation Date: November 9, 2016
• Document Release Date: July 27, 1998
• Sequence Number: 1
• Publication Date: October 26, 1953
• Content Type: REPORT

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25X1A5a1
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TABLE OF CONTENTS
Page
I. Introduction ................................................ 1
II. Report No. 1 - Soviet Investigation of the Trans aren
of the Earth's Atmosphere 2
25X1A5a1
Part A - K.S. Shifrin. - Scattering of Light from Large
Water Droplets and the Polarization of the
Light in Rainbows . ........................... 6
Part B - E.V. Pyaskova-Fesenkova. - Some Data on the
Optical Properties of Atmosphere under Mountain
Conditions ....................................
Part C - S.F. Rodionov. - Transparency of the Atmosphere
in the Ultraviolet Region of the Spectruri. ????
III. Report No. 2 - Soviet Investigations of the Transparency of
the Earth's Atmosphere ???
39
47
25X1A5a1
54
IV. Bibliography - Transparency and Visibility of the Atmosphere 60
I. Akademiya Nauk SSSR (Academy of Sciences of the U.S.S.R.) 60
II. Leningradskiy Gosudartsvenny Universitet (Leningrad
State University) ...................................... 62
III. Institute Publications ................................. 63
IV. Glavnoye Upravleniye Gidrometeorologicheskoy Sluzhby
pri Sovete 11-:inistrov SSSR (Main Administration of the
Hydrometeorological Service under the Council of 21in-
isters of the U.S.S.R.) ................................
V. Periodicals Not Lttached to a Particular Institution ???
Vt. Books and Monographs ...................................
65
6$
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1. INTRODUCTION
The transparency and visibility of the atmosphere at any particular
location have considerable effect on the accuracy of position determina-
tion, the quality of aerial photography and consequently, on the accuracy
of maps compiled from that photography.
Soviet scientists apparently have consider2sx# g4oblem significant
enough to warrant considerable investigation.
collected and analyzed
Soviet scientific data dealing with this problem. Parts II and III of this
report contain his analysis of the quality and significance of Soviet work
in this field. Part IV is a bibliographic reference guide to additional
data found by the staff of this project in the course of its work on Soviet
geodesy, photogrammetry and cartography. No attempt has been made to collect
all available Soviet data on these subjects.
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II. REPORT NO. 1
on
SOVIET INVESTIGATIONS OF THE TRANSPARENCY
OF THE EARTH'S ATMOSPHERE
25X1A5a1
I have gone through all official publications of the Soviet Academy
of Sciences available to me, including the Doklady, the Izvestiya (Seriya
Geografich. i Geofiz; SerVa Fizicheskaya) and the Astronomicheskiy Zhurnal,
for recent years. There have been several important articles on the trans-
mission of light through the atmosphere, and abstracts of the three most
significant ones are enclosed.
These investigations are not generally known outside the Soviet Union.
At the present time they probably hE.ve no direct practical application.
But it seems certain that their elucidation of the action of aersols in air
will become increasingly valuable as these results are made use of in prac-
tical experiments.
Broadly speaking, Soviet research falls into three categories in this
field:
1. The theoretical determination of the scattering phase function for
large water droplets. The work by Shifrin, with its detailed tables, is
by far the best that I hsve seen (Part A). In practice most aerosols are
in the nature of either large water droplets or ice crystals. Shifrin's
theory does not apply to the latter. But it should become immediately ~.p-
plicable to problems of scattering in fog, and various kinds of clouds.
Fog particles range between 1,k and 120/L in diameter, cloud particles
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average between 8# for stratus to 2014 for nimbostratus,. Since the appli-
cability of Shifrin's tables rests upon the condition
2aa
we conclude that for nearly all these droplets the theory is applicable,
if the light is observed in the usual range of 0. lC < < yx .
The remarkable tendency of the droplets to scatter forward (by a ratio
of 168 to 1) should be of enormous importance. Undoubtedly, this same ten-
dency in snow crystals will turn out to be somewhat less pronounced.
2. The experimental determination of the shape of the scattering phase
function by aerosols. This aspect of the problem is discussed in the work
of Mrs. Pyaskovskaya - Fesenkova (Part B). The results indicate a strongly
forward throwing function, but the effect is apparently smaller than com-
puted by Shifrin. Since the observational work was in part carried out at
high elevations the aerosols may have been in part snow crystals, rather
than drops of water.
3. Studies of the transmission of the atmosphere in the extreme ultra-
violet region accessible without rockets (N> 2950A). This topic has been
discussed observationally and theoretically by Rodionov (Part C). There
appears to be a tendency in the atmosphere to produce what Rodionov calls
an anomalous trap sT)arency for ITV light. Actually, this is not an effect of
A
greater transparency. It is rather an effect of less than the expected in-
crease in absorption at #3260A, for increasing air masses. The results do
not now have any practical value, but they have led to the discovery of an
interesting brood absorption band produced by those aerosols that lie relatively
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close to the surface of the earth. Such a band had been predicted previously
by Haughton and Stratton, and by others.
In view of the fact that in many modern works on visibility the char-
acter of the phase function is ignored (see W.E. Knowles Middleton: Visi-
bility in Meteorology, Second Edition, Toronto, 1947), these Soviet inves-
tigations must be regarded as an important advance. They were probably not
influenced by the work of van'de Huist in America,and Holland (I have found
no references to him in the publications I have examined).
It is clear that these Soviet investigations even now open the way to
some constructive advances that, presumably, could be of great practical
significance. I shall outline only a few of them:
1. Mrs. Fesenkov's method of obtaining a measure of the transparency
coefficient p, on a clear da;-, is the easiest that has as yet been devised,
and its accuracy is somewhat higher than that of the customary procedure.
2. Her deter ination of the T)hase function for terrestrial aerosols
is valuable and should be applied on a large scale in different locations
and under different conditions. As yet, there is no clear correlation be-
tween the nature of the chase function and the character of the aerosols.
