CLAIMS THAT TRAILS of condensation left in the sky after airplanes pass show that the government is intentionally modifying the climate are baseless.

The then-Minister of State at the Department of the Environment, Climate and Communications Jack Chambers was questioned about it in the Seanad last week, where he confirmed that Met Éireann has not conducted such weather modification, nor do they know of any such tests in Irish airspace.

“This is Not a Conspiracy Theory any more,” one former National Party local candidate wrote on Facebook next to photos of streaky clouds in the sky. “It is without a doubt that the Irish Aviation Authority is approving this. It is obviously trying to blot out the Sun.”

“These white stripes are not natural clouds,” another Irish social media user wrote. “This is solar geoengineering,”

One Instagram account with more than 7,500 followers features more than 1,860 posts, almost all of which consist of conspiracy theories about condensation trails, including claims that the government is trying to modify the weather, but also iterations of the “chemtrail” conspiracy theory, which states that secretive powers are spraying people with nefarious substances through commercial airplane trails.

Many versions of this theory have been debunked, though new iterations appear frequently.

The original theories were spread in the United States in the 1990s and were often speculated to be about weather modification, though many also theorised that it was a government programme to test out poisons or deliver a chemical agent to their own populations — though, as experts have pointed out, dumping aerosolised chemicals kilometres from a target would be an incredibly ineffective, and remarkably visible, way of doing so.

However, accusations of weather modification from planes are not so readily dismissable. The only current attempt at weather modification, cloud seeding, does involve releasing silver iodide (Agl), a harmless and naturally occurring substance, from airplanes in the hope of producing raindrops (it’s efficacy, however, is questionable).

Clouds themselves can have significant effects on surface temperature, with one NASA study estimating that they generally cool the earth’s surface by about 5 degrees celsius.

In fact, after stricter environmental rules were enacted in 2020, a reduction in clouds formed from pollution in the wakes of ships appears to have caused a surge in ocean temperatures in the Atlantic, in what has been called an “unintentional experiment in geoengineering.”

So could a chemical sprayed by airplanes be used to create clouds and thereby change the weather? In theory, yes, though there is no evidence that this has been done over Ireland.

Last year, the European Commission’s Group of Chief Scientific Advisors released a scoping paper on the possibility of using this technology, a version of Solar Radiation Modification, or SRM.

However, the paper itself largely deals with the limitations of the technology, including legal restrictions.

“SRM does not reverse climate change and it could cause unintended climate changes (warming or excessive cooling), regional precipitation changes, harm the ozone layer, and impact human health and well-being,“ the paper warns. “Sudden and sustained termination of SRM (in particular SAI) would cause rapid climate change”

It continues: “The EU does not consider SRM as a solution, as it does not address the root cause of the problem, which is the increase in greenhouse gasses in the atmosphere. Even if technically feasible and proven safe, it would provide only a temporary relief, not a cure.

“In the current state of development, SRM deployment represents an unacceptable risk for humans and the environment.”

The paper asks that an investigation into “the risks and opportunities associated with research on Solar Radiation Modification and with its potential deployment” as well as how it should be governed, be completed in the third quarter of this year.

So, it seems that the EU is not ready to experiment with this technology. However, this paper does appear to have renewed interest in the subject of climate modification, and a steady stream of Irish social media posts speculating about it has been observed.

So, has Ireland begun experiments on its own?

This question was put to the then-Minister of State at the Department of the Environment, Climate and Communications Jack Chambers, last Thursday, by Senator Sharon Keogan, who said of her fellow senators “each and every one of us get emails daily on this particular issue.”

However, Chambers was able to provide the Seanad with a succinct response: “Met Éireann confirms that it has not conducted any climate or weather modification programmes and it is not aware of any such activities in Irish airspace.”

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