Warwick Hughes has a post claiming that there were high CO2 levels in the atmosphere in the 1940s “contrary to IPCC science” pointing to a something by E-G Beck. Here’s Beck’s graph:
Now, a normal person looking at that would conclude that chemical measurement of CO2 concentrations was not particularly accurate, but Beck concludes that there were huge fluctations in CO2 that ended by some strange coincidence exactly when they started making more accurate measurements.
Eli Rabett explains what is wrong:
Here we will briefly summarize the paper and then point out why it is wrong, not only wrong, but a) the information Beck points to has been well known for a very long time b) the reasons for the earlier measurements being much higher than the current ones have been well known for at least 50 years and c) these problems were the original impetus for the Mauna Loa observatory (MLO) series. In other words, Beck is quite right about the measurement methods and quite wrong about their interpretation. Local knowledge can be very important.
William Connolley also has a few words.