Besides any zone that makes you descend into eerie darkness (blood kelp, grand reef, ILZ corridor, etc) and the entire game at night, being near an area where Leviathans spawn.
More specifically, being near one's spawn point or territor…
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I'm pretty sure you can already slow down the ingame clock with console commands. It's something like "Speed 0.5" to go half as fast. You do have to reapply it every time you start up the game again, though.
After finding out how little you get punished for dying in survival, I started only playing in Hardcore mode. I only ever made it to the (then unfinished) PCF once, and ended up losing my PRAWN suit in the process.