The Talk.Origins Archive: Exploring the Creation/Evolution Controversy

The Vapor Canopy Hypothesis Holds No Water
Paul Farrar
Bill Hyde

The Vapor Canopy Hypothesis Holds No Water
By Paul Farrar

In this short and, I hope, simple note I will discuss the physical implications of the often proposed "vapor canopy" explanation for the source of water for Noah's Flood as recorded in "Genesis".

Noah's Flood is alleged to have covered the mountains of the earth to a depth of 15 cubits (about 8m). To have covered Mt. Everest it would have required a depth of water of about 9km above sea level. If the flood was only required to cover the mountains in Urartu (Ararat), where Noah's boat is said to have settled, about 5km of water would be needed.

The "vapor canopy hypothesis" states that before the flood, the water existed in the atmosphere as water vapor. The flood occurred when this vapor condensed and fell as rain, flooding the earth. The flood subsided later, various explanations being given for where all that water went.

First, let us look at atmospheric pressure. For the earth's atmosphere, the pressure is almost exactly hydrostatic, since it is held to the earth by gravity and velocities are too low to significantly change the pressure. In plain language this means that the air pressure at any point is equal to the weight of the air in a unit area column above that point. At sea level, air pressure in US engineering units is about 14.5 pounds/sq inch because a column of air one inch square extending to the top of the atmosphere weighs (Guess what!?) 14.5 pounds. On top of Mt. Everest, the pressure is lower because the lowest and densest 9km of the atmosphere is below that point.

Now the "vapor canopy" would form a part of the atmosphere, being a body of gas (water vapor) gravitationally held to the earth. It would in fact be most of the pre-flood atmosphere. There would have to be enough vapor to form 9km of liquid, when condensed, and, therefore the vapor would weigh as much as 9km of water. The pressure at the earth's surface, where Noah and family lived, would be equal to one atmosphere PLUS the weight of a 9km column of water of unit area. This is equivalent to the pressure 9km deep in the ocean. What is this pressure? Well, each 10m of water is roughly equivalent to one atmosphere, so the pressure would be 900 atmospheres. The atmosphere would also have a composition of about 900 parts water vapor to one part of what we call air today.

How could an atmosphere almost 100% water vapor not condense? The temperature would have to be raised to the point where the partial pressure of water equals 900 atmospheres, i.e. the boiling point at that pressure. So we find Noah et al. living in a 13,000psi boiler. Is this credible?


The Vapor Canopy Hypothesis Holds No Water
By Bill Hyde

Someone writes:

"Radiocarbon" does not form from cosmic rays, the carbon-14 drops in from the sky itself.

C-14 forms in the reaction:

N-14 + neutron --> C-14 + H

where the free neutrons are generally produced by cosmic rays. So the canopy-promoting Jehovah's Witnesses are correct that such a canopy would foul up C-14 dating. However, it would also have many other effects, none of which are observed. I would add:


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