Government Eyes Risks of Foreign Weaponisation of Sun-Dimming Technology

Ministers are examining the threat of a hostile foreign power potentially weaponising solar geoengineering technology, amid rising global interest in sun-dimming techniques to combat climate change.

According to a ministerial letter seen by The Telegraph, the UK Government wants to understand the risks posed by an “independent or third-party actor” deploying solar radiation modification (SRM) methods to reflect sunlight away from the Earth.

Such actors could include nations making unilateral moves to curb global warming – or more alarmingly, adversarial states seeking to exploit the technology for geopolitical disruption.

Solar geoengineering, also known as solar radiation modification, involves artificially cooling the Earth by reflecting sunlight back into space. One of the most studied methods involves spraying aerosols into the upper atmosphere.

Kerry McCarthy, Climate Minister, stated in the letter: “The UK is a longstanding leader on climate action and an active international collaborator in scientific research. The Government recognises the need to understand the risks and impacts of [solar radiation modification] approaches that could be deployed by an independent or third-party actor. Robust scientific evidence is essential for informing responsible and inclusive governance.”

Matt Ince, Associate Director at Dragonfly Intelligence, noted that governments have long feared the unpredictable consequences of unilateral deployment. But a new concern is the potential for intentional misuse.

Mr Ince said: “In a context where we’ve had, for example, Russia increasingly expanding its use of hybrid warfare activities, it’s possible – not immediately, but down the line – that they may look to broaden and diversify the types of activities that they’re conducting, to include more novel types of activity of which solar geoengineering may be one.

“Not least because of its relative affordability and the feasibility of conducting it, but also because it would allow a relative degree of plausible deniability.

“We’ve seen migration patterns being intentionally influenced by the Russian state as a way of trying to push more pressure on to European countries.”

Mr Ince added: “That could be something like purposefully creating an oil spill within a busy shipping lane using Russia’s shadow fleet. But on the more imaginative end of the spectrum it’s feasible it could involve deliberately trying to use solar geoengineering technologies in order to be able to destabilise the climate within a European state and in so doing, create chaos and a sense of discord, and force countries to become more inward focused.”

Critics of SRM argue the risks are poorly understood, and that such methods could detract from vital global efforts to cut greenhouse gas emissions. More than 560 scientists have signed a letter calling for an “international non-use agreement” on solar geoengineering.

The letter warns: “Without effective global and democratic controls, the geopolitics of possible unilateral deployment of solar geoengineering would be frightening and inequitable.”

Recent studies suggest that solar geoengineering could have unintended consequences for UK agriculture.

Historical events such as major volcanic eruptions have shown that injecting aerosols into the atmosphere can reduce direct sunlight, which in turn limits photosynthesis and lowers crop yields. While solar dimming may offer a cooling effect, it does not necessarily offset the damage caused by reduced sunlight.

There are also concerns that altering atmospheric conditions could disrupt rainfall patterns vital to UK farming. As real-world trials progress, the risk to domestic crop productivity and food security cannot be ignored.

Dan Marks, Research Fellow in Energy Security at the Royal United Services Institute, highlighted major governance challenges.

He said: “There are a few challenges with the way the technology works. If you are putting aerosols in the air, for example, then the Earth spins and you can’t limit that to your national boundaries. And even if you could, weather systems don’t stop at borders.

“So if a country decided to deploy that kind of technology, then there is a real question of how do you treat that legally? How do you treat it diplomatically?

“Equally, what if an Elon Musk or an activist group decided to do it, and decided to do it in the middle of the ocean? How do you govern that?”

Lt Gen Richard Nugee, the Ministry of Defence’s former non-executive director for climate change and sustainability, is part of a group examining the potential weaponisation of the technology.

He said: “No country has yet tried to weaponise the technology, quite possibly for a couple of reasons. It is seen to be very expensive for no defined and guaranteed output, and also it is not possible to predict the outcome – there are too many variables.”

The Telegraph has also reported that Aria – the UK’s Advanced Research and Invention Agency – is funding over £50 million worth of outdoor field trials, including experiments in brightening clouds to reflect solar radiation as a potential climate mitigation tool.

However, Minister McCarthy emphasised that the UK Government's position remains “not to deploy [solar radiation modification]”.

Source: The Telegraph