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‘Chemtrails’ are a con, say experts

Conspiracy theory: aeroplanes up to no good high above Horfield Common in Bristol

Vast conspiracy: contrails over Horfield Common in Bristol.

By Hamish Johnston

Is there a government-led conspiracy that uses aeroplanes to lace the atmosphere with chemicals? Of course there isn’t, and now there is a peer-reviewed study that says so.

Dubbed the “secret large-scale atmospheric programme” (SLAP), the conspiracy concerns condensation trails (contrails) that can often be seen high up in the sky. These are the lines of cloud that are formed when water condensates around particulate matter in the exhaust from jet engines. But are those contrails actually “chemtrails” that are spreading noxious substances far and wide?

Well, that’s exactly what a disappointingly high percentage of people in the US, UK and Canada believe. Indeed, 17% of 3015 people who were questioned about contrails in 2011 said it was true or partly true that there is a secret government programme that uses aeroplanes to put harmful chemicals into the air.

If you want to learn more, type “chemtrails” into a search engine and prepare to be amazed at claims that contrails are related to the testing of biological weapons, a geoenginering effort to mitigate global warming or even a population-control programme.

Now, the first scientific and peer-reviewed study of chemtrail claims has been published in Environmental Research Letters (conspiracy theorists will no doubt point out that this journal is published by the same publisher that brings you Not surprisingly, the study finds little evidence that chemtrails exist, as Liz Kalaugher explains in a news article on environmentalresearchweb: “Are chemtrails a con?“.

Sadly, I don’t think this will convince many chemtrail enthusiasts.

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  1. Richard Shorter

    This is a subject for psychologists, not physicists. Some people are biased towards believing in a conspiracy theory about just about anything that they do not understand or that they are suspicious about.
    There will be more contrails around “than there used to be” because the number of planes in the sky continually increases. As the latest engines have increased bypass ratios then those contrails are likely to remain visible for longer.

  2. John Watt

    Is this the same element of psychology that has so many people believing in AGW? Passionately presented arguments in a “fact-free” environment do result in misconceptions. Just tells us to make the effort to uncover the facts and then present them in a manner we can all understand.

  3. There is no secret government programme using aeroplanes to put harmful chemicals into the air – they’re doing it all on their own without any government help whatsoever.

  4. msafwan

    People isn’t expert at differentiating between facts & opinions. One day they looked up and wonder at contrails, then the next day they read about SLAP and made a grave mistake in assuming that logics (or deductions) is fact.


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