[simonh]

I don't believe it's going to kill a lot of people. The planet went through this before during the Paleocene-Eocene Thermal Maximum[0]. Basically a quantity of carbon roughly equal to our industrial output estimate up to 2100 or 2200 was released into the atmosphere over about 20k years. It stayed there for several hundred thousand years, raising global temperatures by 8 degrees. We're talking aligators and crocodiles living in jungles on Antarctica. Massive die-outs of microbes in the oceans due to acidification and sea levels rising. 70m of sea level rise is locked up in polar ice and then there's also thermal expansion.

None of that is going to happen in our lifetime. But the lifetime of our great grandchildren? There's a good chance. After all, this isn't the first time. However we will have several centuries to adapt. The real issue is we're destroying the natural environment faster than it can possibly adapt or evolve, but we'd be doing that even without climate change.

[0]https://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Therm...