[blueflow]

85% of the prehistoric time earth was like that, its called greenhouse earth or acyrogenic climate. Dinosaurs lived when it was around 10 degrees hotter, and they did not die from that.

Right now we are living in a icehouse earth where polar caps are a thing, which is not the case in a greenhouse climate.

[infinite8s]

However you are forgetting about continental drift. 100M - 200M years ago there was much more land concentrated at the poles (where the climate would have been more amenable to life) - https://www.theatlantic.com/technology/archive/2013/09/what-...

[blueflow]

And nowadays we got Eurasia and North America lined around the North Pole.