I suspect that people raised with the idea of global warming have an advantage in knowing that the human race might well one day die out, that it is not necessarily immortal.
On the other hand, perhaps not. I remember learning about global warming. I don’t remember the specific details of what I learned, or even if it was at all accurate, but I do remember learning about it. And I thought something along the lines of, “There’s a fair chance everyone’s going to die if we don’t all do something about this.”
And I looked around.
And even the people I knew who believed in global warming—which, considering my social circles, consisted of pretty much everyone—seemed not to really see this. Even the ones who learned the exact same things I did, from the exact same place (that is to say, school) just seemed to assume that everything would, by necessity, just turn out all right.
After a while of this, I just gave up.
I wasn’t raised explicitly atheist—that is to say, when I was young, no one told me, “God does not exist.” (Though I could conceivably have overheard it when someone wasn’t talking to me.) But I was also certainly not raised theist. And I was taught (via very aggravating, though now I recognize also useful, conversations with my dad) to have good arguments. If I said, “So, everyone X, right?” as the beginning to an argument, he’d say, “Oh? Why do you say that?”