Not an expert, but my understanding is that the end of the last ice age led to an overall global average temperature change of +10°C.
For the current climate change, we've been calling +2°C catastrophic.
It is catastrophic: millions will die, species will go extinct, trillions will be spent updating infrastructure and rebuilding. But I believe that it's survivable.
> Not an expert, but my understanding is that the end of the last ice age led to an overall global average temperature change of +10°C.
Over what time period? 10°C in 10 million years is fine. In 10 years it would kill almost all life. The amount of change is inconsequential as long as the rate of change is small enough.
So let's go with 5°C over 2000 years, or 1°C over 400 years. Do you see the difference between that, and our current change of 1°C over 100 years (and accelerating)?
Yes, I do. But I also see significant differences in our level of technological sophistication and adaptability compared to Homo sapiens during the last ice age.
So our technology and so on will magically ensure our ecosystem doesn't die? We will find ways not only to adapt ourselves, but also to keep plants from dying due to sudden changes in climate, to keep animals from dying whose food sources have died out? We'll find magical solutions for all of these problems, whose complexity we still aren't close to fully understanding?
I can put a pot of water on my stove, but my hand in, warm the pot by 1°C, and I'll be fine. I can't do the same with an increase by 100°C.