The IPCC base their claims about how much warming is ‘in the pipeline’ on the rate that carbon dioxide is eventually removed from the atmosphere, the ‘e-folding time’. This is different to the time it takes for any emitted joe-average co2 molecule to be re-absorbed in the carbon cycle, and reflects the assumptions made about the way the carbon cycle operates.

The IPCC relies on the ‘Bern model, which was cooked up many years ago by Bert Bolin and other atmospheric scientists of the warmist persuasion. The Bern model makes assumptions which lead to a very long e-folding time of hundreds of years, a figure which has been disputed by several able researchers, and discussed here at the talkshop in previous posts.

Now talkshop co-blogger Tim Channon has made novel use of data which shows what has happened to the radioactive carbon 14 isotope carrying co2 levels since the atmospheric…