Chemtrails
Chemtrails refer to the condensation trails, or contrails, left behind by airplanes as they fly through the atmosphere. The term combines "chemical" and "contrail" and is primarily associated with a conspiracy theory suggesting that these trails contain harmful chemicals released by the government for sinister purposes. Proponents of this theory argue that while normal contrails dissipate quickly, chemtrails persist and spread, potentially affecting weather patterns, human health, and even population control.
Despite the widespread belief in chemtrails, atmospheric scientists have thoroughly debunked the theory, explaining that contrails are a natural byproduct of hot exhaust meeting cold air at high altitudes. The characteristics of contrails can vary based on environmental conditions, such as humidity and temperature, leading to misconceptions about their appearance and behavior. While the conspiracy theory gained traction in the late 1990s, particularly in the United States, it has been met with skepticism from scientific communities who highlight a lack of evidence supporting the claims.
The discourse around chemtrails continues, reflecting broader societal tendencies to question governmental actions and seek alternative explanations for environmental phenomena. While some individuals maintain their belief in chemtrails, the scientific consensus remains that they are simply water vapor trails, with no malicious intent or harmful substances involved.
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Chemtrails
Chemtrails are the condensation trails, or contrails, left by airplanes in the sky. The word chemtrail is a combination of the words chemical and contrail. Some conspiracy theorists believe chemtrails contain chemicals that the US government clandestinely releases into the environment for menacing purposes. The conspiracy theory of chemtrails holds that ordinary airplane contrails dissipate into the atmosphere quickly, while chemtrails linger in the sky and spread outward to form clouds. Theorists believe the chemicals contained in these clouds are intended to influence the weather, sterilize people to reduce the human population, or control people's minds.
Atmospheric scientists have comprehensively rejected the chemtrails conspiracy theory since it first arose in the United States in the late 1990s. They assert that airplanes create contrails as a natural result of the hot exhaust from their engines meeting the cold air at high altitudes. This creates visible water vapor in the air, similar to the clouds of vapor people's breath creates in cold environments. Conspiracy theorists maintain that ordinary plane contrails appear differently from chemtrails.
Background
Contrails, the lines of white water vapor that most planes emit as they fly, result from the normal interaction of substances at different temperatures in the atmosphere. Plane engines release hot, humid exhaust as they fly. The air at a plane's cruising altitude is much colder than air closer to the ground. The water vapor contained in the exhaust condenses in the cold air and creates a cloud of minuscule water droplets and ice particles. As planes travel, the clouds created by their exhaust leave behind the long, white trails known as contrails.
The physical nature of the contrails may vary based on atmospheric conditions. Contrails produced in dry air tend to be thin and dissipate quickly. Meanwhile, contrails in humid air are thicker and take longer to disappear into the air. Contrails of any thickness and density may appear to be spinning as vortices in the air. This is usually due to the plane's wings having spun the air as they passed. The contrails are then caught in these vortices.
This scientific information is widely available to the global public. However, it was around 1996 when Americans first came to suspect contrails of being more than they appeared. That year, the US Air Force published a report called "Weather as a Force Multiplier: Owning the Weather in 2025." The report suggested that the US military could hypothetically develop the necessary technology to control weather by the year 2025.
Into the late 1990s, theories about exactly how the US government would control the weather began to abound on the internet. Theorists recounted personal experiences of how they had seen plants die and people become ill after planes had flown over them, leaving contrails in their wakes.
The online theories progressed over time and ultimately developed into the idea of chemtrails, airplane contrails containing government-issued chemicals designed for a variety of purposes. These alleged purposes ranged from the relatively benign, such as trying to slow the pace of global warming, to the nefarious, such as mind control and population control through sterilization and slow-working poison that caused respiratory illnesses. While the conspiracy theory originated in the United States, belief in chemtrails has since spread around the world.
Overview
Despite insistence by the Air Force that the US government was not using chemicals in airplane contrails to influence the weather or the American people, conspiracy theorists adhered to the idea of chemtrails. They established numerous websites for theorists to share their views and photos of purported chemtrails. According to the academic paper "Solar Geoengineering and the Chemtrails Conspiracy on Social Media," published in 2017 by Palgrave Communications, in 2013, the American think tank Public Policy Polling claimed that 5 percent of Americans believed in chemtrails. In 2024, Statista Research estimated the percentage to be much higher depending on the specific theory. For example, it estimated that about 23 percent of Americans supported the belief that 9/11 was an inside job, while others believed that chemtrails were used to control the population. According to Statista, one in five Americans believed that climate change was a hoax.