For example, it seems to :re that a strongly forwward-throwing function must
be operating in the case of salt particles thrown into the lower atmosphere
by the waves at sea, and esrecially by the surf on a beach. This would re-
sult in a large difference between the blueness of the sky near the sun and
at the point diametrically opposite to the sun (or as neEr to that point
above the horizon ii ; and it makes the angles 9, 9-? , A - 2g...
when ,9 < 11 . The angle of turn (clockwise when e < TC and counterclockwise
when 9 >r is given by
P(K) - (K - 2)1J' + 2 r9? - (K
where 'V is the angle of refraction:
sin cP n
sin 4-1
5. The "width" of each resultant ray is the same as that of the
incident ray. Hence
Io - I(1) + I(2) + I(3) i .....
3. HH:eflected Light (Il)
In this cs.se p(1) - ii - 2 cf
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It is easily seen that the phase function
S(1) ? a2 Io r
sop 4 sip siP
when r = 1 (totally reflecting sphere) the phase function is spherical in
shape
and is therefore independent of c9 . But in the case of water r ~ 1. In
terms of `P and n,
r s V n2 s in2'P -cos
VnT--s-in k +cosIf2
rp
Vn2-sing -
sin ,c if +
n2cos
From this we get for the phase functions
2 nt -cost ~- -
Ssl) a Is 2
n2 - cost
S(1) = a2 Io
p 4 D
4. Light refracted by Droplet
n2 cos }
J
cost 1 F
2
sin 2
2
n2sin 8
2
it
cost ___
2
n2sin (1
0(2)=2(P-w)
This ray can be deflected to a maximum angle of 82.50. All of this light
goes forviard, and is contained within a cone
with angle 82.50.
Out of the incident radiation dF0 the amount that will emerge in this
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form is d2 dFo. At a distance R from the droplet this radiation is spread
over a zone of area
ds(2) - R2 211-sin p(2)dp(2)
ds(2) = R22?c sin p (2)2dq(1 - 1 cos so)
n cos w
The intensity of this light is
I(2) -T7 a2 (?)
ds
d2sin 2 q7
sing l - cos 'r
L n cos q' ,J
90 80 72 94 56 48
We again obtain S(2)) and the total phase function S(2). The phase function
S&P
result'zg from S(2) ? S(1) is shown in Fig. 4.
Fig.4.
5. Several Internal Reflections
The procedure adopted is the same as for one internal reflection. The
amount of light in the K-th case is dF0 d2 r k-2. This is spread over a
zone given by ds(k) - 27r R2 sin R(k)dR(k)and then d8(K) is computed as
(k) d ( 1 ) d . 21 cos d
[i_k
n coswl
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d (k)
changes sign for certain values of cP and at those
It is found that
d
points where it is zero, we observe rainbows.
The value d (k)/dc? appears in the denominator of the intensity
dS k
and this intensity therefore becomes formally infinitely large. The
geometrical theory fails in these directions and we require the formulas
of the wave theory to cope with these difficulties.
6. Connection with the Theory of Rainbows
Table 1 gives the data for successive rainbows, including their pol-
arization which is always large. For successive values of (k) the anglecP
increases, approaching in the limit the value 4P = I1/2. At the same time
the angles of refraction q' also increase, and approach' - 48045'08".
7. Distribution of Energy among Scatterings of Different Degrees
The necessary formulae m-ult from the preceding discussion. Table 2
gives the result.
TABLE 2
1
2
3
4
5
6
7
9
10
s rays
10.111
82.324
6.117
0.962
.264
.102
.048
.025
.015
.009
99.977
p rays
3.074
94.643
1.877
0.255
.076
.029
.015
.008
.005
.003
29.985
Total
6.592
88.483
3.997
0.608
.170
.066
.032
.016
.010
.006
99.981
6.6 per cent is reflected from the drop; 88.5 per cent passes through it;
4 per cent experiences an internal reflection, etc. The rainbows contain
less than 5 per cent.
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8. The Total Phase Function and the Polarization of the Scattered Light
The results are given in a long table. The ratio of light scattered
forward to that backward in 168. Nearly all scattered radiation is con-
tained within a cone of 650.
Fig. 7 shows the final phase function with the positions of the various
Fig. 7
Total phase function for large water droplets.,, The small curve is for the
p rays above.
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TABLE
T(1)
T(2) T(3)
T(4)
T(5) T(6) T(7) T(8) T(9) T(10)
s
s s
3
s a a s a 3
0
1.0000
15.5982
1
0.9610
15.5680
0.0002
0.0071
0.0037
0.0108
2
0.9233
15.4783
0.0002
0.0057
0.0027
0.008/+
3
0.3875
1.3297
0.0002
0.0042
0.0024
0.0066
4
0.8527
1x.1255
0.0002
0.0030
0.0020
0.0050
5
0.3195
14.8686
0.0002
0.0016
0.0027
?
0.0043
6
0.7877
14.5631
0.0002
0.0024
0.0014
0.0038
7
0.7571
14.2134
0.0002
0.0022
0.0012
0.0034
8
0.7277
13.8249
0.0002
0.0020
0.0010
0.0030
9
0.6995
13.4024
0.0002
0.0019
0.0008
002
0
7
.
.
10
0.6723
12.9519
0.0002 0.0018
0.0007
0025
0
.
11
0.6464
12.4785
0.0002 0.0018
0.0006
0.0024
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rr.
able 3 (Continued)
r
o T(1)
S
T(2) T(3)
S S
T(4)
S
T(5) T(6) T(7) T(8) T(9)
S S S S a
T(10)
s
12
0.6215
11.9879
0.0003
0. )n17
0.0005
0.0022
13
0.5976
11.4851
0.0003
0.0017
0.0004
0.0021
14
0.5746
1" .9749
0.0003
0.0016
0.0004
0.0020
15
0.5525
10.4618
0.0003
0.0017
0.003
0.0020
16
0.5314
9.9499
0.0003
0.0018
0.0002
0020
0
17
0.5112
9.4427
0.0003
.
0.0018
0.0250
0.0002
0.0128
0.0020
0.0378
18
0
4917
8.9433
0.0003
0.0018
0.0038
.
