RESEARCH ON WEATHER MODIFICATION

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP83-00423R000800500002-6
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 2
• Document Creation Date: November 9, 2016
• Document Release Date: November 13, 1998
• Sequence Number: 2
• Content Type: REPORT

proved For Release 1999109/1 04;3ROO0800500002-6
COUNTRY Germany
SUBJECT Research on Weather Modification
PLACE ACQUIRED
----
(BY SOURCE)
25X1A6a
Supplement to:
DATE ACQUIRED
Responsive to:
(BY SOURCE)
DATE (OF INFO)
1952
Pages 2
States, within
as amended. Its transmission or re
unauthorized person is prohibited by law.
prohibited.
contents to or receipt by an
25X1A2g
information affecting the national defense of the United
le 18, Sections 793 and 794, of the U.S. Code,
ort is
This UNEVALUATED INFORMATION is supp g A?gthe possible interest of your analysts.
It does not warrant dissemination by
25X1X6
Source or Clarifying Statement:
.1.
25X1X6
"Heinz Theile (Inst Erdolforshung, Hannover, Germany) Erdol u Kohle 5,
Ii.07-12(1952). - Formation of fog in supersaturated vapor-gas mixtures
takes place only when the heat transfer from the vapor-gas stream exceeds
the diffusion of molecules to the walls. According to Hansen (cf C A 43,
lie) the ratio of the temperature coefficient of heat transfer to the
diffusion coefficient is in the first approximation equal to the square root of
the ratio of the molecular weight of vapor and gas. With the exception of
H2O, the condensable constituent will always have a higher molecular weight
than the carrier gas. Since supersaturation alone does not suffice to cause
fog formation, the question arose whether the spontaneous formation of nuclei
during the cooling of vapor-gas mixtures is sufficient for fog formation.
Hexane-N and furfural-N mixtures produced fogs when previously heated above
200 and 300 degrees 5resumably Centigrad7, respectively. Addition of two
per cent Oxygen to the hexane-N mixture at 500 to 570 degrees was particularly
effective. Experiments indicated that foreign nuclei were necessary for the
production of fog. Attempts to precipitate the nuclei in previously heated
furfural-N mixtur s electrostatically were unsuccessful because the diameter
was less than 14- cm. Filtering the gas stream through closely packed cotton.
or quartz wool was effective in most cases either in diminishing or preventing
fog formation. Turbul.ance_removed hexane fog completely. The rotating metal-
band (cf C A 32, 73103) method removed allyl bromide fog from hexane but did
so only in part from undisturbed furfural. The rotating band method is not
considered practical. It is shown diagrammatically that a 'superimposed heat
stream' (addition of heat to the vapor-gas stream) prevents supersaturation
completely. With proper arrangement (example shown) the heat capacity of the
vapor-gas mixture can be utilized and may often suffice to prevent supersatura-
tion."
within the USA of CIA and the Intelligence components
of State, Army, Navy, anr~ it + +^ be transmitted overseas
without the concurrence of the originating office-U707
of the Office of Collection and Dissemination, CIA.
Approved For Release 1999/09/10 : CIA-RDP83-00423R000800500002-6
wow I ~ ZkA 11%1pY
 Approved For Release 1999/09/10 : CIA-RDP83-00423R000800500002-6
-2 -
2. This is an example of basic physics research which can be applied to
meteorology and weather modification. The experiments were performed in
physics laboratories, but they could readily be applied to natural atmosphere
with essentially the same conclusions.
Approved For Release 1999/09/10 : CIA-RDP83-00423R000800500002-6