OAKLAND, Calif. — THE end is near.

At least, Hollywood seems to think so. When it comes to the steady unraveling of essential earth systems — ocean health collapsing, biodiversity plummeting and, of course, the fraying of the atmosphere’s stability — much of the political establishment continues to whistle past the graveyard. Filmmakers, meanwhile, are sending out an S O S: We’re doomed.

Is the premise fiction? Only partly. And not in the way you may think. The most fantastical thing about some of these films isn’t their doomsday scenarios. No, the real stretch is the idea that humanity — or at least some privileged slice of it — will be able to remove itself from the disaster.

The latest example is the writer-director Christopher Nolan’s epic sci-fi adventure, “Interstellar.” With Earth on the brink of collapse as crops wither and oxygen in the atmosphere dwindles, a team of astronauts race to distant galaxies in search of a new planet for the human race. Earth’s last survivors won’t starve, we are told. They will suffocate.

Such end-of-the-world scenarios appear so regularly in books and films that they are now their own mini-genre — cli-fi. The threats are not necessarily always climate related; the impending disaster in “Interstellar” seems to be as much biological as atmospheric.