[goatlover]

I may have overstated the degrees, but there was significantly more CO2 in the atmosphere thanks the prior major extinction from volcanic activity. It was very warm, and yes the dinosaurs evolved over millions of years, but the point is that it wasn't so extreme that animals couldn't survive, or there wouldn't have been dinosaurs, reptiles, mammals.

> Ok and what are you going to eat?

Stuff you can grow higher up or indoors.

> And use to power your cooling tech?

Solar, wind, geothermal, nuclear if there's a plant nearby.

> And how will you create fresh water?

Either live near a body of water or pipe it in.

> And where will you acquire raw materials to build things?

This will be harder as global trade will be seriously impacted and there won't be as many people to extract raw materials. But if we're talking smaller groups of humans, then maybe from scavenging existing things not in use or have to make use of local resources.

> And how will you survive the severe weather?

Sturdy shelters or caves. Not everyone will of course. My point is the entire planet won't become inhospitable. You could live up by the artic circle where there's water and grow things that can't grow there now. Might have to ship the soil in, though. There will be more passages in the artic with sea ice gone.

[meh8881]

You are imagining a world where people live in caves but we still have global shipping routes and large construction projects and nuclear reactors?

[goatlover]

I imagine a world where people have decades to figure out what part of the planet remains hospitable for human life. So places like Canada, Russia, the Himalayas, Rockies, Andes, Iceland, etc. The bigger problem will be fighting over those locations and the scarcer resources. But some groups of people in some condition will survive.

That might include local industry and northern shipping routes. Nuclear reactors or solar farms could have been setup decades before. Shelters don't have to be caves. They can be any sturdy structure. It's not like bad weather is going to blow or burn everything down across the entire planet.

I don't see how Earth becomes totally inhabitable for any realistic climate change scenario, including asteroid impact, nuclear winter or super volcanoes. There will always be locations that are survivable. We know this because animal and plant life has survived previous global extinctions on land, and humans have survived ice ages, which are arguably worse for global civilization.

[meh8881]

Most of the world becomes uninhabitable or volatile during that lead up where the world is getting hotter. Not decades where it’s fine and then too hot. The coast lines will rise pretty quickly. Most fish will die. Most agricultural centers will become unfarmable.

Sure you can make a bunker and live off of supplies. But you should not expect any substantial infrastructure or long distance travel to remain. You will not have fuel. You will not have steel. You will not have farms. You will not have water infrastructure, and ocean water will begin to pollute sources while others dry up. You will not have mega fauna to hunt. Most large plants will die. Your generation facilities will quickly become unuseable.

Sure there will be small plant life and critters and life will adapt. But nothing that a human population will be able to survive in. Living off of dwindling supplies is in a sealed off environment like guy on mars doesn’t count as surviving meaningfully imo.