Weather modification is when people try to change the weather on purpose. A common method is cloud seeding, which helps make more rain or snow, often to increase the amount of water available in an area. Weather modification can also aim to stop harmful weather, such as hail or hurricanes, from happening. In some cases, it has been used to cause bad weather to harm an enemy, like during Operation Popeye, where clouds were seeded to make the monsoon in Vietnam last longer. The United Nations has banned the use of weather modification in warfare through the Environmental Modification Convention.
History
A common belief in Northern Europe was that shooting could stop hail, which led many farming towns to fire cannons without bullets. Soldiers who fought in the Seven Years' War, Napoleonic Wars, and the American Civil War said that rain often fell after large battles. After these stories were shared in a book called War and Weather, the United States Department of War bought $9,000 worth of gunpowder and explosives in the late 1800s to explode them in Texas. The goal was to turn water vapor into rain. The results of the test, led by Robert Dyrenforth, were unclear.
In the 1950s, Wilhelm Reich tested a method called cloudbusting. The outcomes of these experiments are debated and were not widely supported by scientists.
In November 1954, the Thailand Royal Rainmaking Project (Thai: โครงการฝนหลวง) was started by King Bhumibol Adulyadej. He noticed that many areas in Thailand had droughts. More than 82% of farmland in Thailand depended on rain. Farmers struggled to grow crops because of a lack of water. The royal rainmaking project began on July 20, 1969, at Khao Yai National Park, where dry ice pieces were spread over clouds. Some rain reportedly fell. In 1971, the Thai government created the Artificial Rainmaking Research and Development Project under the Ministry of Agriculture and Cooperatives.
In January 2011, news outlets like the UK's Sunday Times and Arabian Business reported that scientists working with the government of Abu Dhabi, the capital of the United Arab Emirates, created more than 50 artificial rainstorms near Al Ain between July and August 2010. These rainstorms sometimes caused hail, strong winds, and thunderstorms, confusing local people.
Before the 2008 Beijing Olympic Games, the Chinese government stated that they could influence rainfall to some degree and that the Games would not be affected by poor weather. To achieve this, they created a government office called the Beijing Weather Modification Office, which operates under the national weather control office.
Cloud seeding
Cloud seeding is a method used to increase rainfall. It involves spreading tiny particles, such as silver iodide, into clouds to influence their growth and encourage more rain. This technique only works if there is already water vapor in the air. Some people argue that reported successes happen in situations where rain would have occurred naturally. Cloud seeding is used in many countries that often experience droughts, including the United States, China, India, and Russia. In China, some areas rely heavily on cloud seeding, and there is concern it may be used to reduce air pollution in dry, polluted places like Beijing. In the United States, cloud seeding has been used in mountainous regions such as the Rocky Mountains and Sierra Nevada since the 1950s.
Project Cirrus was an experiment from 1947 to 1952 led by General Electric with support from the United States Air Force. Scientists tried to create snowstorms and seed hurricanes using silver iodide. While General Electric reported some positive results, their experiments were widely debated.
The United Arab Emirates has used cloud seeding since the 2000s to increase rainfall by 15-30% each year. The materials used include potassium chloride, sodium chloride, magnesium, and others.
Without proper systems to manage weather changes, serious problems can occur. For example, in 2009, the city of Jeddah in Western Saudi Arabia was damaged by floods that killed more than 100 people, raising questions about the lack of effective drainage systems.
The U.S. National Library of Medicine states that silver iodide does not have known harmful effects on people. However, exposure to it may cause temporary yellowing of the skin for several weeks.
Storm prevention
Project Stormfury was an effort to weaken tropical cyclones by flying planes into storms and adding silver iodide to the area around the storm’s center. The United States Government conducted this project from 1962 to 1983. A similar effort using soot was tested in 1958, but the results were unclear. Scientists have suggested many ways to reduce the damage caused by hurricanes. Moshe Alamaro from the Massachusetts Institute of Technology proposed using boats with upward-pointing jet engines to create smaller storms that could interfere with larger hurricanes. Critics believe the engines might not be strong enough to make a noticeable difference.
