Based off a recent fall down a rabbit hole on the internet and my own thoughts: the oceans will rise and flood low level plains, forcing inhabitants to higher grounds (piedmont/mountains); technology will advance and most jobs will be run solely by some form of technology; by proxy, increased technology will lead to longer lives with questionable effects; the continents will fuse together once again; volcanoes will erupt erratically; the climate of earth will become too hot to support most life; the sun will eventually become a red giant and will either scorch or swallow earth; then it will become a white dwarf leaving earth (if it somehow survived the red giant stage) too cold to harbor life.
I often think about this and I probably shouldn't....