Weather modification techniques have been attempted throughout history for various purposes. Common methods include cloud seeding to increase rain or snow. Weather modification was also attempted militarily, such as Operation Popeye which aimed to prolong the monsoon season in Vietnam. While many countries practice weather modification today through cloud seeding, weather modification in warfare is banned by an UN convention.

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WEATHER MODIFICATIONS
A weather modification (also known as weather control) is the act of
intentionally manipulating or altering the weather. The most common form of
weather modification is cloud seeding, which increases rain or snow, usually
for the purposeof increasing the local water supply. Weather modification can
also havethe goal of preventing damaging weather, such as hail or hurricanes,
fromoccurring; or of provoking damaging weather against the enemy, as a
tactic of military or economic warfarelike Operation Popeye, whereclouds
were seeded to prolong the monsoon in Vietnam. Weather modification in
warfarehas been banned by the United Nations under Environmental
Modification Convention.
HISTORY
A popular belief in northern Europethat shooting prevents hail caused many
agricultural towns to fire cannons withoutammunition. Veterans of the Seven
Years'War, Napoleonic wars, and the American Civil War reported that rain fell
after every large battle. After their stories were collected in War and Weather,
the United States Department of War in the late 19th century purchased
$9,000 of gunpowder and explosives to detonate them in Texas. The results of
the test, supervised by Robert Dyrenforth, wereinconclusive.
In November 1955, theThailand Royal Rainmaking Project was initiated by
King Bhumibol Adulyadej. He discovered that many areas faced the problem
of drought. Over 82 percent of Thai agriculturalland relied on rainfall. Thai
farmers werenot able to grow crops for lack of water. The royalrainmaking
projectdebuted on 20 July 1969 at his behest, when the first rainmaking
attempt was made at Khao Yai National Park. Dry ice flakes werescattered
over clouds. Reportedly, somerainfall resulted. In 1971, thegovernment
established the Artificial Rainmaking Research and Development Projectwithin
the Thai Ministry of Agricultureand Cooperatives.
In January 2011, severalnewspapers and magazines, including the UK's Sunday
Times and Arabian Business, reported that scientists backed by the

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governmentof Abu Dhabi, the capital of the United Arab Emirates, had created
over 50 artificial rainstorms between July and August2010 near Al Ain, a city
which lies close to the country's border with Oman and is the second-largest
city in the Abu Dhabi Emirate. The artificial rainstorms weresaid to have
sometimes caused hail, gales and thunderstorms, baffling localresidents.The
scientists reportedly used ionizers to create the rainstorms, and although the
results are disputed, the large number of times it is recorded to have rained
right after the ionizers were switched on during a usually dry season is
encouraging to those who supportthe experiment.
CLOUD SEEDING
Cloud seeding is a type of weather modification that aims to change the
amount or type of precipitation that falls from clouds by dispersing substances
into the air that serve as cloud condensation or ice nuclei, which alter the
microphysicalprocesses within the cloud. The usualintent is to increase
precipitation (rain or snow), buthail and fog suppression arealso widely
practised in airports whereharsh weather conditions areexperienced.
"China is launching the world's largestweather-controlmachine, with the
ability to modify the weather in an area similar to the size of Alaska. China has
never shied away fromdoing things on a massivescaleand this is yet another
example of the Chinese governmentworking on an unprecedented
scale".China estimates it to produceup to 10 billion cubic meters of rainfall
each year. For comparison, morethan 30 countries get less than 10 billion
cubic meters of precipitation per year.
Saudi Arabia has been cloud seeding sincethe 2000s and aims to increase
rainfall by 15-30% per year. The material used is: potassium chloride, sodium
chloride, magnesium, and other materials.

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Storm prevention
ProjectStormfury was an attempt to weaken tropical cyclones by flying aircraft
into storms and seeding the eyewall with silver iodide. The projectwas run by
the United States Governmentfrom 1962 to 1983. A similar project using soot
was run in 1958, with inconclusiveresults. Various methods have been
proposed to reduce the harmfuleffects of hurricanes. MosheAlamaro of the
Massachusetts Instituteof Technology proposed using barges with upward-
pointing jet engines to trigger smaller storms to disruptthe progress of an
incoming hurricane; critics doubtthe jets would be powerfulenough to make
any noticeable difference.
Alexandre Chorin of the University of California, Berkeley, proposed dropping
large amounts of environmentally friendly oils on the sea surface to prevent
droplet formation. Experiments by Kerry Emanuel of MITin 2002 suggested
that hurricane-forcewinds would disruptthe oil slick, making it ineffective.
Other scientists disputed the factual basis of the theoretical mechanism
assumed by this approach.
The Florida company Dyn-O-Matand its CEO, Peter Cordani, proposed the use
of a patented productit developed, called Dyn-O-Gel, to reduce the strength of
hurricanes. The substanceis a polymer in powder form (a polyacrylic acid
derivative) which reportedly has the ability to absorb 1,500 times its own
weight in water. The theory is that the polymer is dropped into clouds to
remove their moistureand force the storm to usemore energy to movethe
heavier water drops, thus helping to dissipatethe storm. When the gel reaches
the ocean surface, it is reportedly dissolved. Peter Cordani teamed up with
Mark Daniels and Victor Miller, the owners of a governmentcontracting
aviation firm AeroGroup which operated ex-military aircraftcommercially.
Using a high altitude B-57 Bomber, AeroGroup tested the substancedropping
9,000 pounds fromtheB-57 aircraft's large bomb bay disbursing it into a large
thunderstormcell justoff the east coast of Florida. The tests were documented
on film and made international news showing the storms weresuccessfully
removed on monitored Doppler radar. In 2003, theprogram was shutdown
because of political pressurethrough NOAA. Numerical simulations performed

