1/9 That Inman paper is, indeed, rubbish, but not because we know too little about the carbon cycle. It's because the practical "first half-life" of anthropogenic CO2 is only about 35 years. That means the "adjustment time" 𝑻 = 35/ln(2) ≅ 50 years. https://twitter.com/ncdave4life/status/1432983045687160836…

2/9. I discussed this topic in more depth in this comment, on WUWT: A. https://wattsupwiththat.com/2022/04/09/explaining-mauna-loa-co2-increases-with-anthropogenic-and-natural-influences/#comment-3495301… and also in this pair of comments, on Dr. Curry's blog: B. https://judithcurry.com/2021/10/06/ipcc-ar6-breaking-the-hegemony-of-global-climate-models/#comment-960901… C. https://judithcurry.com/2021/10/06/ipcc-ar6-breaking-the-hegemony-of-global-climate-models/#comment-960902… .

3/9. The "first half-life" of ≈35 years means that if our CO2 emissions suddenly ceased, it would take about 35 years for the CO2 level to decline halfway toward 290 ppmv (i.e., to ≈355 ppmv), and about 50 years for the CO2 level to decline 63% of the way toward 290 ppmv.

4/9. That's the result Prof. Richard Lindzen reported during the Q&A (3rd video) of this excellent lecture: ● Part 1: https://www.youtube.com/watch?v=hRAzbfqydoY… ● Part 2: https://www.youtube.com/watch?v=V-vIhTNqKCw… ● Part 3 (Q&A): https://www.youtube.com/watch?v=69kmPGDh1Gs… (including discussion of CO2 atmospheric lifetime)

5/9. That's also the approximate result that Dr. Roy Spencer found: http://www.drroyspencer.com/2019/04/a-simple-model-of-the-atmospheric-co2-budget/…

6/9. That's also the approximate result that I got, first with a program to simulate CO2 levels, based on the historical CO2 removal rate as a function of CO2 level, and then with a modified version based on Dr. Spencer's model. Here's the source code: https://sealevel.info/CO2_Residence_Times/…

7/9. Ferdinand Engelbeen reported roughly the same result. He also wrote the clearest and most thorough examination of the cause of rising CO2 concentrations which I've found, here: http://www.ferdinand-engelbeen.be/klimaat/co2_origin.html…

8/9. What Inman called "fallout from burning fossil fuels" is actually beneficial! Climate activists often claim that anthropogenic CO2 has a residence time of "centuries," or even longer. But such claims are based on integrating the "long tail" of its theoretical decay curve.

9/9. Integrating the "long tail" is silly, because the long tail would only be relevant if CO2 levels were ≤ 340 ppmv — in which case the Earth would be suffering from a very severe CO2 deficit. The long tail would just slow the worsening of that deficit. https://twitter.com/ncdave4life/status/1215246375040049152…