pao e
So
C

ee

—

C.

for the three different charges are the same where

dq

W 173, and d«=

depth of burial of charge in feet, W = weight of TNT in lbs,

If explosion

cloud density is some function of the amount of high explosive used, then
it may be that cloud density is also a function of the equivalent energy

yield of atomic or thermonuclear weapons,

Of course there is no method

of determining the magnitude of such a function except to say that probably

cloud density increases with energy yield of the bomb by some factor,

In this report it will be assumed that the cloud density for high
yield atomic or thermonuclear bombs in the order of 10 megatons of energy

yield, exploded at scaled depths underground would be approximately forty
times the cloud density for 1,0 scale TNT explosion mentioned above, and
the cloud density for surface explosions would be approximately thirty
times the cloud density of the aboveementioned TINT explosion. It will be
assumed that the clouds from JANGLEjunderground and JANGLE-surface shots
have the same cloud density as that for the 1.0 scale TNT shot mentioned

above.

Under this assumption the stabilized cloud from 1,2 KT JANGLE-

underground shot would weigh approximately 4 x 10° lbs., and the JANGLE}surface cloud would weigh approximately 3 x 109 lbs. This means that
~

for a 10 megeton weapon exploded at_scaled depth underground, the cloud

would weigh approximately 1.6 x 10/1 lbs. and for a surface burst the
total cloud weight would be approximately 9 x 1040 lbs.

It will be

further assumed that the numerical median particle diameter in the cloud
is 0.6 micron,
IV.

REDUCTION OF SOLAR RADIATION BY THE LAYSR OF DUST ALOFT

In the Preliminary Report, Rayleigh's Equetions for diffuse reflection
and random scatter were used. These equations will be mentioned here
again so that a ready comparison could be made with the more rigorous
treatment of the subject by Mie, Also a computational error was made by

Humphreys (1), and this will also be discussed below,
A.

Rayleigh's Equations
1.

Equation for Random Scatter

If dust particles are emaller than the wave length
of visible light then according to Humphreys' text the
following equation applies:
-hy
Ey =F eC

where
h®

=

24 17

trWmexrzeeaenenwneananw aa o Equation 1

3

2

K' - K
Pear

Ye
a

= + = -Equation
Equation" 2

K' = dielectric constant dust particles
K = cielectric constant of medium

V = volume of each particle

_

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