0.0002
0.0027
0020
0
0.0065
.
19
0
4731
8.4545
0.0003 0.0018 0.0019
.
0.0002 o.0015
0.0020 0.0034
20
0.4552
7.9784
0.0003 0.0019 0.0007
0.0002 0. ')008
0.0021 0.0015
21
0.4380
7.5167
0.0003 0.0019 0.0002
0.0002 0.0005
0.0021 0.')007
22
0
4216
7.0710
0.0003 0.0020 0.0000
.
0002 0.0004
0
.
0.0022 0.0004
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rs
Table 3 (Continued)
rs
T(l)
T82) Ts3)
T(4)
Ts 5) TJ6) T(7) T88) T(9)
T(10)
23
0.4058
6.6424
0.0003
0.0022
0.0002
0.0003
0.0024
24
0.3907
6.2312
0.0003
0.0023
0.0002
0.0025
25
0.3762
5.8383
0.0003
0.0024
0.0001
0.0025
26
0.3623
5.4637
0.0003
0.0025
0.0001
0.0026
27
0.3490
5.1075
0.0003
0.0026
0.0001
^.0027
28
0.3362
4.7695
0.0003
0.0029
0.0001
0.0030
29
0.3239
4.4494
0.0003
0.0033
0.0001
0.0034
30
0.3122
4.1467
0.0003
0.0037
0.0001
0.0038
31
0.3010
3.8610
0.0003
0.0001
0.0001
0.0041
0.0043
32
0.2901
3.5916
0.0003
0.0002
0.0003
0.0044
0.0049
33
0.2796
3.3380
0.0003 0.0002
0.10010
0.00 47
0.0059
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Table 3 (Continued)
R
T(1)
T(2) T(3)
T(4)
T(5) T(6) T(7). T(8) T(9) T(10)
rs
s
s
s s
s
s s s s s s
34
0.2694
3.0995
0.0003
0.0001
0.0023
0.0053
0.0077
35
0.2601
2.8755
0.0003
0.0001
0.0043
0.0061
0.0105
36
0.2511
2.6651
0.0003
0.0067
0.0069
0.0136
37
0.2425
2.4678
0.0003
0.01o6
0.0082
0.0188
38
0.2339
2.2829
0.0003
0.0151
0.0098
0.0249
39
0.2258
2.1097
0.0003
0.0207
0.0117
0321
0
+
.
40
.2180
''1.9475
0.0003 0.0281
0.0157
0.0438
41
0.2106
1.7958
0.0003 0.0371
0.0222
0
0593
.
42
0.2034
1.6542
0.0003 0.0585
0.0338
0.0923
21
0
0275
43
0.1966
1.5
5
.
0.0856
0.1131
44
0.1900
1.3977
0.0004 0.0156
0.0223
0.0379
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Table 3 (Continued)
rs
T(l)
T(2) Ts 3)
Ts4) T(5)
T(6) T(7) T(8)
T(9) T(10)
45
0.1837
1.2822
0.0004
0.0105
0.0128
0
9233
.
46
0.1776
1.1744
0.0004
0.0065
0.0084
0
0149
.
47
0.1718
1.0739
0.0004
0.0038
0.0058
0.0096
48
0.1662
0.9803
0.0004
0.0025
0.0048
0.0073
49
0.1608
0.8932
0.0004
0.0016
0.0033
0.0049
50
0.1557
0.8121
0.0004
0.0008
0.0030
0.0038
51
0
1507
0.7367
0.0004
0.0005
.
0.0022
0.0027
52
0.1459
0.6668
0.0004
0.0003
0.0019
0.0022
53
0.1414
`0.6018
0.0004
0.0015
54
0.1370
0.5417
0.0004
0.0013
55
0.1327
0.4861
0.0004
0.0010
0.0001
56
0.1287
0.4347
0.0004
0.0009
0.0001
57
0.1248
0.3873
0.0005
0.0008
0.0001
58
0.1210
0.3437
0.0005
0.0006
0.0001
59
0.1174
0.3037
0.0005
0.0005
0.0002
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Table 3 (Continued)
r C T(1)
T(2) T(3)
T(4) T(5)
T(6) T(7) T(8)
T(9) T(10)
s s
S S
S 8
s s s
s s
60
0.1139
0.2670
0.0005
0.0004
61
0.1106
0.2335
0.')005
0.0003
0.0000
0.0002
0.0002
62
0.1074
0.2030
0.0005
0.0003
0.0002
0.0003
?
0
0005
.
63
0.1042
0.1753
0.0005
0.0002
0.0006
0.0004
0.0010
64
0.1013
0.1503
0.0005
0.0002
0.0011
0.0006
0.0017
65
0.0984
0.1278
0.0006
0.0002
0.0018
0.0013
0.0031
66
0.0956
0.1076
0.0006
0.0002
0.0060
0.0039
0.0099
67
0.0930
0.0897
0.0006
0.0002
68
0.0904
0.0738
0.0006
0.0001
69
0.0879
0.0600
0.0006
0.0001
70
0.0855
0.0480
0.0006
0.0001
71
0,0833
0.0377
0.0007
0.0001
72
0.0810
0.0289
0.0007
0.0001
73
0.0789
+0.0216
0.0007
0.0001
74
0.0769
0.0156
0.0008
0.0001
75
0.07/49
0.0108
0.0008
0.0001
76
0.0730
0.0071
0.0008
0.0001
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Table 3 (Continued)
rs - TM T(2) T(a3) T(() T(( ) T(6) T(7) T(8) T() T(10)
77
0.0712
0.0043
0.0008
0.0001
78
0.0693
0.0024
0.0009
0.0001
79
0.0676
0.0011
0.0009
0.0001
80
0.0660
0.0004
0.0009
0.0001
81
0.0644
0.0001
0.0010
0.0000
82
0.0629
0.0000
0.0010
K
83
0.0614
0.0010
84
0.0599
0.0011
85
0.0586
0.0011
86
0.0572
0.0012
87
0.0559
0.0012
88
0.0547
0.0013
89
0.0535
0.0014
90
0.0523
0.0014
91
0.0512
0.0015
92
0.0501
0.0015
93
0.0490
0.0016
94
0.0480
0.0017
95
0.0470
0.0018
96
0.0461
0.0019
97
0.0452
?
