There’s always something unsettling about a disaster film. It’s not the notion of nature (or man) creating chaos, and thus calamity, for all the members of our unsuspecting society. It’s not the death, though that’s a horrific given. It’s not even the idea that what we are seeing could be the extinction of the entire human race.
No, the really nasty bit is the concept of survival, the “what if?” after the planet freezes, the tidal wave hits, or the nuclear holocaust ends. As they often say, those who are killed will be the lucky ones. Those left behind face the nightmare of rebuilding and reconsideration, recognizing that, while they made it, many, many more did not.