I just ran across this 6 month old post by Herrmann:
Herrmann writes:
Furthermore, in congruence to the Flood Theory, Water evaporated in the sky ( as evident from Gen 1:7 "And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. ") This could be cause to slow the penetration of UV rays, and thus extend the lifetime of the occupants of the planet earth.
I decided to reply as I have heard this claim recently, in one case presented at a public creation seminar. The water vapor canopy idea, made popular by Morris & Whitcomb in 1961 (as far back as I can trace it), essentially claims that the Earth was once surrounded by a 'shell' of either water vapor or (in some models) liquid water. The idea is that this shell would serve three purposes. 1) The water would screen out UV and other harmful radiation thus enabling people to live centuries 2) The vapor would trap heat making the entire Earth a lush tropical paradise, and 3) The vapor would increase the amount of 'good' light (I assume they mean long wavelength) again contributing to plant growth.
I am not going to elaborate on the physics of such a canopy but want to point out a big flaw in the biological aspects of such. Water and water vapor screen out
long wavelengths and is nearly invisible to short wavelengths. This is a critical aspect in oceanography called light attenuation with depth. Red light is long wavelength and is the most important for green plants. Water (ocean) and water vapor (clouds) block red light very well. Shortwave radiation, including UV, passes right through water and water vapor. This is why you can get nasty sunburns on cloudy days. A world with a water canopy would support few if any green plants and the UV would tend to cook surface life. It is however true that such a canopy would heat things up a bit, as recent evidence suggests for
Venus.
"I have seen so far because I have stood on the bloated corpses of my competitors" - Dr Burgess Bowder
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