0.0020
98
0.0443
0.0022
99
0.0434
0.023
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Table 3 (Continued)
B r8 x T(1) T(2) Tai)
Tao) Tay) Tab) Ta7) Ts8 Tag) T810)
100 0.0426
0.0024
101 0.0418
0.0025
102 0.0410
0.0026
103 0.0402
0.0028
104 0.0395
0.0030
105 0.0388
0.0032
106. 0.0381
0.0034
107 0.0374
0.0037
108 0.0368
0.0040
109 0.0362
0.0043
110 0.0356
0.0047
111 0.0350
0.0051
112 0.0344
0.0002
0.0054
0.0056
113 0.0339
0.0007
0.0055
0.0062
114 0.0333
0.0009
0.0060
0.0069
115 0.0328
0.0010
0.0068
0.0078
116 0.0323
0.0o16
0.0075
0.0091
Approved For Release 1999/0961 : CIA-RbP79-00202A000100040001-2
- 19 -
 Approved For Release 199709/01'6C1\RDP79-00202A000100040001-2
Table 3 (Continued)
13 rs Ta1) .Ta2) Tai) Tao) T35) TS6) T37) T(8) Tag) T910)
117 0.0318
118 0.0313
119 0.0309
120 0.0305
121 0.0301
122 0.0297
123 0.0293
124 0.0289
125 0.0285
126 0.0281
127 0.0277
0.0020
0.0088
0.0108
0.0032
0.0099
0.0131
0.0056
0.0107
0.0163
0.0092
0.0115
0.0207
0.0123
0.0143
0.0266
0.0180
0.0160
0.0340
0.0247
0.0189
0.0435
0.0332
0.0228
0.0560
0.0433
0.0275
0.0708.
0.0553
0.0340
0.0893
0.0701 0.0144
0.0448 0.0091
0.1149 0.0235
Approved For Release 1999/09,Q' :'`,CIA-t[P79-00202A000100040001-2
-20-
 Approved For Release 1+9;9/09/01 clA-RDP79-00202A000100040001-2
Table 3 (Continued)
r s
s
T(1) T(2) T(3)
s $ s
T(4) T35) T(6)
T(7) T(8 T(9) T(10)
128
0.0274
0.0959
0.0629
O.on76
0 0042
?
0.1583
0.0118
?129
0.0271
0.1472
0.0047
6
0.0990
0.002
0.242
0.0073
0.0028
130
0.0268
0.0018
0.0046
o.0016
131
0265
0
.
0.0015
0.0031
0.0006
0.0001
132
0262
0
.
0.0011
0.0017
0.0002
0.0001
133
0.0259
0.0008
0,0010
0001
0
0.0001
134
0.0256
.
o.-)o06
0.0007
0000 0.0001
0
1:35
0253
0
.
.
0.0005
0.0005
0004 0.0001
0
136
0.0250
.
0.0003 0.0001
137
0.0247
138
0.0245
0.9841
0.0003 0.0002
0.8755
1.8596
139
0.0243
0.6229
0.0002 0.0002
0.5040
1.1269
Approved For Release 1999/09
79-00202A000100040001-2
 Approved For Release 1999/09/01 : C
Table 3 (Continued)
RDP79-00202A000100040001-2
N rs g Tsl) T(2)
T(3) Ts T(5) T(6)
Ts 7) T(8) T(e9) T((10) 9 3
140 0.0241
0.5160
0.0002 0.0002
0.3910
0.9070
141
0.0239
0.4215
0.0002 0.0002
0.3210
0.7425
142
0.0237
0.3565
0.0002 0.0003
0.2759
0.6324
143
0.0235
0.3115
0.0002 0.0001
0.2420
0.0004
0.5535
0.0005
144
0.0233
0.2785
0.0002 0.0002
0.2187
0.0005
0.4972
0.0007
145
0.0231
0.2485
0.0001 0.0004
0.1980
0.')007
0.4465
0.0011
146
0.')22_9
0.2168
0.^001 0.0011
0.1797
0.0010
0.3965
0.0021
147
0.022.8
0.1812
0.0001 0.0018
0.1685
0.0016
0
0034
0.3497
.
148 0.0226
0.1655
0.0001 0.0038
0.1570
0.0017
0.3225
0.0055
0224
149 0
0.1420
0.0001 0.0110
.
0.1471
0.0060
0.2891
0.0170
150 0.0222
0.1221
0.0001
0.1398
0.2619
Approved For Release 1999/09/0 ! CIA;RDP79-00202A000100040001-2
- 22 -
 Approved For Release 199 Q9K 1R :, C14-RDP79-00202A000100040001-2
Table 3 (Continued)
rs
TM T2)
S
Ts 3) ls4) T(5) Ts6) T(7) Ts 8) T59) T(10)S
151
0.0220
0.1055
0.1326
0.2381
152
0.0219
0.0905
0.1260
2165
0
.