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by NOAA showed however that it would not be a practical solution for large
systems like a tropical cyclone.
Hail cannons have been used by some farmers sincethe 19th century in an
attempt to ward off hail, but there is no reliable scientific evidence to confirm
their effectiveness. Another new anti-hurricane technology is a method for the
reduction of tropical cyclones'destructiveforce – pumping sea water into and
diffusing it in the wind at the bottom of such tropical cyclone in its eye wall.
Hurricane modification
NOAA published a page addressing various ideas in regards to tropical cyclone
manipulation.
"How to stop a hurricane"[21] explored various ideas such as:
.Using lasers todischarge lightning instorms whichare likely tobecome
hurricanes
.Pouring liquidnitrogenontothe seato deprive the hurricane of heat
energy.
.Creating soot to absorbsunlight and change air temperature andcreate In
the military convectioncurrents inthe outer wall.
In the military
Operation Popeye was a highly classified operation run by the US military in
1967-1972.Thepurposewas to prolong Monsoon in Southeast Asia. The
overwhelming precipitation successfully disrupted the tactical logistics of
Vietnamese army. Operation Popeye is believed as the first successfulpractice
of weather modification technology in warfare. After it was unveiled, weather

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modification in warfarewas banned by the EnvironmentalModification
Convention (ENMOD).
In "Benign Weather Modification" published March 1997, Air ForceMajor
Barry B. Coble superficially documents the existence of weather modification
science wherehe traces the developments that have occurred, notably, in the
hands of the Pentagon and CIA's staunchestideological enemies.
 The first scientifically controlledandmonitoredeffort generally
recognizedby the meteorological community as constituting weather
modificationoccurredin1948. WhenDr. Irving Langmuir first
experimentedwithartificially seeding clouds toproduce rain, his
experimentsshowedpositive results –sparking tremendous interestin
the fieldnearly overnight.
 Many countries throughoutthe world practice weather modification.
The Russians havelong been interested in using weather modification as
a way to control hail.
 The Chinese recognize the value of weather modification and believe
that the US military continues to use weather as a weapon.
In religion and mythology
Magical and religious practices to controlthe weather are attested in a variety
of cultures. In ancient India it is said that yajna or vedic rituals of chanting
mantras and offering were performed by rishis to bring sudden bursts of rain
fall in rain starved regions. SomeIndigenous Americans, likesomeEuropeans,
had rituals which they believed could induce rain. The Finnish people, on the
other hand, were believed by others to be able to control weather. As a result,
Vikings refused to take Finns on their oceangoing raids. Remnants of this
superstition lasted into the twentieth century, with someship crews being
reluctant to accept Finnish sailors.

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In Greek mythology, Iphigenia was offered as a human sacrifice to appeasethe
wrath of the goddess Artemis, who had becalmed the Achaean fleet at Aulis at
the beginning of the Trojan War. In Homer's Odyssey, Aeolus, keeper of the
winds, bestowed Odysseus and his crew with a gift of the four winds in a bag.
However, the sailors opened the bag while Odysseus slept, looking for booty
(money), and as a result wereblown off courseby the resulting gale. In ancient
Rome, the lapis manalis was a sacred stone kept outside the walls of Rome in a
temple of Mars. When Rome suffered from drought, the stone was dragged
into the city. The Berwick witches of Scotland were found guilty of using black
magic to summon storms to murder King James VI of Scotland by seeking to
sink the ship upon which he travelled.[40] Scandinavian witches allegedly
claimed to sell the wind in bags or magically confined into wooden staves; they
sold the bags to seamen who could release them when becalmed. In various
towns of Navarre, prayers petitioned Saint Peter to grant rain in time of
drought. If the rain was not forthcoming, the statue of St Peter was removed
fromthe church and tossed into a river.
In the Jewish Scriptures, otherwiseknown as theOld Testament, it is recorded
that Elijah in the way of judgement, told King Ahab that neither dew nor rain
would fall until Elijah called for it. Itis further recorded that the ensuing
droughtlasted for a period of 3.5 years at which time Elijah called the rains to
come again and the land was restored.TheChristian Bible in the New
Testament records Jesus Christcontrolling a storm by speaking to it.
In Islam,SalatAl-Istisqa’ (Prayer for Rain)is taken as recoursewhen seeking rain
from God during times of drought.
In literature
Frank Herbert's Duneseries features weather control technology, mainly in the
planets of Arrakis, wherethetechnology is used to assurefor privacy from
observation and in order to hide from the Imperium their true population and

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their plans to terraformthe planet, and in Chapterhouse, wherethe Bene
Gesseritintend to turn the planet into a desert.
References
 Gelt, Joe. "Weather Modification: A Water ResourceStrategy to be
Researched, Tested Before Tried". University of Arizona. Archived from
the original on June 5, 1997. Retrieved April 17, 2012.
 Ley, Willy (February 1961). "Let's Do Something About the Weather". For
Your Information. Galaxy Science Fiction. pp. 72–84.
 Langmuir, Irving (December 13, 1948). FinalReport: Project Cirrus
(Report No. PL 140 ed.). General Electric Research Laboratory. p. 14.

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