A major volcanic eruption is the only significant event which would lead to a reduction.

Heat balance can also be achieved by investing $10b a year to mimic volcanic activity

Disclaimer : Will cause white sky and unknown health effects.

Don’t get me wrong : we may or may not have to do this one day but it can only be a temporary solution in a too late transition scenario. It’s not a solution on top of our current fossil based economy else that would just be a time bomb.

If we keep having exponential growth in solar for another 15 years, we will be in a fine position to transition. But better to start asap and prevent runaway feedback loops.

And by start, I mean do tests and research. That is currently banned.