153
0.0218
0.0757
0.1211
0.1968
154
0.0217
0.0621
0.1162
0.1783
155
0.0216
0.0499
0.1125
0.1624
156
0.0215
0.0383
0.1')80
0.1463
157
0.0214
0.0290
0.1040
0.1330
158
0.0213
0.0202
0.1012
0.1214
159
0.0212
0.0128'
0.0988
0.1116
160
0.0211
0.0070
0.0965
0.1035
161
0.0210
0.0026
0.0939
0.0965
Approved For Release 1999/6J1C 0IA-RDP79-00202A000100040001-2
-23-
 Approved For Release 1999/09/01 : CIA-RDP79-00202A000100040001-2
Table 3 (Continued)
rs
s T(el) T(2)
Ts3) Ts 4) T(s5) T((6) Ts 7) TS 8) Ts9) T(10)
162
0.0209
0.0014
0.0924
0.0938
163
0.0208
0.0004
0.0910
0.0914
164
0.0207
0.0894
165
0.0206
0.0877
166
0.0205
0.0860
167
0.0205
0.0844
168
0.0204
0.0829
169
0.0204
0.0815
170
0.0203
0.0804
171
0.0203
0.0793
172
0.0202
0.0785
173
0.0202
0.0779
174
0.0201
0.0775
175
0.0201
0.0771
176
0.0201
0.0768
177
0.0201
0.0765
178
0.0201
0.0762
179
0.0201
0.0760
180
0.0201
0.0758
Approved For Release 1999/09101 :~ `]A R P79-00202A000100040001-2
- 24-
 Approved For Release 1999/09/01:: CIA-RDP79-00202A000100040001-2
0
rp - T(1)
T(2) TO )
T((4) T(5) T(6) T(7) T(8) T(9)
T(10)
0
1.0000
15.5982
0.0002
1
0.9321
15.5703
0.0002
2
0.8686
15.4875
0.0002
3
0.8095
15.3507
0.0002
4
0.7542
15.1624
0.0002
5
0.7030
14.9254
0.0002
6
0.6550
14.6432
0.0002
7
0.6103
14.3200
0.0002
8
0.5685
13.9604
0.0002
0.5295
13.5690
0.0002
10
0.4931
13.1510
0.0002
11
0.4591
12.7110
0.0002
12
0.4274
12.2542
0.0002
13
0.3978
11.7852
0.0002
14
0.3701
11.3083
0.0002
15
0.3443
10.8276
0.0002
16
0.3202
10.3468
0.0002
17
0.2976
9.8692
0.0002
0.0039
0.0014
0.0053
18
0.2766
9.3976
0.0002
0.0030
0.0004
0.0034
19
0.2570
8.9346 .
0.0002
0.0022
0.0001
0.0023
Approved For Release 1999/09/01 'CIA-RDP79-00202A000100040001-2
- 25 -
 Approved For Release I 999/09/ I R CIA-RDP79-00202A000100040001-2
Table 4 (Continued)
r
T(1)
T(2) T(3)
T(4}
T(5) T(6) T(7) T(8) T(9)
T(1'0)
P
P
P P
P
P P P P P
P
20
0.2386
8.4822
0.0002
0.0013
21
0.2216
8.0420
0.0002
0.0005
22
0.2055
7.6155
0.0002
0.0001
23
0.1906
7.2035
0.0002
24
0.1767
6.8070
0.0002
25
0.1637
6.4263
0.0002
26
0.1516
6.0617
0.0002
27
0.1402
5.7133
0.0002
28
0.1297
5.3809
0.0002
29
0.1198
5.0645
0.0002
30
0.1107
4.7635
0.0002
31
0.1021
4.4777
0.0002
0.0000
32
0.0941
4.2066
0.0002
0.0009
33
0.0867
3.9495
0.0002
0.0025
34
0.0798
3.7060
0.0002
0.0044
35
0.0734
3.4756
0.0002
0.0065
36
0.0673
=.2575
0.0002
0.0095
37
0.0618
3.0513
0.0002
0.0123
0.0000
0.')123
38
0.0566
2.8563
0.0002
0.0144
0.0001
0.0145
39
0.6518
2.6719
0.0002
0.0158
0.0002
0.0160
40
0.0473
2.4977
0.0002
0.0165
0.0003
0.0168
Approved For Release 1999/09101 :`CCI"A- ,DP79-00202A000100040001-2
- 26 -
 Approved For Release 1999/09[0t.--,: clA-Rpp79-00202A000100040001-2
Table 4 (Continued)
r
= T(1)
T(2) T(3)
T(4) T(5)
T(6) T(7) T(8) T(9) T(10)
P
P
P P
P P
P P P P P
41
0.0431
2.3330
0.0002 0.0171
0.0005
0.0176
42
0.0393
2.1774
0.0002 0.0177
0.0014
0.0191
43
0.0357
2.0302
0.0002
0.0088
0.0010
0.0098
44
0.0324
1.8915
0.0002
0.0080
0.0003
0.0083
45
0.0294
1.7599
0.0002
0.0075
0.0001
0
0076
.
46
0.0265
1.6357
0.0002
0.0060
47
0.0239
1.5185
0.0002
0.0044
48
0.0215
1.4074
0.;002
0.0031
49
0.0193
1.3027
0.0002
0.0021
50
0.0172
1.2036
0.0002
0.0014
51
0.0153
1.1101
0.0002
0.0007
52
0.0136
1.0217
0.0002
0.0002
53
0.0120
0.9382
0.0002
54
0.0106
0.3595
0.0002
55
0.0093
0.7852
0.0002
56
0.0081
0.7152
0.0002
57
0.0070
0.6494
0.0002
58
0.0060
0.5874
0.0002
Approved For Release 1999/09/01. Q A tDP79-00202A000100040001-2
 Approved For Release 1999/09/011; CIA-RDP79-00202A000100040001-2
Table 4 (Continued)
r
= T(1)
T(2) T(3)
T(4) T(5) T(6) T(7) T(8)
T(9) T(10)
p
P
p p
P P P P P
P P
59
0.0052
0.5292
0.0002
60
0.0044
0.4747
0.0002
61
0.0037
0.4236
0.0002
62
0.0030
0.3760
0.0001
0.0004
63
0
0025
0.3317
0.0001
0.0008
.
0.0000
0.0008
64
0020
0
0.2906
0.1)001
0.0012
.
