The macro challenge is that we have already overshot and the IPCC appears to be massively understating the current state. According to Hansen et. al.'s Global warming in the pipeline [under peer review], "Equilibrium global warming including slow feedbacks for today’s human-made greenhouse gas (GHG) climate forcing (4.1 W/m2) is 10°C, reduced to 8°C by today’s aerosols. Decline of aerosol emissions since 2010 should increase the 1970-2010 global warming rate of 0.18°C per decade to a post-2010 rate of at least 0.27°C per decade." For context, this 10°C is over the next 1500 years, but it does imply at least 4.3°C of warming by 2100.
> But if every fraction of a degree matters, shouldn't we also be at least continuing if not scaling up these albedo-increasing changes?
Humanity is running the experiment in real time with a sample size of one. Aerosol dimming is good but acid rain is bad: we have a bad vs a worse choice so someone will be harmed, thus any project has liability and the default of doing nothing happens.
> But if every fraction of a degree matters, shouldn't we also be at least continuing if not scaling up these albedo-increasing changes?
Humanity is running the experiment in real time with a sample size of one. Aerosol dimming is good but acid rain is bad: we have a bad vs a worse choice so someone will be harmed, thus any project has liability and the default of doing nothing happens.
https://arxiv.org/abs/2212.04474 if you want some light reading.