If you want a real explanation for why CO2 levels are not the threat the warmists make them out to be; look at page 24, of the source article, here:
Note, there's a logarithmic (exponential) relationship between the levels of CO2, and the greenhouse effect. The incremental impact of CO2 drops off very fast. Warmists try to hide this fact — so that they can grossly exaggerate the effect.
Researcher: Basic Greenhouse Equations "Totally Wrong"
"Miklós Zágoni isn't just a physicist and environmental researcher. He is also a global warming activist and Hungary's most outspoken supporter of the Kyoto Protocol. Or was."
"That was until he learned the details of a new theory of the greenhouse effect, one that not only gave far more accurate climate predictions here on Earth, but Mars too. The theory was developed by another Hungarian scientist, Ferenc Miskolczi, an atmospheric physicist with 30 years of experience and a former researcher with NASA's Langley Research Center."