Creationist Lies
Out of context: Reply #483
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Although, to be fair. Since of the Earth's atmosphere is out-of-balance with the conditions expected from simple chemical equilibrium, it is very hard to say what precisely sets the level of the carbon dioxide content in the air throughout geologic time. While scientists are fairly certain that a 100 million years ago carbon dioxide values were many times higher than now, the exact value is in doubt. In very general terms, long-term reconstructions of atmospheric CO2 levels going back in time show that 500 million years ago atmospheric CO2 was some 20 times higher than present values. It dropped, then rose again some 200 million years ago to 4-5 times present levels--a period that saw the rise of giant fern forests--and then continued a slow decline until recent pre-industrial time.