Sulfur dioxide aerosol injection in the stratosphere until carbon capture and decarbonization can catch up.

We desperately need an energy inexpensive way to sequester atmospheric carbon underground in stable (mineral) form. Hopefully we’ll see progress from Climeworks or similar concerns in this space.

https://iopscience.iop.org/article/10.1088/1748-9326/aae98d/...

I wonder if Venusians tried the same thing which lead to the concentrations of SO2 we see in Venus' atmosphere.

Someone should make this a movie.

As long as so many coal plants are happily smoking and even more are about to be build, I think the first priority is to shut them down and replace those, instead of experimenting with the already quite instable global climate, by injecting more chemicals.

And after we stop emmitting CO2, we can focus on artificial decarbonization. But I would rather invest in proven technology, like reforesting first.

I read something recently about seeding beaches with crushed limestone which accelerates CO2 absorption through weathering or something.

I think that was what the movie Snowpiercer was about. It ended badly before the start of the movie, with an ice age.

In the field of active climate engineering one can try dispersing aluminum [0] or/and (synthetic) diamond micro-particles [1] in the stratosphere to reflect some of the Sun's light back into space. Especially useful because the effect is temporary and self-healing. An accidental "ice age" will resolve on its own in few months after one stops replenishing the stratosphere with the particles.

[0] https://acp.copernicus.org/preprints/15/11799/2015/acpd-15-1...

[1] https://www.nature.com/articles/nature.2015.18634

> Any control theory guys out there with suggestions?

Nothing small and cheap. We've been applying a massive forcing effect by adding billions of tons of CO2 per year to the atmosphere over decades. It's going to require a commensurate amount of effort, at the very least, to swing the needle back in the other direction.

Our best bet might be something crazy like using nukes to set off volcanoes to generate an ongoing low level 'nuclear winter' type effect. We'd have to be careful to pick the right volcanoes, though, to minimize the CO2 emitted by said volcanoes.