[WhiskeyX]

The reprt of 400 ppm CO2 concentration is yet another fraudulent report Slate and the MSM failed to report when it was retracted as an error.

Premature 400 PPM fail-a-bration
Posted on May 13, 2013 by Anthony Watts

http://wattsupwiththat.com/2013/05/13/premature-400-ppm-fail-a-bration/

[Sir Napsalot]

I followed your link, there is another link in the comment section caught my eyes: (hat/tip: mwhite)

“There is no constant exponential rising CO2-concentration since preindustrial times but a variing CO2-content of air following the climate. E.G. around 1940 there was a maximum of CO2 of at least 420 ppm, before 1875 there was also a maximum.” (Source)

agere_contra also posted the same thing.