Hot topic: should I worry about chemtrails?

Is there a worldwide government conspiracy to poison us all by spraying chemicals out of the 15,000 aircraft crisscrossing the globe at any given moment? No, almost certainly not.

Ever since the US Air Force published a paper about the hypothetical harnessing of weather for military objectives — 'truthers' have shared 'evidence' of a shadowy global aviation conspiracy.

Photograph by Getty Images
By James Draven
Published 8 Apr 2019, 23:58 BST, Updated 13 Sept 2021, 17:17 BST

My father's ears prick up and he dashes from the lounge into the garden, casting his eyes heavenward. I'm seven years old and I follow him, assuming I'm about to witness the Four Horsemen of the Apocalypse dive bombing our house. Instead, I'm disappointed to see an airliner flying overhead, leaving a white trail across the sky.

My dad is something of an aviation enthusiast and this compulsive aircraft-spotting was a regular occurrence throughout my childhood. I asked my father what these white lines that hung in the air long after the plane had vanished from sight were, and he told me they were contrails: condensation trails. They're formed when humid jet exhaust condenses into ice crystals in the cold, dry, high-altitude air. This was back in 1987. I was satisfied with that explanation then, and I am now.

Not everybody is so easily placated, though, and over the past couple of decades — ever since the US Air Force published a paper in 1996 about the hypothetical harnessing of weather for military objectives — 'truthers' in their thousands have taken to YouTube, forums, talk radio and hundreds of websites to share 'evidence' for a shadowy global aviation conspiracy.

Some people believe that, since the mid-1990s, the government (usually the US government, colluding with others around the world) has been using aircraft to secretly spray the globe with chemical agents, with a range of supposed purposes including weather modification; mind control; chemical/biological weapons testing; stock price manipulation by damaging crops; and even causing illnesses for massive pharmaceutical companies to exploit.

It's often claimed that these 'chemtrails' are distinguished from normal contrails because they remain in the sky for longer than they did prior to the mid-90s, and dissipate into cirrus clouds.

It's a load of codswallop, but in this age of 'fake news', the conspiracy theory seems to have moved beyond American far-right circles and gone mainstream. Back in 2011, a survey of the US, Canada, and UK showed that an incredible 16.6% of respondents believed in chemtrails. More recent data exists for our American cousins: a 2016 a poll found that 30-40% of the US population subscribed to the theory.

With government agencies swamped by complaints, the US Environmental Protection Agency (EPA) re-released the Hazardous Waste Report in 2015 in conjunction with NASA, the National Oceanic and Atmospheric Administration (NOAA), and the Federal Aviation Administration (FAA), to reassure the public.

Following this, in an August 2016 peer-reviewed study by the Carnegie Institution for Science, 76 out of 77 leading atmospheric scientists said they could find no evidence whatsoever to support the theory of a government chemtrail programme.

This clearly did little to convince hardcore believers; in 2017, solar geo-engineers at Harvard reported to VICE News they were receiving death threats and hate mail accusing them of being in on the conspiracy.

So, with such scientific proof to the contrary, why do these theories persist? If the government refutes them and scientists disprove them, then why are some people so adamant we're being lied to?

No amount of evidence will dissuade a die-hard conspiracy theorist, because any evidence to the contrary is inevitably dismissed as part of a massive cover up. Hey, maybe my dad is part of it as well.

So, contrails are nothing to worry about, right?

While the EPA report concludes, 'contrails pose no direct threat to public health,' it does add: 'Contrail cloudiness might contribute to climate change. Climate change may impact on public health and environmental protection.'

Have you seen a picture of a plane cabin with the seats replaced with chemical tanks?

What you've seen is an image of a plane filled with water tanks. These flight test ballast barrels are there to simulate passenger weight, and are interconnected so the water can be pumped to different parts of the cabin allowing engineers to assess the planes' performance under a variety of load conditions and different centres of gravity.

Published in the March 2018 issue of National Geographic Traveller (UK)

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