0.0000
0.0012
65
0.0016
0.2526
0.0001
0.0016
0.0000
0.0016
66
0.0012
fl.2176
0.0001
0.0017
0.0002
0.0019
67
0.0009
0.1855
0.0001
68
0.0006
0.1564
0.0001
69
0.0004
0.1301
0.0001
70
0.0002
0.1066
0.0001
71
0.0002
0.0857
0.0001
72
0.0000
0.0674
0.0001
73
0.0000
0.0516
0.0001
74
0.0000
0.0383
0.0001
75
0.0000
0.0272
0.0001
76
0.0000
0.0184
0.0001
77
0.0002
0.0116
0.0001
Approved For Release 1999/09/01 CIAO RDP79-00202A000100040001-2
-28-
 Approved For Release 1999/09/01 : CIA-RD"P79-00202A000100040001-2
Table 4 (Continued)
P
r = T(l)
P P
T(2) T(3)
P P
T(4) T(5) T(6) T(7) T(8) T(9) T(10)
P P P P P P P
78
0.0002
0.0066
0.0001
79
0.0004
0.0032
0.0001
80
0.0005
0.0012
0.0001
81
0.0007
0.0003
0.0001
82
0.0008
0.0001
83
0.0010
0.0001
84
0.0012
0.0001
85
0.0015
0.0001
86
0.0017
0.0001
87
0.0020
88
0.0022
89
0.0025
90
0.0027
91
0.0030
92
0.0033
93
D.0036
94
0.0039
95
0.0042
96
0.0045
97
0.00/+8
98
0.0051
99
0.0054
100
0.0057
Approved For Release 1999/09/01 `: ClA2R'DP79-00202A000100040001-2
- 29 -
 Approved For Release 1999109/01 CI RDP79-00202A000100040001-2
Table 4 (Continued)
P r
= T(1) T(2) T(3)
P P P P
T(4) (5) 7(6 T(7) T(8) T(9) T(10)
P yP iP P P P P
101
0.0061
102
0.0064
103
0.0067
104
0.0070
105
0.0073
106
0.0076
107
0.0079
108
0.0082
109
0.0085
110
0.0088
111
0.0091
112
0.0094
113
0.0097
0.0000
114
0.0100
0.0002
115
0.0103
0.0010
116
0.0106
0.0023
117
0.0109
0.0045
118
0.0112
0.0075
119
0.0115
0.0106
120
0.0118
0.0141
121
0.0120
0.0179
122
0.0123
0.0214
123
0.0125
0.02_46
Approved For Release 1999/09/01 C1A-RDP79-00202A000100040001-2
- 30 -
 Approved For Release 1999109101 :-CIA-RDP79-00202A000100040001-2
Table 4(Continued)
P r = T(l) T(2)
T(3)
T(4) T(5) T(6)
T(7) T(8) T(9) T(10)
P P P
P
P P P
P P P P
124
0.0128
0.0276
125
0.0130
0.0300
0.0001
0.0-101
126
0.0133
0.0322
0.0002
0.0324
127
0.0135
0.0340
0.0044
0.0005
0.0007
0.0345
0.0051
123
0.0138
0.0360
0.0042
0.0012
0.0001
0.0372
0.0043
129
0.0140
0.0380
0.0038
0.0029
0.0409
130
0.0143
0.0030
131
0.0145
0.0022
132
0.0147
0.0013
133
0.0149
0.0005
134
0.0151
0.0001
135
0.0153
0.0000
136
0.0155
137
0.0157
138
0.0159
0.1500
0,0090
0.1590
13",
0.0161
0.1498
0.0020
0.1518
Approved For Release 1999/09/01 CIA-RDP79-00202A000100040001-2
-31-
 Approved For Release 1999/09/01 C1A-RDP79-00202A000100040001-2
Table 4 (Continued)
r p T(1) (2) T(3) T(4) T(5) T(6) T(7) T(8) T(9) T(10)
P P P P P P P P P P P
140
0.0163
0.1565
0.0080
0.1645
141
0.0165
0.1620
0.0140
0.1760
142
0.0167
0.1665
0,0195
0.160
143
0.0169
0.1695
0.0001
0.0245
0.1940
144
0.0171
0.1700
0.0003
0.0287
0.1987
145
0.0173
0.1692
0.0009
0.0325
0.2017
146
0.0175
0.1670
0.0365
0.2035
147
0.0176
0.1620
0.0393
0.2013
148
0.0178
0.1560
0.0036
0.0419
0.0001
0.1979
0.0037
149
0.0179
0.1485
0.0042
0.0444
0.0003
0.1929
0.0045
150
0.0180
0.1395
0.0470
0.1865
Approved For Release 1999/09/01 A CIA RDP79-00202A000100040001-2
- 32 -
 Approved For Release 1999/09/01 C14-RDP79-00202A000100040001-2
Table 4 (Continued)
?
