Personally I doubt the accuracy of the 210 PPM figure from over a hundred years ago and how they came to that conclusion.
The same with their claims about global temperature average of a hundred years ago. What measuring apparatus was used and where were all the thermometers located?
If I can control the data input I can also control the data output.......
I don't think there was any significant event that caused a rise in PPM but rather the current 410 level is actually the norm since the science is sophisticated enough to actually read it as opposed to 100 years ago.....
That’s a discussion in the back and forth comments to the article with the author.
The article itself does a convincing job of showing what’s wrong with the IPCC model. The 14CO2 decay data from the nuclear test pulse is particularly convincing.
However, the article seems to say, that since the model is wrong, and the human contribution is accounted for, there is either a rise in natural CO2, or the historical data is wrong.
Some of the posters to the article make the latter assertion, saying that ice cores may track atmospheric CO2, but they underestimate it.
Things to follow going forward.
I guess a logical question is, “How long have we been directly measuring atmospheric CO2, and how much of our data is inferred?”