Alexandre Chorin from the University of California, Berkeley, suggested dropping large amounts of environmentally friendly oil on the ocean’s surface to stop water droplets from forming. Experiments by Kerry Emanuel from MIT in 2002 showed that hurricane-force winds could break up the oil layer, making it ineffective. Other scientists questioned the scientific basis of this method.
A Florida company named Dyn-O-Mat, led by its CEO Peter Cordani, proposed using a patented product called Dyn-O-Gel to weaken hurricanes. The product is a powder made from a type of water-absorbing polymer that can hold up to 1,500 times its weight in water. The idea was to drop the powder into clouds to remove moisture, forcing the storm to use more energy to move heavier water droplets, which could help weaken the storm. When the gel reached the ocean, it would dissolve. Cordani partnered with Mark Daniels and Victor Miller, who owned AeroGroup, a company that operated former military planes. Using a high-altitude B-57 bomber, AeroGroup tested the substance by dropping 9,000 pounds of it into a thunderstorm near Florida’s east coast. The tests were recorded on film and shown on international news, with Doppler radar suggesting the storms were removed. However, in 2003, the program was stopped due to political pressure from NOAA. Simulations by NOAA later showed that the method would not work well for large storms like hurricanes.
Since the 19th century, some farmers have used hail cannons to try to prevent hail, but there is no clear scientific proof that these devices work. A newer idea to reduce hurricane damage involves pumping seawater into the wind near the bottom of a storm’s center and spreading it out.
Hurricane modification
NOAA created a webpage that explains different ideas about controlling tropical cyclones.
In 2007, an article titled "How to Stop a Hurricane" discussed several methods. Scientists from NOAA's Hurricane Research Division studied ways to influence hurricane behavior.
In 2017, a new idea involved using lasers similar to those used in cooling very cold materials. This method aimed to cool the top 1 millimeter of ocean water. If enough energy were used, combined with computer models, it might create a pattern that could weaken or stop a hurricane by removing heat energy.
Other suggestions for hurricane control include building large wind turbine arrays along the East Coast of the United States. These turbines could produce energy while also reducing hurricane strength before storms reach land. Scientists once considered using nuclear bombs to disrupt hurricanes, but this idea is no longer supported by the scientific community.
Another proposal involves bringing colder water from the deep ocean to the surface in front of a tropical storm. This could lower the ocean's surface temperature, possibly preventing hurricanes from growing stronger.
This method is still uncertain and difficult to carry out. Placing pumps in the path of a hurricane would be challenging, and many pumps would be needed to cool a large area of the ocean. This process would also require a lot of energy and might harm marine life.
In military
Operation Popeye was a secret mission carried out by the U.S. military from 1967 to 1972. Its goal was to extend the rainy season in Southeast Asia. Heavy rain from the operation disrupted the movement of supplies and troops for the Vietnamese army. Operation Popeye is considered the first successful use of weather-changing technology in warfare. After details about the mission were revealed, the use of weather modification in warfare was banned by the Environmental Modification Convention (ENMOD).
In an article titled "Benign Weather Modification" published in March 1997, Air Force Major Barry B. Coble briefly describes the existence of weather-changing science. He outlines how this technology has developed, especially in the hands of the Pentagon and the strongest opponents of the CIA.
In the 1990s, Air Force Chief of Staff Ronald R. Fogleman issued an order to study the ideas, abilities, and tools the United States would need to remain the leading force in the air and space in the future.
In law
In 1975, the United States and Canada made an agreement with the help of the United Nations to share information about weather modification activities.
Weather modification, especially the use of weather for harmful purposes, was discussed in the "United Nations General Assembly Resolution 31/72, TIAS 9614 Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques." This agreement was signed in Geneva on May 18, 1977. It became official on October 5, 1978. The United States officially approved it on December 13, 1979. The approval was recorded in New York on January 17, 1980.