f r = T(1) T(2) T(3) 1(4) T(5)
P P P P P P
151 0.0181 0.1295
0.0500
0.1795
152 0.0182 0,1185
153 0.0183
3.54 0.0184
155 0.0135
156 0.0186
157 0.0187
158 0.0188
159 0.0189
160 0.0190
161 0.0191
0.0525
0.1710
0.1069
0.0542-
0.1611
0.0930
0.0560
0.1490
0.0790
0.0500
0.1370
0.0656
0.0596
0.1252
0.05?5
0.061-1
0.1135
0.0405
0.0630
0.1035
0.0300
0.0638
0.0938
0.0215
0.0650
0.0865
0.0120
0.0665
0.0785
T(6) TP7) T(8) T(9) T(10)
Approved For Release 1999/09/01 :' CIA-IDP79-00202A000100040001-2
- 33 -
 Approved For Release 19908/ 1 ,?, IA RDP79-00202A000100040001-2
Table 4 (Continued)
r = T(1) T(2) T(3) T(4) T(5) T(6) T(7} T(8) T(9) T(10)
P P P P 'P 'P P P P P P
162 0.0192
163 0.0193
164 0.0194
165 0.0195
0.0055
0.0680
0.0735
0.0`)17
0.0690
0.0707
0.0001
0.0700
0.0701
0.0000
0.0703
0.0703
166 0.0196 0.0707
167 0.0197 0.0712
168 0.0197 0.0718
169 0.0198 0.0725
170 0.0198 0.0732
171 0.0199 0.0738
172 0.0199 0.0744
173 0.0200 0.0749
174 0.0200 0.0751
175 0.0200 0.0753
176 0.0200 0.0754
177 0.0200 0.0755
178 0.0200 0.0756
179 0.0201 0.0757
180 0.0201 0.0758
Approved For Release 1999/09101 CIA-RDP79-00202A000100040001-2
 Approved For Release 1999709/.01::.: Ii-RDP79-00202A000100040001-2
TABLE 5
Ts
Tp
T .Ts +Tp
16.5984
16.5984
33.1968
0.0000
1
16.5400
16.5026
33.0426
.0011
2
16.4102
16.3563
32.7665
.0016
3
16.2240
16.1604
32.3844
.0020
4
15.9834
15.9168
31.9002
.0021
5
15.6926
15.6286
31.3212
.0020
6
15.3548
15.2984
30.7532
.0018
7
14.9741
14.9305
29.9046
.0014
8
14.5558
14.5291
29.0849
.0009
9
14.1048
14.0987
28.2035
.0002
10
13.6269
13.6443
27.2712
-0.0006
11-
13.1275
13.1703
26.2978
- .0017
12
12.6119
12.6518
25.2937
- .0028
13
12.0851
12.1832
24.2683
- .0040
14
11.5518
11.6786
22.2304
- .0055
15
11.0166
11.1721
22.1887
- .0070
16
10.4836
10.6672
21.1508
- .0087
17
9.9940
10.1723
20.1663
- .0088
18
9.4438
9.6778
19.1216
- .0122
19
8.9333
9.1941
18.1274
- .0144
20
8.4375
8.7223
17.1598
- .0166
21
7.9578
8.2643
16.2221
- .0189
22
7.4955
7.8213
15.3168
- .0213
23
7.0512
7.3943
14.4455
- .0238
24
6.6249
6.9839
13.6088
- .0264
25
6.2174
6.5902
12.8076
- .0291
26
5.8290
6.2135
12.0425
- .0319
27
5.4596
5.8537
11.3133
- .0348
28
5.1090
5.5107
10.6197
- .0378
29
4.7770
5.1845
9.9615
- .0409
30
4.4630
4.,8744
9.3374
- .0441
31
4.1666
4.5800
8.7466
- .0473
32
3.8869
4.3018
8.1887
- .0507
33
3.6238
4.0389
7.6627
- .0542
34
3.376
3.7904
7.1673
- .0577
35
3.1463
3.5557
6.7020
- .0611
36
2.9301
3.3345
6.2646
- .0646
37
2.7294
3.1256
5.8550
- .0677
38
2.5420
2.92'76
5.4696
- .0707
39
2.3682
2.7399
5.1081
- .0728
40
2.2096
2.5620
4.7716
- .0738
41
2.0660
2.3939
4.4599
- .0735
42
1.9502
2.2360
4.1862
- .0683
43
1.8315
2.0759
3.9074
- .0628
44
1.6260
1.9324
3.5584
- .0861
r
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 Approved For Release 1999/09/01 CIA-FDP79-00202A000100040001-2
Table 5.(Continued)
TS
TP
T = Ts + TP
P
45
1.4896
1.7971
3.2867
-0.0935
46
1.3673
1.6684
3.0357
.0992
47
1.2557
1.5470
2.8027
.1040
48
1.1542
1.4322
2.5864
- .1075
49
1.0593
1.3243
2.3836
- .1115
50
0.9720
1.2224
2.1944
- .1141
51
.8905
1.1263
2.0168
- .1169
52
.8153
1.0357
1.8510
- .1191
53
.7451
0.9504
1.6955
- .1210
54
.6804
.8703
1.5507
- .1225
55
.6203
.7948
1.4151
- .1235
56
.5648
.7235
1.2883
- .1231
57
.5135
.6566
1.1701
.1223
58
.4659
.5936
1.0595
.1205
59
.4223
.5346
0.9569
- .1173
60
.3820
.4793
.8613
- .1130
61
.3451
.4276
.7727
- .1068
62
.3117
.,795
.6912
- .0981
63
.2812
.3351
.6163
- .0874
64
.2540
.2939
.5479
- .0728
65
.2301
.2559
.4860
- .0530
6~.
.2139
.2208
.4347
.0159
67
.1835
.1865
.3700
.0083
68
.1649
.1571
.3220
.0242
69
.1486
.1306
.2792
.0645
70
.1342
.1069
.2411
.1132
71
.1218
.0860
.2078
.1723
72
.1107
.0675
.1782
.2424
73
.1013
.0517
.1530
.3242
74
.0934
.0384
.1318
.4173
75
.0866
.0273
.1139
.5206
76
.0810
.0185
.0995
.6281
77
.0764
.0119
.0883
.7305
78
.0727
.0069
.0796
.8266
79
.0697
.0037
.0734
.8992
80
.0674
.0018
.0692
.9480
81
.0655
.0011
.0666
.9670
82
.0639
.0009
.0648
.9722
83
.0624
.0011
.0635
.9654
84
.0610
.0013
.0623
.9583
85
.0597
.0016
.0613
.9478
86
.0584
.0018
.0602
.9402
87
.0571
.0020
.591
.9323
88
.0560
.0022
.0582
.9244
89
.0549
.0025
.0574
.9129
90
.0537
.0027
.0564
.9043
.;Yp
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- 36 -
 Approved For Release I 999/ f0'fl .:'.clA- tDP79-00202A000100040001-2
Table 5 (Continued)
Ts
Tp
T=Ts+TP
91
0.0527
0.0030
0.0557
0.8923
92
.0516
.0033
.0549
.8798
93
.0506
.0034
.0542
.8672
94
.0497
.0039
.0536
.8545
95
.0488
.0042
.0530
.8415
96
.0480
.0045
.0525
.8286
97
.0472
.0048
.0520
.8154
98
.0465
.0051
.0516
.8023
99
.0457
.0051
.0511
.7886
100
.6450
.0057
.0507
.7751
101
.0443
.0061
.0504
.7579
102
.0436
.0064
.0500
.7440
103
.0430
.0067
.0497
.7304
104
.0425
.0070
.049,5
.7172
105
.0420
.0073
.0493
.7038
106
