|"The earth is an open system receiving energy from the sun. The ozone surrounding the present earth absorbs the deadly, destructive ultraviolet light from the sun, permitting visible light to reach the surface and to be utilized by green plants. On the hypothetical primitive earth (evolutionists[sic] must believe[sic]) there was no oxygen, therefore, no ozone. Ultraviolet light would, thus, reach the surface of the earth, destroying all molecules and material necessary for the origin of life. The rates of destruction of all substances using my kind of raw energy vastly exceeds the rates of formation. The evolutionary origin of life is excluded." --- Reverend Duane Gish|
Concentrations of some of the most important early atmosphere
components would have been diminished by short wavelength, i.e.,
<2000 , ultraviolet photo dissociation. Atmospheric methane would
have polymerized and fallen into the ocean as more complicated
hydrocarbons, perhaps forming an oil slick 1 to 10 meters deep
over the surface of the earth.
If this occurred, very small concentrations of methane would predictably have remained in the atmosphere. About 99% of the atmospheric formaldehyde would have been quickly degraded to carbon monoxide and hydrogen by photolysis. Carbon monoxide concentrations in the atmosphere would have been small, however.
Carbon monoxide would have been quickly and irreversibly converted to formate in an alkaline ocean. Ammonia photolysis to nitrogen and hydrogen would have occurred very quickly, reducing its atmospheric concentration to so small a value that it could have played no important role in chemical evolution.
If all the nitrogen in the contemporary atmosphere had existed in the form of ammonia in the early atmosphere it would have been degraded by ultraviolet light in 30,000 years [later revised by J.P. Ferris and D.E. Nicodem to 100,000 - 1,000,000 years]. If the ammonia surface mixing ratio were on the order of 100,000 as Sagan has estimated, then the atmospheric lifetime of ammonia would have been a mere 10 years. It would also have been difficult to maintain substantial levels of hydrogen sulfide in the atmosphere. Hydrogen sulfide would have been photolyzed to free sulfur and hydrogen in no more than 10,000 years. The concentration of hydrogen sulfide in the ocean would have been further attenuated by the formation of metal sulfides with their notoriously low solubilities. The same photodissociation process would have applied to water to yield hydrogen and oxygen.
Some recent studies suggest that, through ultraviolet photolysis of water vapor, atmospheric oxygen did reach an appreciable fraction of today's concentration in early Earth times.
Thaxton, Charles B., Walter L. Bradley, Roger L. Olsen, The Mystery of Life's Origin: Reassessing Current Theories, Philosophical Library, New York, 1984, pp. 43-44.