In the United States, the National Oceanic and Atmospheric Administration (NOAA) keeps records of weather modification projects for the Secretary of Commerce. This work is done under the authority of Public Law 92-205, 15 USC § 330B, which was passed in 1971.
In 2005, the U.S. Senate proposed Bill 517, and the U.S. House of Representatives proposed Bill 2995. These bills aimed to expand weather modification experiments, create a Weather Modification Operations and Research Board, and develop a national weather modification policy. Neither bill became law.
In 2007, Senate Bill 1807 and House Bill 3445 were introduced. These identical bills proposed the creation of a Weather Mitigation Advisory and Research Board to fund weather modification research.
In 2024, Tennessee passed Bill HB 2063/SB 2691. This law bans the "intentional injection, release, or dispersion" of chemicals within Tennessee "with the express purpose of affecting temperature, weather, or the intensity of the sunlight."
The text of the bill does not directly mention the chemtrail conspiracy theory. However, the bill’s sponsor, Senator Steve Southerland, stated that the bill is intended to address this theory.
In religion and mythology
Magical and religious practices to influence the weather are found in many cultures around the world. In ancient India, people believed that sacred rituals called yajna, which included chanting prayers and making offerings, were performed by spiritual leaders to create sudden rainfall in areas that needed water. Some Indigenous American groups, as well as some European communities, practiced rituals they thought could cause rain to fall.
During the early modern era, people noticed that the loud noise from cannons and firearms used in battles sometimes led to rain falling.
In Greek mythology, a story tells of Iphigenia, who was offered as a human sacrifice to calm the anger of the goddess Artemis. Artemis had stopped the wind from moving the ships of the Achaean army at Aulis, which was the beginning of the Trojan War. In Homer’s Odyssey, Aeolus, the god who controlled the winds, gave Odysseus and his crew a bag containing all four winds as a gift. However, the sailors opened the bag while Odysseus was sleeping, looking for treasure, and the strong wind blew them off course. In ancient Rome, a sacred stone called the lapis manalis was kept outside the city in a temple of Mars. When Rome faced a drought, the stone was moved into the city. In Scotland, the Berwick witches were accused of using black magic to summon storms that sank the ship King James VI of Scotland was traveling on. In Scandinavian traditions, witches were said to sell wind in bags or trap it in wooden sticks. Sailors would buy these items and release them when there was no wind. In some towns in Navarre, people prayed to Saint Peter to bring rain during droughts. If rain did not come, the statue of Saint Peter was taken from the church and thrown into a river.
In the Hebrew Bible, it is written that the prophet Elijah told King Ahab that no rain or dew would fall until Elijah called for it. A drought lasted for 3.5 years, and when Elijah prayed, the rain returned, restoring the land. The New Testament describes Jesus calming a storm by speaking to it.
In Islam, a prayer called Salat Al-Istisqa’ is performed to ask God for rain during times of drought.
Conspiracy theories
Weather modification and climate engineering are common topics in conspiracy theories. One such theory claims that airplane contrails are changed using chemicals to affect the weather and other events. Other theories blame scientific projects, such as the High-frequency Active Auroral Research Program (HAARP).
In popular culture
In the television shows The Bionic Woman and The Six Million Dollar Man, a weather control machine created by Dr. Franklin, played by John Houseman, appeared in the "Kill Oscar" trilogy in 1976.
In Frank Herbert’s Dune series, weather control technology is used on two planets: Arrakis, where the Fremen use it to keep their population and plans to change the planet’s environment secret from the Imperium; and Chapterhouse, where the Bene Gesserit aim to transform the planet into a desert.
Many superhero stories include characters who can control the weather. One example is Storm, a character from Marvel Comics.
In the children’s book Cloudy with a Chance of Meatballs, the fictional town of Chewandswallow has weather that rains food instead of rain or snow. This becomes so extreme that the town’s people must move to another location. The story was adapted into a movie, where Flint Lockwood, a scientist and outcast from the town, invents a machine that turns water from clouds into food.
In the Star Trek franchise, the United Federation of Planets uses weather control technology and has the ability to change planets’ environments.