For nearly the entirety of the existence of the chemtrails conspiracy theory, scientists and others have attempted to refute the idea that the US government is attempting to control any aspect of American life with plane-deployed chemicals. Nonprofessional arguments against the chemtrails theory primarily question why the government would poison its people for any reason, and, secondly, why it would choose to do this by spraying chemicals tens of thousands of feet in the air, hoping the agents would reach people on the ground before wind could blow them away.
Meanwhile, atmospheric scientists dispute conspiracy theorists' claims that chemtrails in the sky appear different from normal contrails. The scientists claim contrails are different shapes and sizes and last longer or shorter than others because of their altitude and atmospheric conditions such as humidity, temperature, and vapor pressure. The water vapor produced naturally by the combustion of jet fuel enters the cold atmosphere and, if humidity is high, forms thick trails of clouds that remain in the sky for long periods. Wind created by the airplanes can then spread these contrails for miles, giving them the appearance of natural clouds in the sky.
Additionally, some areas of the sky contain more contrails than others on a given day because airplanes tend to fly the same flight paths through every region of the country. Contrails formed at different altitudes and in different humidity levels may be thinner and disappear more quickly.
Still other arguments attempt to refute the chemtrails concept with logic and philosophy. In the 2010s, Harvard University climate science organization the Keith Group argued that grand claims require grand explanations, and that there is no evidence for the existence of chemtrails. The group said that for chemtrails to be plausible, the US government would have to maintain facilities for the manufacture and distribution of the alleged chemicals in the contrails. The scope of such an undertaking would be so great that thousands of people would be required to work on it constantly. This would increase the likelihood that at least one of these people would reveal the chemtrails plot to the American public on moral grounds, according to the Keith Group.
Even contrails that appear definitively unusual to observers can be explained. Planes flying normally in the distance can appear to viewers as flying almost vertically, toward the sky. This is due simply to the viewer's perspective and the curvature of Earth. Some military planes leave no contrails at all because they are designed to fly stealthily at altitudes where no contrails will be created.
Climate scientists admit that the only threat airplane contrails may pose to the public worldwide is in their contribution to global warming when they spread out into wide clouds.
Bibliography
"Chemtrails Conspiracy Theory." Keith Group, Harvard University, keith.seas.harvard.edu/chemtrails-conspiracy-theory. Accessed 7 Nov. 2017.
"Conspiracy Theorieswww.statista.com/topics/5103/beliefs-and-superstition-in-the-us/#topicOverview. Accessed 18 Nov. 2024.
Daley, Jason. "Science Officially Debunks Chemtrails, but the Conspiracy Will Likely Live On." Smithsonian, 22 Aug. 2016, www.smithsonianmag.com/smart-news/science-officially-debunks-chemtrails-conspiracy-live-180960139/. Accessed 7 Nov. 2017.
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Herreria, Carla. "Here's What Scientists Really Think about 'Chemtrails.'" Huffington Post, 18 Aug. 2016, www.huffingtonpost.com/entry/scientists-address-chemtrail-theory‗us‗57b3a14ee4b0edfa80da2ffc. Accessed 7 Nov. 2017.
McGrath, Jane. "What Are Chemtrails, and Should You Be Scared of Them?" HowStuffWorks.com, 7 Mar. 2011, science.howstuffworks.com/transport/flight/modern/what-are-chemtrails1.htm. Accessed 7 Nov. 2017.
Rossmann, Jenn Stroud. "Why Do Jets Leave a White Trail in the Sky?" Scientific American, www.scientificamerican.com/article/why-do-jets-leave-a-white/#. Accessed 7 Nov. 2017.
Smith, Oliver. "Incredible Contrail Made by Boeing 787—What Causes Them, and Are They Part of a Global Conspiracy?" Telegraph, 4 July 2017, www.telegraph.co.uk/travel/news/chemtrails-contrails-and-other-aviation-conspiracy-theories/. Accessed 7 Nov. 2017.
Tingley, Dustin, and Gernot Wagner. "Solar Geoengineering and the Chemtrails Conspiracy on Social Media." Palgrave Communications, 31 Oct. 2017, www.nature.com/articles/s41599-017-0014-3. Accessed 7 Nov. 2017.