I read several articles where scientists have developed air scrubbers (articles
here and
here). So now they can remove the Co2 from the air, but now what can they do with it? They could bury it in the empty old oil chambers, or could they could launch chunks of Co2 into space and out of Earths SOI?
Now we get to the interesting part - the solutions. Instead of whining about the trouble we're having - let's solve it!
I think launching into space takes too much energy: there are other solutions that are more energy friendly. Remember: you can't use fossil fuels for generating your energy, or otherwise the net effect will be even worse than doing nothing.
I read about a chemical process that can create (m)ethanol from CO2, water and oxygen(*). The net reaction equation is the inverse of burning (m)ethanol, and about the same as producing the alcohol as bio-fuel. So, when powering the reaction with solar energy, it's about as useful as bio-fuel, but maybe it uses available ground surface more effectively.
Now, (m)ethanol is most useful as a fuel, but when burning it, the CO2 will enter the atmosphere again(**). This isn't necessarily bad, as we need a good alternative for gasoline, but it doesn't
reduce the amount of CO2 in the end.
There are projects for storing CO2 underground. The problem is that CO2 is a gas, while the oil where it came from was a liquid. And gases are about 1000 times as voluminous as liquids and solids. The high pressure underground will help a lot, but I doubt whether it will really work.
I found another approach: bind it to minerals. There are large amounts of minerals on earth that spontaneously absorb CO2, without gaining much volume. Only, normally this process is very slow, as it only happens on the surface of the rocks. I read a proposal to pulverize this rock into tiny pieces to increase its surface, and dump it into the oceans. Oceans absorb CO2 effectively, but they become saturated. The rocks will greatly improve the capacity of the oceans.
(*) On Wikipedia, that is. And it gave me more the impression of a 19th century scientific curiosity, not something that is ready to be used on an industrial scale.
(**) Even when drinking ethanol-containing drinks, biological processes will finally break it down to CO2