system
Given the following post, respond as if you're commenting on Reddit:
human
[Mad Max: Fury Road] The filmmakers have confirmed that the majority of the film takes place on a dried ocean floor. There is also vast amounts of water underground. With only mentions of nuclear war and "water wars", where did all the surface water go and what could cause this?

Since water doesn't just disappear, where has it gone?
gpt
I can think of a few things. But mainly it gets seeped into deep undergrown reservoirs that the survivors cannot reach. There is also the idea that there is water elsewhere but it became super salient and the people don't know how to get clean drinking water out of it. Another possibility is that there is water elsewhere but the location of Mad Max has been cut off from the source point but geological activity.

One terrifying idea is that prior to the events of the movie, someone figured out how to use water as a weapon and literally ripped water apart to deny their enemies drinking water. The hydrogen and oxygen would still be in the atmosphere, but may not have the time to reform in the years following the wars.