In this edition of Doom Tech, we are exploring the chemtrails conspiracy theory. Believers claim that airplanes have been used for decades to secretly spray dangerous chemicals on people.
These conspiracy theorists cite as proof vapour clouds made by jets. They say that these chemtrails - short for chemical trails - last longer than normal vapour trails made by planes do.
Subscribers to this conspiracy theory blame governments, and shadowy corporations for these projects. Conspiracy theorists claim that the objectives of spraying chemicals from planes are wide-ranging.
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These include causing widespread illnesses so that pharma companies can reap profits, sterilisation for population control, and testing of chemical and biological weapons. Other alleged objectives include damaging crops to manipulate stock markets, and even modifying the weather.
The ongoing heatwave in the United Kingdom has handed ammo to chemtrail believers. Claims recently emerged on social that the heatwave was engineered to "restrict public rights and freedoms in the future" in the name of climate change.
The origins of the chemtrails conspiracy theory are rooted in some fact, as most conspiracy theories are. One of the inspirations for the theory is the secret germ warfare tests conducted in the 1950s and 1960s by the UK in which many areas were sprayed with airborne chemicals. 1950 also saw San Francisco in the US being sprayed with chemical agents to see the effects of a possible bioweapon attack.
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Another source of the chemtrails theory is the US Air Force's 1996 paper in which weather modification is suggested as a future weapon. Another fact cited by conspiracy theorists in a 1991 patent application on injecting particles into the Earth's upper atmosphere to reflect some sunlight to reduce global warming.
The theory has received another boost in recent times with the discovery of a new class of chemical compounds in the atmosphere. When scientists detected hydrotrioxides and said that they might possibly lead to respiratory and cardiovascular diseases, conspiracy theorists had another weapon.
Reacting to the fresh surge in conspiracy claims, scientists have said the research so far has not highlighted any link to airplane discharges.
Chemtrail believers also share old videos as proof of the conspiracy. Fact-checkers claim that such videos are old recordings of military planes creating "smoke screens" to hide ships from enemies.
Chemtrail claimers also share photos of pilots wearing badges exposing the disastrous project. fullfact.org says that these are part of a running joke among pilots making fun of the conspiracy theory.
The chemtrails conspiracy theory is unlikely to be correct due to a host of reasons. First, scientists say that the alleged chemicals cannot reach the ground from high altitudes.
Second, a conspiracy at such a large scale would involve thousands of people. If it has been carried out for decades, at least a few whistle-blowers would've emerged to expose a project which is hurting their own friends and families.
But all this still doesn't explain what exactly those thin clouds left behind by airplanes are. Experts say that the clouds are contrails, which is short for condensation trails. They are created by water vapour and exhaust fumes from plane engines.
This vapour is emitted at high altitudes at freezing temperatures, and freezes into ice crystals. If air humidity is low, the ice crystals dissipate quickly. But in areas with high humidity, the ice crystals persist, creating visible trails.
This does not mean that airplanes never spray chemicals from the air. Aircraft are routinely used to sprinkle pesticides and herbicides on fields. They also scatter chemicals to disperse oil spills. Chemicals to kill mosquitos and other bugs, and fire retardants to fight blazes are also sprayed from planes.
However, all is not alright. Experts say that chemtrails might be fake, but that doesn't mean that contrails are harmless.
There are growing concerns that high-altitude jets are contributing to climate change. Plane contrails may be hurting the environment through radiative forcing which refers to solar energy Earth absorbs versus what it radiates back to space. Some groups are pushing for more research on contrails' environmental effects.
In a bid to destroy conspiracy theories, authorities must not brush genuine concerns under the carpet.