Chemtrail conspiracy theory

An Airbus A340's engines leaving a water condensation trail (contrail) – miniature clouds formed by the engine exhaust

The chemtrail conspiracy theory /ˈkɛmtreɪl/ is the erroneous^[1] belief that long-lasting condensation trails left in the sky by high-flying aircraft are actually "chemtrails" consisting of chemical or biological agents, sprayed for nefarious purposes undisclosed to the general public.^[2] Believers in this conspiracy theory say that while normal contrails dissipate relatively quickly, contrails that linger must contain additional substances.^[3]^[4] Those who subscribe to the theory speculate that the purpose of the chemical release may be solar radiation management,^[3] weather modification, psychological manipulation, human population control, biological or chemical warfare, or testing of biological or chemical agents on a population, and that the trails are causing respiratory illnesses and other health problems.^[2]^[5]

The claim has been dismissed by the scientific community.^[6] There is no evidence that purported chemtrails differ from normal water-based contrails routinely left by high-flying aircraft under certain atmospheric conditions.^[7] Proponents have tried to prove that chemical spraying occurs, but their analyses have been flawed or based on misconceptions.^[8]^[9] Because of the conspiracy theory's persistence and questions about government involvement, scientists and government agencies around the world have repeatedly explained that the supposed chemtrails are in fact normal contrails.^[3]^[10]^[11]

The term chemtrail is a portmanteau of the words chemical and trail, just as contrail blends condensation and trail.^[12]

^ Science, Carnegie (12 August 2016). ""Chemtrails" not real, say leading atmospheric science experts". Carnegie Institution for Science. Archived from the original on 20 December 2016. Retrieved 11 May 2019. Some groups and individuals erroneously believe that the long-lasting condensation trails, or contrails, left behind aircraft are evidence of a secret large-scale spraying program. They call these imagined features "chemtrails".
^ ^a ^b Cite error: The named reference currsci was invoked but never defined (see the help page).
^ ^a ^b ^c Cite error: The named reference USAtoday2001 was invoked but never defined (see the help page).
^ Cite error: The named reference knight was invoked but never defined (see the help page).
^ Cite error: The named reference weatherwise was invoked but never defined (see the help page).
^ Cite error: The named reference Quantifying expert consensus was invoked but never defined (see the help page).
^ Cite error: The named reference air force was invoked but never defined (see the help page).
^ Cite error: The named reference barium was invoked but never defined (see the help page).
^ Cite error: The named reference Kreidler 2008 was invoked but never defined (see the help page).
^ Cama, Timothy (13 March 2015). "EPA confronts 'chemtrails' conspiracy talk". The Hill. Retrieved 10 December 2016. Conspiracy theorists say that government officials or others are using jets to spray harmful chemicals into the atmosphere. They cite the contrails left by jets as evidence of the chemicals. The EPA has added a new notice to its website, which links to a fact sheet explaining that the trails left by jets in the atmosphere are only ice particles and contain no harmful chemicals. "Contrails are line-shaped clouds or 'Condensation trails' composed of ice particles that are visible behind jet aircraft engines under certain atmospheric conditions and at times can persist", says the notice, posted to the EPA's website Friday. "EPA is not aware of any deliberate actions to release chemical or biological agents into the atmosphere". Theorists have posited that the chemicals are meant to control the climate, harm humans, or kill them. The fact sheet from the EPA and other federal agencies like the Federal Aviation Administration and the National Oceanic and Atmospheric Administration was first published in 2000 when the chemtrails conspiracy became popular on the Web. An EPA spokeswoman said the agency frequently receives questions about chemtrails.
^ Smith, Oliver (24 September 2013). "'Chemtrails' and other aviation conspiracy theories". The Telegraph. Archived from the original on 11 January 2022. Retrieved 11 December 2016. So persistent is the chemtrail theory that US government agencies regularly receive calls from irate citizens demanding an explanation...The conspiracy theory took root in the Nineties, with the publication of a US Air Force research paper about weather modification...Governments and scientific institutions have of course dismissed the theories, and claim those vapor trails which persist for longer than usual or disperse to cover a wide area, are just normal contrails.
^ "chemtrail". Oxford English Dictionary (Third ed.). Oxford University Press. December 2011.(subscription required)

[1] Science, Carnegie (12 August 2016). ""Chemtrails" not real, say leading atmospheric science experts". Carnegie Institution for Science. Archived from the original on 20 December 2016. Retrieved 11 May 2019. Some groups and individuals erroneously believe that the long-lasting condensation trails, or contrails, left behind aircraft are evidence of a secret large-scale spraying program. They call these imagined features "chemtrails".

[currsci-2] Cite error: The named reference currsci was invoked but never defined (see the help page).

[USAtoday2001-3] Cite error: The named reference USAtoday2001 was invoked but never defined (see the help page).

[knight-4] Cite error: The named reference knight was invoked but never defined (see the help page).

[weatherwise-5] Cite error: The named reference weatherwise was invoked but never defined (see the help page).

[Quantifying_expert_consensus-6] Cite error: The named reference Quantifying expert consensus was invoked but never defined (see the help page).

[air_force-7] Cite error: The named reference air force was invoked but never defined (see the help page).

[barium-8] Cite error: The named reference barium was invoked but never defined (see the help page).

[Kreidler_2008-9] Cite error: The named reference Kreidler 2008 was invoked but never defined (see the help page).

[TheHill2015-10] Cama, Timothy (13 March 2015). "EPA confronts 'chemtrails' conspiracy talk". The Hill. Retrieved 10 December 2016. Conspiracy theorists say that government officials or others are using jets to spray harmful chemicals into the atmosphere. They cite the contrails left by jets as evidence of the chemicals. The EPA has added a new notice to its website, which links to a fact sheet explaining that the trails left by jets in the atmosphere are only ice particles and contain no harmful chemicals. "Contrails are line-shaped clouds or 'Condensation trails' composed of ice particles that are visible behind jet aircraft engines under certain atmospheric conditions and at times can persist", says the notice, posted to the EPA's website Friday. "EPA is not aware of any deliberate actions to release chemical or biological agents into the atmosphere". Theorists have posited that the chemicals are meant to control the climate, harm humans, or kill them. The fact sheet from the EPA and other federal agencies like the Federal Aviation Administration and the National Oceanic and Atmospheric Administration was first published in 2000 when the chemtrails conspiracy became popular on the Web. An EPA spokeswoman said the agency frequently receives questions about chemtrails.

[Telegraph2013-11] Smith, Oliver (24 September 2013). "'Chemtrails' and other aviation conspiracy theories". The Telegraph. Archived from the original on 11 January 2022. Retrieved 11 December 2016. So persistent is the chemtrail theory that US government agencies regularly receive calls from irate citizens demanding an explanation...The conspiracy theory took root in the Nineties, with the publication of a US Air Force research paper about weather modification...Governments and scientific institutions have of course dismissed the theories, and claim those vapor trails which persist for longer than usual or disperse to cover a wide area, are just normal contrails.

[oed-12] "chemtrail". Oxford English Dictionary (Third ed.). Oxford University Press. December 2011.(subscription required)

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