I think there was some kind of water in the atmosphere, too. Kept the earth “moist” and protected the planet from solar radiation - could account for the long lives of people during the time. Less radiation, less nuclear degradation.
Possibly. I think there was a pretty think atmosphere made up heavily of water vapor. I’ll find the verse, but it did exist before the flood.
Wasn’t it called a water canopy, or possibly just a canopy? I know I’ve heard that term before in connection with the flood account.