Termination Shock – The Existential Danger Of Geoengineering

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On June 19, 2026, four respected climate scientists — Raymond Pierrehumbert, Julia Slingo, Michael Mann, and Valerie Masson-Delmotte — penned an article for The Guardian that explained the danger lurking within geoengineering schemes. Not only will they be frightfully expensive, but once begun, they cannot be allowed to lapse. They must continue for a century or more to avoid disastrous changes in the environment that could endanger life on Earth as we know it. The scientists call that threat “termination shock.”

How difficult the transition will be to a sustainable global economy was on display in Bonn, Germany this week, where climate talks in advance of the COP 31 conference later this year turned rancorous. “We have seen side-stepping and stalling,” said UN climate chief, Simon Stiell. “We’ve seen geopolitical tensions wash through these halls. We simply cannot afford to reopen previous decisions, to renegotiate existing targets, or to backslide. It’s cooperation, not fierce competition, that we need.”

A group of nations led by Saudi Arabia and including India objected to language reaffirming climate science. India — where extreme heat is killing more and more people every year — is objecting to a reference to climate science? That is insanity!

Sivendra Michael, speaking on behalf of the Pacific Island nations, said, “We are hearing voices in these rooms that are doing their best to undermine science. Anyone blocking references to science, they are not our friends. There are powerful interests desperate to protect their wealth and influence. We are seeing certain countries holding the [COP] process hostage as vulnerable people suffer heat stress and storms, droughts and famine.”

Geoengineering And Governance

The four climates scientists zeroed in on precisely the danger of letting economic self-interest dictate the response to a warming planet. Here’s what they had to say:

If we are to seriously consider geoengineering, then we need to make sure that the scientific foundations are in place. But for the most part, this is not the kind of research we are getting in the new tsunami of funding. What we are getting instead is funding targeted at developing the engineering technology for deployment, regardless of the consequences of what that deployment may be.

The solar geoengineering techno juggernaut rolls on, with what seems to be a complete disregard for what the damage might be to the planet, and despite several important assessments from leading scientific academies (to which we belong), such as the UK Royal Society, US National Academy, and the French Academy of Sciences.

Each has highlighted the major uncertainties, core ethics and governance issues, urging great caution. This is particularly true of the £60 million geoengineering program funded by the UK’s Aria agency. Aria’s chief aim is technology development, and indeed many of the geoengineering projects they are funding are being done in collaboration with for-profit companies.

Even more ominous is the explicit entry of venture-capital funded for-profit startups seeking to make money from solar geoengineering deployment in the near future. The Israeli-US startup Stardust has received more than $60 million in venture capital, and their business model assumes near-term deployment. And then there’s Reflect Orbital which wants to put giant mirrors in low Earth orbit; they are pitching sales of illumination rather than solar geoengineering, but the technology is identical and we doubt it will be long before they try to get in on the “cooling credits” game.

All of this is happening in the total absence of governance. There are pious calls for governance from some of the pro-geoengineering researchers, but what is the path to get there? Is it governable at all? It is the height of folly to invest in developing the technology — even if we knew what might work — that only serves to enable unrestricted, profit-motivated deployment by outfits such as Stardust.

As private companies whose technology is subject to little regulation, they and their backers have no legal obligations to submit themselves to public scrutiny nor to provide any assurances on ensuing climate impacts. Will these technologies be carried out devoid of any serious scientific understanding of the consequences and of social, legal and political concerns?

All of this is a huge diversion of resources and deflection from the task at hand. As one of us likes to say, when you’re in a climate hole, stop digging … and burning fossil fuels. It really is, at some level, that simple. [Emphasis added.]

Hammering Away At Climate Science

The authors lament, “Now proponents of geoengineering are proposing to bash the climate with a whole new hammer, and one that engages some of the most poorly understood aspects of the climate system, including aerosols, clouds and regional rainfall patterns. We know that this would trigger much more uncertainty on outcomes, in particular in the case of poorly planned, unmanaged, uncoordinated injections of various substances in the high atmosphere, with no governance framework. Surely, we should insist on the same level of scientific diligence as has been devoted to understanding the regional consequences of greenhouse gas emissions.”

Yes, you would certainly think so, but you would be wrong. “So far there has been no rigorous modelling assessment to explore different solar geoengineering scenarios and no formal inter-comparison of the sensitivity of the climate to such interventions, let alone the impacts on regional weather and climate variability,” the scientists wrote.

“What we do know is that the few models that have been used so far do not even agree on what level of intervention might be required, nor what the response will be. After only 10 years, for the same stratospheric aerosol injection, global cooling can be anything from less than 1C to as much as 3C — a change more rapid than anything we have seen so far from carbon dioxide emissions. We are essentially flying blind.”

Should we be worried yet? Maybe so. “The notion that small-scale ‘safe’ experiments can answer any of the important questions about the magnitude and effects of a deployment is fundamentally naive,” the scientists said. “Any meteorologist or oceanographer knows that the massive forces involved in the global climate system — such as the great heat redistributing currents of the ocean and atmosphere, or year-to-year fluctuations in cloud patterns — will swamp the effects of any experiment and provide no indication of the efficacy and the risks of deploying solar geoengineering.”

The War On Science Is Powered By Greed

What we are seeing is the fruition of a decades-long, fossil fuel funded, war on science. The result is not only ebola and screw worm outbreaks that were both preventable, but countries like the UK backing away from its EV goals because of political pressure applied by Big Oil. And let us not lose sight of how AI-driven social media has made undermining science easier than ever.

Humans seem convinced they can ignore the changes in climate that are occurring everywhere around the globe with increasing frequency. Instead, they look to autocrats to protect them, despite those powerful people promoting more of the behavior that got us into this mess in the first place. Careful readers will note that the tech bros, with all their trillions in wealth, are doing nothing — NOTHING! — to address the problem of an overheating Earth in any meaningful way.

Who Are These Scientists?

Why should we listen to anything these scientists say? Take a moment to read their professional qualifications and then decide whether you find them credible:

• Raymond Pierrehumbert is Professor of Planetary Science at the University of Oxford, and was a lead author on the IPCC Third Assessment Report, and the US National Academy’s first assessment report on solar geoengineering. He is a Fellow of the Royal Society
• Julia Slingo was formerly Chief Scientist of the UK Met Office, and was awarded the Rossby Medal of the American Meteorological Society among other prestigious awards. She has received nine Honorary Doctorates including from Cambridge University. She is a Fellow of the Royal Society and is Dame Commander of the Order of the British Empire, and was a reviewer on the recent Royal Society report on solar geoengineering.
• Michael E Mann is the Presidential Distinguished Professor in Earth and Environmental Science at the University of Pennsylvania, and Director of the Center for Science, Sustainability and the Media there; he is a Member of the US National Academy of Sciences and Foreign Member of the Royal Society
• Valerie Masson-Delmotte is Directeur de Recherche at the Climate and Environmental Sciences Laboratory; she has been co-chair of IPCC Working Group 1 during AR6, and co-author of the French Académie des Sciences geoengineering report and a co-author of a peer-review assessment of polar geoengineering options.

Are you going to believe them or some AI chatbot telling you how wonderful “clean beautiful coal” is? The choice is yours. Guide yourself accordingly.