.0415
.0076
.0491
.6904
107
.0411
.3079
.0490
.6776
108
.0408
.0082
.0490
.6653
109
.0405
.OO85
.0490
.6531
no
.0403
.0088
.0491
.6415
111
.0401
.0091
.0492
.6301
112
.0400
.0094
.0494
.6194
113
.0400
.0097
.0497
.6096
114
.0402
.0102
.0504
.5952
115
.0406
.0113
.0519
.5645
116
.0414
.0129
.0543
.5249
117
.0426
.0154
.0580
.4690
118
.0444
.0187
.0631
.4073
119
.0472
.0221
.0693
.3622
120
.0512
.0259
.0771
.3281
121
.0567
.0299
.0866
.3095
122
.0637
.0337
.0974
.3080
123
.0728
.0371
.10c'9
.3258
124
.0849
.0404
.1253
.3551
125
.0993
.0431
.1424
.3947
126
.1174
.0457
.1631
.4396
127
.1661
.0531
.2192
.5155
128
.1975
.0553
.2528
.5625
129
.2806
.0587
.3393
.6540
130
.0314
.0173
.0487
.2895
131
.0296
.0167
.0463
.2894
132
.0280
.0160
.0440
.2727
133
.0270
.0154
.0424
.2735
134
.0264
.0152
.0416
.2692
135
.0259
.0153
.0412
.2572
136
.0255
.0156
.0410
.2439
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_ 37 -
 Approved For Release 1999/0(9/&t: C.b - DP79-00202A000100040001-2
Table 5 (Continued)
Tp
T - Ts+TP
137
0.0251
0.0157
0.0408
0.2303
138
1.8846
.1749
2.0595
.8302
139
1.1516
.1679
1.3195
.7455
140
0.9315
.1808
1.1123
.6749
141
.7668
.1925
0.9593
.5986
142
.6566
.2027
.8593
.5283
143
.5777
.2110
.7887
.4649
144
.5214
.2161
.7375
.4139
145
.4708
.2199
.6907
3632
146
.4216
.2229
6445
.
.3083
147
.3760
.2218
.5978
.2579
148
.3507
.2194
.5701
.2478
149
.3286
.2153
.5439
2083
150
.2842
.2045
.4887
.
.1631
151
.2601
.1976
.4577
.1365
152
.2385
.1892
.4277
1152
153
.2187
.1794
.3981
.
.0987
154
.2001
.1674
.3675
0890
155
.1841
.1555
.3396
.
0842
156
.1679
.1438
.3117
.
0780
157
.1545
.1322
.2867
.
0778
158
.1428
.1223
.2651
.
.0774
159
.1329
.1127
.2456
0762
160
.1247
.1055
.2302
.
.0834
161
.1176.
.0075
.2152
.0929
162
.1148
.0927
.2075
1065
163
.1123
.0900
.2023
.
1102
164
.1102
.0895
.1997
.
1036
165,
.1083
.0898
.1981
.
0934
166
.1065
.0903
.1968
-
0824
167
.1342
.0909
.1958
.
0715
168
.1033
.0915
.1948
.
0605
169
.1019
.0923
.1942
.
.0494
170
.1007
.0930
.1937
0398
171
.0906
.0937
.1933
.
.0305
172
.0987
.0943
.1930
0228
123
.0981
.0949
.1930
.
0166
174
.0976
.0951
.1927
.
0130
175
.0972
.0953
.1925
.
0098
176
.0969
.0954
.1923
.
.0078
177
.0966
.0955
.1921
.0057
178
.0963
.0956
.0919
.0036
179
.0961
,0958
.0919
.0015
180
.0959
.0959
.1918
.0000
Approved For Release 1999/09/01 CIA-R DP79-00202A000100040001-2
 Approved For Release 1999/09101 : CIA-RDP79-00202A000100040001-2
E.V. Pyaskovskaya - Fesenkovas Some Data on the Optical Properties of
Atmosphere under Mountain Conditions
(Astronomicheddy Zhurnal, T.29, Vyp. 3,
p. 313, 1952).
The observations were made in several locations in the Soviet Union
with a visual surface photometer constructed by V.G. Fesenkov.. The obser-
vations give directly the ratio of the surface brightness of a given region
in the sky to the brightness at the zenith. If the illumination from the
sun on a unitsarea at right angles to the rays, outside the atmosphere, is
Eo .o and at the place of observations, E 08m then
E0i'm = E0so pm
By measuring the illumination with the photometer we obtain directly
= B/E o IM
Hence, in stilbs,
B =E0 o pm d
The quantity E (DO is considered as a constant
i
E 0,0 = 13,000 lux = 13 phot.
at A ~ ,, 546 u=p.
The author discusses four methods of determining p with a precision of
one per cent. The first three are her own.
1) The brightness of the area around the sun increases from sunrise
until it reaches a certain maximum value at zenith distance Zo , after which
it again decreases. At the time of naxinium brightness In p = 1
m max
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 Approved For Release 1999/09/01: CIA-RDP79-00202A000100040001-2
where m (max) is. the air mass at the appropriate moment. The maximum
brightness occurs at that moment at which the optical thickness of the at-
mosphere is equal to one.
2) Let the phase function of scattering in the atmosphere bey. f (e)
and let
R
= 2'Kju sine de
0
be the luminous flux scattered in all directions, then'j' is the optical
thickness of the atmosphere and p = e . The values of # are found from
the observations at different angular distances 8 from the sun, at the sun's
elevation above the horizon:
y 6f (9) = Boom m
o om
The phase function is normalized to give f (900) = 1. This method takes
account only of first-order scattering processes.
3) An empirical formula based upon a large number of observations
gives
p = 0.973 - 9.80j (60?)
wherejU is measured at 9 - 600. All that is required here is one measure-
ment of the sky, on the almucantarat of the sun, at 6 . 600; and one com-
parison of a surface with known albedo with the zenith sky.
Al alternative formula for 9 = 900,
p = 0.977 - 14.08y (90?)
is less accurate. Both expressions apply only to 476