If it's a positive feedback loop, then why hasn't there been a runaway greenhouse effect in the past? Something must have stopped it. What was that?
> Concretely, there are farmers at the edge of the Sahara, who are adapted to a semi-arid conditions, and when the Sahara moves south, then they have to deal with desert conditions.
Yes, they will. They'll have to move. The Sahara didn't use to be a desert for all of human history, it used to be fertile at one point. Now it isn't anymore, so we don't have agriculture there. So what?
> Similar, when the Great Barrier Reef moves south, then there are dive centers without a reef north of the new location.
First-world problems...
> So we will have to adapt to a warmer climate anyhow, but not cutting down emissions is an entirely unforced error, it makes global warming worse, without any concrete benefit.
No concrete benefit? You mean, besides the fact that our entire standard of living rests on the fact that we can emit CO2 more or less undisturbed?
> Cutting down emissions is precisely the "smaller fallout of manmade climate change" you are arguing for.
Not if you take into account the standard of living of the people calling the shots, right here and now.