Tell that to the girl who died because her friends made her drink like a gallon of water to get her to come down off a bad high. Humans have a delicate electrolyte balance in their bodies, and too much water upsets that.
I thought someone said that we were actually at the tail end of an Ice Age still. Hot desert time, here we come!
That being said, the Earth is way bigger than us, and she can fend for herself.