Long-lasting contrails aren’t proof of chemtrails, and they aren’t caused by aluminum, barium, or other metals

As Science Feedback has covered on multiple prior occasions, there is no evidence that chemtrails exist. But a Facebook Reel posted on 14 February, and since viewed more than 500,000 times, asserts that chemtrails do exist – specifically claiming that they’re longer-lasting than contrails; that they’re made of gas containing aluminum, barium, and other metals; and citing a particular U.S. patent as evidence.

These claims are inaccurate. The long-lasting trails that the Reel describes as “chemtrails” are just contrails; scientists know that contrails can last for several hours. Aluminum and barium are proposed methods of cooling the atmosphere, but the post exaggerates and misrepresents them. The cited patent has no connection to weather modification – in any event, citing a patent isn’t proof that an idea is in use. 

We’ll explore all of these below.

No evidence that chemtrails exist

There is no evidence that chemtrails exist. The Reel’s images of supposed chemtrails are, indeed, simply contrails.

Meteorologists know well how contrails form, as described by the UK’s Met Office. Contrails form because jet engine exhaust contains water vapor – not metals like aluminum or barium, as the claim suggests. If a plane flies at altitudes above around 6,000 meters (20,000 feet), the air is cold enough that this water vapor rapidly condensates and freezes into ice crystals, leaving visible trails in the sky.

Eventually, the ice crystals sublimate back into water vapor, and the trails fade away – how long this takes depends on the moisture in the surrounding air, with contrails lasting longer in more humid air. The video claims that “contrails” dissipate after “several minutes”, while “chemtrails” last longer. But scientists, who can watch contrails thanks to Earth-observing satellites, are well aware that contrails can last much longer than “several minutes”. A 2017 study of contrails, for example, estimated that the average contrail visible to satellites lasted 3.7 hours. According to NASA, satellites have observed contrails lasting as long as 14 hours. 

Many scientists do not work for institutions like governments that would have the resources to conduct a large-scale program of spraying chemicals into the atmosphere. If chemtrails did exist, such scientists would almost certainly have found some evidence of them. But when a different 2017 study surveyed 77 scientists on the matter, 76 of them said they had never found any such evidence^[1].

Patent US3813875A is not evidence of weather control

The patent cited in the video – U.S. Patent 3813875A – was awarded to NASA in 1974. This patent does not describe a means of weather control. Rather, it describes a method of launching a rocket that releases barium in the upper atmosphere, which allows scientists on the ground to study how the barium interacts with the solar wind.

Experiments like those described in the patent had been conducted as early as the 1960s and are still conducted in the 21st century. Crucially, these experiments occur in the upper atmosphere – the NASA patent doesn’t list an altitude, but a 2014 experiment released barium ions at altitudes of 150-400 kilometers (90-250 miles). That’s many times higher than the maximum altitude of most aircraft; it’s also well above the troposphere, the atmosphere’s lowest layer (topping out at 6-20 kilometers or 4-12 miles high), where most weather occurs. 

Recently, we’ve seen many claims cite patents as proof that weather is being manipulated – the claim in this review is one of them. But even a patent that did have any relevance to weather modification – as many patents do – is not evidence of chemtrails. A patent does not prove that its invention has ever been used or even that it has scientific merit.

This is because a patent is a legal document, not a scientific or technical one. Patents are usually written by lawyers, not scientists or engineers. Patent examiners are more interested in whether an invention does something new than whether it’s scientifically valuable. Patent applications might provide technical background on how their invention works, but they don’t usually provide a methodology or detailed results, and they aren’t peer-reviewed by others in the scientific community – all of which are crucial for scientific work to be accepted.

A patent gives its holder the rights to the patented invention; simply because someone has the rights to an invention does not mean that they or anyone else has ever actually used it. It’s hard to gauge how many patents actually get used, but today, observers estimate that anywhere from 40 to 90 percent of patents are never commercialized.

The claim misrepresents how cloud seeding, aluminum, and barium may actually be used in the atmosphere

The Reel’s claim may derive some of its details from potential methods of actually modifying the weather or Earth’s climate: in particular, cloud seeding and stratospheric aerosol injection. These should not be taken for chemtrails.

‘Creating rain’ is one goal of cloud seeding, a technique that aims to control precipitation. But cloud seeding does not work by ‘blocking the sun’ or filling the sky with trails of ‘chemical gas’ – instead, cloud seeding usually works (as we describe in this past review) by releasing particles of a substance like silver iodide or dry ice into the air. In theory, this encourages water droplets to form around the particles.

Cloud seeding is not a secret; public, well-documented cloud seeding programs have been around for several decades. China, India, Mexico, Thailand, the UAE, the U.S., and other countries all actively carry out cloud seeding efforts today. At the same time, there is no scientific consensus on whether cloud seeding is effective at all. The data we have suggests that, at best, cloud seeding can make rainstorms larger in certain conditions and on a local scale^[2-5].

The idea of ‘blocking the sun’ may reflect a different, proposed method of counteracting global warming known as stratospheric aerosol injection. This method would cool the planet by releasing a substance into the atmosphere that increases the amount of sunlight reflected back into space. The most commonly proposed substance is sulfur dioxide, but others do include aluminum and barium: aluminum in the form of aluminum oxide, a compound that’s actually very common in the Earth’s crust, including in gemstones like ruby and sapphire; and barium in the form of barium titanate, a material used in some electronics^[6].

Nevertheless, it must be stressed that stratospheric aerosol injection is a proposed method. The very idea of modifying the climate is controversial, and even small-scale tests have been cancelled after facing opposition from the public and from scientists^[7]. As of now, there has never been a large-scale test of the method, and it is certainly not being launched from commercial flights.

Conclusion

There is no evidence that chemtrails exist, and the post’s details are inaccurate. Contrails don’t always dissipate immediately, and they can last for multiple hours in humid air; this doesn’t make them chemtrails. The cited patent has nothing to do with modifying the weather, and even if it did, a patent is not proof of use. Some parts of the post – such as ‘creating rain’ and the use of aluminum and barium – are aspects of other proposed weather modification methods, but these have no relation to chemtrails.

References:

1. Shearer et al. (2016) Quantifying expert consensus against the existence of a secret, large-scale atmospheric spraying program. Environmental Research Letters.
2. Al Hosari et al. (2021) The UAE Cloud Seeding Program: A Statistical and Physical Evaluation. Atmosphere.
3. Wang et al. (2019) The Extra-Area Effect in 71 Cloud Seeding Operations during Winters of 2008–14 over Jiangxi Province, East China. Journal of Meteorological Research.
4. Zheng et al. (2021) Evaluation of the First Negative Ion-Based Cloud Seeding and Rain Enhancement Trial in China. Water.
5. Rasmussen et al. (2018) Evaluation of the Wyoming Weather Modification Pilot Project (WWMPP) Using Two Approaches: Traditional Statistics and Ensemble Modeling. Journal of Applied Meteorology and Climatology. 
6. Effiong and Neitzel. (2016) Assessing the direct occupational and public health impacts of solar radiation management with stratospheric aerosols. Environmental Health.
7. Bednarz et al. (2023) Injection strategy – a driver of atmospheric circulation and ozone response to stratospheric aerosol geoengineering. Atmospheric Chemistry and Physics.