zlacker

https://en.wikipedia.org/wiki/List_of_extinction_events

https://en.wikipedia.org/wiki/Clathrate_gun_hypothesis

Citation: The associated period of massive carbon release into the atmosphere has been estimated to have lasted from 20,000 to 50,000 years. The entire warm period lasted for about 200,000 years. Global temperatures increased by 5–8 °C.[21]

The hot-models Sabine referred to are in range of 4.8 - 5.6 if I'm not mistaken...

>>pk-pro+(OP)
So, to avoid engaging in a Gish Gallop on this issue, I'm going to ignore the specifics except to point out that neither of those links says anything about human extinction at all.

It is reasonable to be concerned. But deploying easily-refuted hyperbole makes your (our!) cause MORE likely to be ignored as crackpot nonsense, not less.

>>ajross+DV1
Do you really mean that humans can survive without ecosystem? Mass extinction events are causing chain reactions ... I do not care about the causes. I'm not a climate activist. I'm just an average guy that can't do a squat and tired to be afraid for my children's future. I just accepted the fact that humanity will destroy itself sooner or later. I do not see any point in expecting wonders.