Really? So you've checked this out?
Good, I have a few questions, which I'm sure you can answer.
On average, at any given time, how many millions of gallons of water are in clouds floating over the earth?
How many millions of gallons of water make up the ice at each of the poles?
How many millions of gallons of water are sitting elsewhere across the world in snowcapped peaks, etc.?
How many millions of gallons of water are in underground bodies of water?