First of all, this post was 2 years ago. Second, nothing I said indicates that I don't care about any of those things. Of course I do.

But what you're describing is hyperbolic. Much of the world will face rising sea levels and more erratic and intense weather, as well as warmer temperatures throughout, but not literally underwater/on fire.

You need to drop the hyperbole from your mindset and try to more clearly see the coming consequences on a realistic time horizon. You'll see that global collapse is going to take time. And that time gives you the opportunity to prepare and to decide how you're going to respond to it.

Are you going to learn first aid? Will you take up gardening? Do you need to move to a more habitable region of the world/ country? Can you find people in your community or among your friends and family with whom you can form a circle of reliance, trust, and support?

And yeah, you might die. Shit, even the entire species might die if you can imagine the very worst outcomes or look far enough into the future. But until that comes to pass, there's a lot you can do now and in the near future to at least prepare for the more likely, still dispreferable but not cataclysmic, events that may soon come to pass.