We’ve all seen the white lines drifting behind jets, streaking across the blue sky.
The lines are called contrails, short for condensation trails, and they appear when water vapor condenses and freezes around a plane’s exhaust, according to the University Corporation for Atmospheric Research.
At least that’s what science says. In recent years, an increasing number of people believe that these traces are actually chemical traces; a well-established conspiracy theory that suggests these traces are not caused by condensation at all, but rather chemicals sprayed by the government.
Although the theory may seem far-fetched to some, chemtrails have become a widespread conspiracy both in the United States and around the world, despite evidence to the contrary.
What is the Chemtrails conspiracy theory?
The idea of chemtrails has been around since 1996, with roots largely in an Air Force research paper published that same year: “Weather as a Force Multiplier: Owning Weather in 2025.” The Environmental Protection Agency stated that this document outlines a “future weather modification system to achieve military objectives” using “aerospace forces” and “does not reflect current military policy, practice, or capability.”
At its most basic, the chemtrails conspiracy theory suggests that smoke trails are not created by water vapor, but are instead a sign that the government, the rich, or a combination of the two are releasing toxic chemicals into the air and creating those chemicals. White lines.
Opinions vary as to the purpose of these so-called toxic chemicals. Some believe the chemicals are being used to poison humanity, others say it’s for mind control, and some think it’s a way for the government to control the weather.
There is no single official version of the theory, said Sijia Xiao, a doctoral candidate at the University of California, Berkeley, who conducted a 2021 study investigating the chemtrails conspiracy theory and interviewing 20 believers and ex-believers. Instead, individuals “pick and choose aspects that suit them, mixing their personal interpretations or selectively adopting parts of the theory.”
How did the Chemtrails conspiracy theory come about?
The idea that the government is spraying chemicals on humanity is not entirely unfounded.
During the Cold War, the British government staged more than 750 fake chemical warfare attacks on the public, according to researchers. This exposed hundreds of thousands of people to zinc cadmium sulfide, a chemical chosen because of its small size (similar to that of microbes) and the fact that it glows under ultraviolet light, making it easy to track. At the time, the chemical was thought to be nontoxic, but repeated exposure could cause cancer.. The US did the same in the 1950s and 1960s; used the chemical as a tracer to test the distribution of biological weapons.
Although these tests were conducted decades ago, the theory has evolved so much that in 2016, the EPA released a 14-page document describing contraceptives, outlining the chemicals used by the Air Force, and attempting to dispute the conspiracy.
In 2021, a Facebook post claiming that President Joe Biden “manipulated” the weather through chemtrails and caused Texas to deep freeze for a week that February went viral, with hundreds of people engaging with the message.
Thousands of people on X follow accounts dedicated to tracking these chemical signatures and publishing their evidence. A 2017 study of a nationally representative sample of 1,000 people found that about 10% of Americans “completely” believed in the conspiracy, while more than 30% of Americans found it to be at least “somewhat” true.
Belief in conspiracies is often based on skepticism from authority figures, and social media also plays a role in exaggerating the problem, Xiao said.
The algorithmic nature of social media means people see information that reinforces their existing beliefs. Coye Cheshire, a professor of social psychology at UC Berkeley who participated in the study with Xiao, said the ex-believers interviewed attributed their continued belief in part to the “abundance of conspiratorial information” in social media posts. Scientific evidence disproving the theories will not appear in their publications or social groups. Even so, other believers will only strengthen the theory.
Cheshire said the malleable nature of the conspiracy theory gives it power.
“The power of the conspiracy, as some believers tell us, is that it can be adjusted to fit any new information because seemingly ‘absolutely unprovable’ evidence never comes to light,” Cheshire said. “For example, even if believers are unsure that so-called chemical tracers are actually being used for population control, the narrative can easily shift to weather manipulation and climate change without requiring any new information or evidence.”
There is also the simple fact that we can see the contrails with our own eyes. Xiao added that their visibility and presence in daily life has helped attract more attention to the theory.
“The chemtrails were the most interesting conspiracy, because it is right in front of our eyes and we still choose to ignore it,” one believer told Xiao and Cheshire.
Although the theory may seem absurd to some, believers’ main concerns stem from “legitimate social and environmental issues that require attention,” Xiao said. Distrust of government, concerns about environmental problems, and even the fight against chronic disease may lend credibility to the chemtrails theory and suggest that something else is causing these societal problems.
Are Chemtrails real? Here’s what the experts say
Scientists said there was no evidence of the presence of chemical traces. Harvard researchers noted that even if there was a government conspiracy in airliner contrails, such a large-scale program would be difficult to cover up, given the amount of people that would be required for the operation.
Scientists around the world have conducted studies debunking the chemtrail conspiracy theory, explaining at length the existence and variance of contrails. Even Edward Snowden, the whistleblower who leaked classified information from the National Security Agency, He stated that chemtrails “aren’t a thing.”
Still, believers remain unconvinced. Belief in the theory has become so strong that meteorologists around the world report an increase in harassment and threats, often after extreme weather, especially from conspiracy theorists who accuse them of withholding information.
“Collective bargaining within these communities often suppresses rational dissent from scientists,” Xiao said. This “makes it extremely difficult for factual corrections to change these deep-rooted beliefs.”
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