“Engelbeen on why he thinks the CO2 increase is man made (part 4)“. Anthony pats himself on the back for letting someone with a “narrative contrary to the blog owner(s) view” post on his website. Of course although retired engineer Ferdinand Engelbeen happens to accept the scientific principles and evidence for increasing CO2 levels, he has similar ideas about how this has nothing to do with Global Warming. Which of course isn’t happening.

Regardless if that is man made or not, I think we agree that the influence of the increase itself on temperature/climate is limited, if observable at all.

Poor Ferdinand Engelbeen thinks that patiently explaining, in this post, how useful “background” CO2 levels are actually derived, how sampling locations and techniques dramatically diminish the value of many historical records, and how the ratio of stomata openings to the total number of cells on leaves are a poor proxy for CO2 levels, will stem the flow of ignorant commentary.

Good luck Ferdinand! And good luck with the nothing’s happening theory.

Hint to Anthony Watts: the d13C ratios show that the added CO2 has come from fossil fuel sources. Engelbeen explained it to you a week ago. End of story.