I think we need to do this until we develop large scale underground CO₂ sequestration.
Unfortunately even if/when we completely stop producing CO₂, it takes at least several centuries until levels go fully back down to natural levels by themselves.
Pumping SO₂ into the stratosphere should be able to regulate global temperatures to reasonable levels while we develop effective CO₂ sequestration.
Unfortunately SO₂ injection is incredibly controversial, as it triggers the "don't mess with nature" taboo, especially among people who have seen Jurassic Park, and affects the whole planet, including those who don't want it.
We do actually know that SO₂ breaks down in the stratosphere in 1-2 years, because we've studied when volcanoes injects it. It also doesn't cause acid rain because it's above the rain cycle.
But these facts are very hard to get across to people.
That SO₂ breaks down so quickly is one of the reasons SO₂ injection is probably not a good idea.
Suppose we start putting enough SO₂ in the stratosphere to halt warming or at least slow its growth down.
I can almost guarantee that the response of the current US government would not be "Whew...now that we've averted the near term problems we were facing from climate change we can get to work on seriously getting rid of most fossil fuels use".
No, it would be "Great! We can now get rid of those cancer causing wind farms and ugly solar farms and go all in on a 100% fossil fuel economy featuring a massive increase in coal. We should have been doing that all along but enough people believed in the global warming hoax to slow us down. Now we are free of that!".
We'd need ongoing increasing SO₂ injections to counter this, and all it would take is something to disrupt that for a few years and then all that increasing warming that has held back by those injections would come roaring back. But we'd be getting that warming increase over a short term instead of a longer term, making it much harder to deal with.
Unfortunately even if/when we completely stop producing CO₂, it takes at least several centuries until levels go fully back down to natural levels by themselves.
Pumping SO₂ into the stratosphere should be able to regulate global temperatures to reasonable levels while we develop effective CO₂ sequestration.
Unfortunately SO₂ injection is incredibly controversial, as it triggers the "don't mess with nature" taboo, especially among people who have seen Jurassic Park, and affects the whole planet, including those who don't want it.
We do actually know that SO₂ breaks down in the stratosphere in 1-2 years, because we've studied when volcanoes injects it. It also doesn't cause acid rain because it's above the rain cycle.
But these facts are very hard to get across to people.