Dimming the sun is a terrifying new industry

Researchers worry that a ‘rogue actor’ might just resort to solar geoengineering despite its poorly understood potential side effects.

- Lara Williams

Solar geoengineering, a bunch of techniques that aim to mask some effects of climate change by blocking sunlight, isn’t on the agenda for November’s COP30. It ought to be.

A record-breaking funding round for companies doing this stuff shows people are getting serious about trying to artificially cool the planet. That’s terrifying, especially when these businesses are largely unregulated.

In a recent poll of climate researchers, two-thirds said they thought there'd be an attempt to deploy large-scale solar radiation modification (SRM) by 2100. Only 9 per cent said there wouldn't be.

That’s a worrying reflection of woeful progress on cutting emissions, and pessimism about the future. After all, solar geoengineering can act only as painkiller, not cure, for the climate crisis. And it comes with a range of poorly understood potential side effects.

What’s even more bone-chilling about the New Scientist poll is that more than half of researchers reckon deployment will be driven by a “rogue actor” such as a private company, billionaire or nation state going it alone.

Although the idea was once on the scientific fringes, it’s gaining traction among tech bros.

Billionaire Elon Musk recently posted on X that “a large solar-powered artificial intelligence satellite constellation would be able to prevent global warming by making tiny adjustments in how much solar energy reached Earth”. I guess he means his own enormous fleet of Starlink satellites.

Millions have been spent on academic research into methods like stratospheric aerosol injection (SAI), in which a reflective material such as sulphur dioxide is sprayed into the stratosphere, and space mirrors, which are exactly what they sound like.