Comment by oorza
I mean, if I had Elon Musk money, I'd build some kind of giant carbon capture mechanism. Perhaps I'd buy the largest basalt quarry I could find and start sequestering carbon at a planetary scale. It would cost a ton of money, but I'd do it in secret. If it worked, eventually it would show up on the scales, and I'd emerge from the shadows. This particular method of carbon capture could potentially work at a planetary scale and could potentially be done in secret, at huge cost, but the only blocking factor today is money.
https://eos.org/articles/basalts-turn-carbon-into-stone-for-...
This is the answer to carbon storage by the way, people just do not know about it. There's more than enough reactive mineral sites on the planet. The process is basically just dissolving CO2 into water, heating it, and soaking basalt in it to allow crystals to form. The water becomes heavier than ground water and can simply be poured into the Earth. The unsolved problems are optimization problems: direct air capture of CO2, using saltwater, that sort of thing.
If the world's billionaire class decided to buy carbon sequestering, we could have global CO2 levels returned to 1900 levels within a decade or two. The technology exists, the economic willpower does not.
https://www.bbc.com/news/world-43789527
> Potentially, basalt could solve all the world's CO2 problems says Sandra: "The storage capacity is such that, in theory, basalts could permanently hold the entire bulk of CO2 emissions derived from burning all fossil fuel on Earth."
Having said all of that, this is likely the most dystopian option. It's the "tech bails us out, yet again" solution because we could deploy it thoroughly enough that we can solve climate change without addressing any of the existential issues that got us here. The right combination of corporate+government partnership commercializing this technology and making it mandatory is a very plausible way to arrive at "there's 4 corporations on Earth that run the show" a la Aliens.
It's very much the wrong time to scale carbon capture. Doing some pilot plants for research is a good idea, but if your goal is to see the effects on the global plots, you should be working on something else.
There's a sibling with the long-form reasoning. The problem is that we are pushing a lot of new carbon into the atmosphere, you just won't be able to scale anything enough and there's a really big opportunity cost to try to push the tide away.