Evening star. [volume] (Washington, D.C.) 1854-1972, 1955-03-21
A-BIusts Found to Have
No Effects on Weather
MeteoroIogists Complete
Extensive Study Of Subject
By Themes R. Henry

oy tnOmoS n. 0eHty
Meteorologists are unable to observe
any consistent effect of atomic explo-
sions on weather.
The atomic bomb is blamed for about
everything these days, with some justi-
fication In many cases. but apparently
1t is not guilty of causing droughts, cy-
clones, floods, heat waves, and cold
waves.
At least there is no way Of proving 1t
guilty, according to Drs. L. Machta and
D. L. Harris of the United States
Weather Bureau after an intensive
study and a survey of the opinions Of
the countrys foremost weather experts.
First, they say. there is no reason why
a test explosion should change weather.
Second, the weather hasn't really
changed.
Known Possibilities
Theoretically, they point out, there
are three known possibilities. First is
cloud seeding" the mechanism of ar
tificially produced rainfall. by the fine
particles Showered into the upper air
by bomb explosion. Brief local show
ers have, in fact, followed some explo-
sions. But, they point out, "the only
debris added to the air by bomb ex-
plosion high above the ground is the
material contained in the bomb itself
and only a small fraction of this is
thought to be effective as ice nuclei"
essential for rainmaking. From the Me-
vada tests it has been found that SO per
cent of the debris from a low altitude
explosion consists of soil particles sucked
I'm hNYf tho riciv7r cloud CoYvnn1nc af THE
dust have been sent to two laboratories
to be tested as ice nuclei. Both have
reported completely negative findings.
Second. bomb explosion alters some
what the electrical conductivity Of the
atmosphere. especially in the immediate
vicinity. This could very well have a
very small weather effect. the experts
agree-less lightning accompanying
thunderstorms.
Third, decreasing the amount of
solar radiation falling on the earth by
setting up curtain of dust. This might.
If the curtain were thick enough. tenn
porarily decrease the earth's tempera-
ture. This has happened in the past
after some titanic volcanic explosions,
with resulting summarizes years" and
dark days. However. the amount Of
dust from q bomb explosion, they cal
culate, is far too small to produce any
such effect.
Energy in Atmosphere.
An enormous amount Of energy Is
thrown into the atmosphere by such
an explosion and, the experts admit,
too little is known to deny absolutely
that a disequilibrium may be set up
which could have some effect on
weather. But this energy is relatively
small compared with that present all
the time. For example, the amount Of
sunshine falling on one square mile
of Nevada on an average spring day
is equivalent to the energy of two
bombs The energy released by the con-
densation of water in the average thun-
derstorm is equal to about IS bombs.
All this would not mean much, how
ever, If the weather actually had
changed materially, for there still is
a lot about weather nobody under
stands. In fact, however, it has not
changed.
Increased frequency of tornadoes is
the charge made most often. There
were 200 more reported in 1858 than
in any other year on record, and 1854
was close runnerup. But there have
been other tornado years. long before
the atomic bomb, and it is highly I'M
likely that the increase was actual. It
was simply case of more observers and
more reports. In other years it is likely
that a great number of tornadoes. oc-
curing IN open country, never were
reported.
Property damage and loss Of life
from tornadoes actually was somewhat
less than in several other years.