Four scientists who have spent over a century collectively studying the physics of climate just want you to understand something. Stop trying to hack the weather.
There is a loud conversation happening in places like the Guardian, suggesting it is “time to talk” about geoengineering. They mean those techno-optimistic quick fixes. The ones that promise to offset the carbon emissions we haven’t actually stopped putting into the atmosphere yet.
Solar geoengineering gets all the headlines. Inject things into the stratosphere to block the sun. But the problem isn’t just one idea. It’s a whole cluster of desperate schemes designed to “fix” the chaos we created by burning fossil fuels.
Some proposals are almost absurd in their ambition and cost. Damming the Bering Strait.
Most threaten the most fragile parts of our planet. The polar environments. The ice. And if we actually built these systems? We would lock Earth into a physically precarious state. We would add a new, destabilizing weapon to an already violent political world.
Here is the hard truth most proponents ignore.
Carbon dioxide lingers. Once we emit it, it stays for a very long time. A large chunk of it will still be baking our planet thousands of years from now. It is sticky. Permanent, almost.
Solar geoengineering does the opposite. The substances we spray into the air fade in years.
That sounds good, doesn’t it? We can flip a switch. Turn it off when we realize it is destroying rain patterns or hurting crops. Right?
Wrong.
It takes twenty years just to build the infrastructure needed to make these interventions work. Two decades.
By then? We are dependent on the machine. We have to keep running it. In a world already prone to conflict. We cannot afford for it to stop.
If we do stop. If a war breaks out or the power grid fails or society just collapses… all that pent-up warming comes out at once.
Scientists call it the “termination shock.”
It is catastrophically rapid warming. The mask falls off.
Solar geoengineering does not buy time. It does not help us decarbonize. It just buys a fragile, temporary reprieve from the heat we are still creating. Other schemes have the same flaw. They require maintenance for centuries. Five hundred years from now? The Bering Strait dam might crumble. The carbon will still be here.
So let’s think about this.
How many unforeseen disasters can happen in fifty years? How many more in five hundred?
Are we really okay playing Russian roulette with the global climate? Are we willing to commit generations to maintaining these fragile systems, without fail, forever?
The authors of this piece know the science. Really well. They have done the math. Since 1991, the IPCC has gathered tens of thousands of experts. Physicists, economists, climate modelers. They did due diligence on CO2. They looked at it carefully.
It took a hundred years of emissions just to prove that we were causing climate change. It took even longer to pin the blame on human activity. Only in 2015 did the world accept the diagnosis in Paris. In 2023, the UN finally admitted fossil fuels were the culprit.
We know what we did.
Now? The geoengineering lobby wants to hammer the climate with new tools we barely understand. Aerosols. Clouds. Rainfall patterns. We don’t have the science.
“Climate model simulations can provide an indication… but no reassurance.”
We are flying blind.
No rigorous assessment has explored different solar geoengineering scenarios. There is no formal comparison of how the climate reacts to these shocks. Let alone the local weather effects.
The models themselves don’t agree.
If we inject aerosols for ten years? The result is unpredictable. Global cooling could be less than 1°C. It could be 3°C.
That is a huge swing.
Is it less than 3°C of rapid, chaotic cooling? Or is it less than 10°C of catastrophic error? (Note: an earlier draft of this argument contained a typo suggesting 30°C cooling—a laughably wrong number that shows how unchecked these claims can become).
We don’t know.
Small scale “safe” experiments won’t help. They are naive ideas.
The forces of nature are massive. Ocean currents redistribute heat on a planetary scale. Cloud patterns fluctuate wildly. Any tiny experiment would be swallowed whole by the weather.
If we are serious? We need the scientific foundations.
We don’t have that.
What we have is a tsunami of money going the wrong way. Funding for engineering. Funding for deployment. Not for understanding.
The juggernaut is rolling. It ignores warnings from top scientific academies. The UK Royal Society. The US National Academy. The French Academy of Sciences.
All of them said: proceed with extreme caution. There are massive uncertainties. There are ethics issues.
Look at the UK Aria agency.
It pumped £60 million into geoengineering programs. The goal? Technology development. Often working with for-profit companies.
And now we see startups. Venture capital.
Stardust. An Israeli-US company raised $60 million. They want to deploy solar geoengineering soon.
Reflect Orbital. They want giant mirrors in orbit. They say it’s for “illumination” but the tech is identical to sun-blocking. They want in on the cooling credit market.
None of this has governance.
There is no law. No oversight. Just profit motives driving planetary intervention.
Should we hand the planet to venture capitalists? To private firms with no legal obligation to explain themselves? No need for public scrutiny?
This is folly.
It distracts us. It wastes resources.
As one of these experts put it:
“When you’re in a climate hole… stop digging.”
Also stop burning fossil fuels.
That’s the whole job.
Raymond Pierrehumbert
Julia Slingo
Michael Mann
Valerie Masson-Delmotte
Raymond Pierrehumbert (Oxford University), Julia Slingo (former Met Office Chief Scientist), Michael Mann (UPenn), and Valerie Masson-Delmote (Laboratory for Climate and Environmental Sciences) are leading climate scientists.
