Noachian flood and the physics of water.

There are many that believe that the Noachian flood in the Bible actually happened despite there being absolutely no geologic evidence of such a global catastrophe happening, not to mention several contemporary civilizations completely failing to a) mention the event and b) being wiped out by it. Of course there's another reason to discount this event as happening, and it comes from physics

In order to flood the Earth to the height of the highest mountain you need a lot of water. Way more water than exists today. A simple calculation that subtracts the volume of a sphere with the radius of the Earth to the height of Mt. Everest from the volume of a sphere with the radius of mean sea level nets the volume of additional water to be about 4.52x10¹⁸ m³. That's a lot of water.

Now since people didn't notice this massive volume of water in the sky prior to the rains started it would have had to be in vapour form. This means that in order for rain to happen this vapour needs to condense. This requires a release of energy. The amount of energy released is easy to compute as all one has to do is multiply the mass of the water in kilograms, in this case 4.52x10²¹kg by the heat of vapourization for water which is 2270kJ/kg. This nets us about 1.03x10²⁸J of energy.

Now this energy wouldn't be released all at once, but over the 40 days given for the rains. From this we can work out the wattage of the heat given out by dividing the number of joules of energy by the number of seconds in 40 days which gives us a power of 2.96x10²¹W. From this we can work out how much heat each square metre of the Earth would be radiating by dividing the wattage by the surface area of the Earth which nets 5.82x10⁶W/m². For comparison the amount of energy the Earth receives from the Sun is about 1300 W/m².

From this we can now work out how hot a blackbody radiating at by using the Stefan-Boltzmann law. From this law and our calculated wattage nets us a temperature of about 3182K (2910C or 5270F). This is hot enough to basically melt the surface rocks of the Earth. The energy release would literally prevent rain from falling and would actually vapourize the water that was already here, and melt the rocks. There would be no need to flood the Earth as the temperature would be enough to sterilize the planet.

So the complete lack of evidence for a flood in either the geologic record or contemporary accounts is bad enough. That the heat generated by the rainfall needed to cover the Earth in that much water shows that it just didn't happen.