Something left unsaid about Koutsoyiannis et al.

The latest in here is a shiny statistical model that disproves everything you thought about greenhouse gases causing climate change is Koutsoyiannis Demetris, Onof Christian, Christofides Antonis and Kundzewicz Zbigniew W.2022  Revisiting causality using stochastics: 1. Theory Proc. R. Soc. A 4782021083520210835 and Revisiting causality using stochastics: 2. Applications Proc. R. Soc. A.4782021083620210836

Of course, the classic was the unit root and Bart Verheggen's weight loss program but recently we have Statistics Norway trying it on, and just a year ago another ground breaking article

Demetris Koutsoyiannis is a well established, tho emeritus, professor of hydrology at the National Technical University in Athens, Christian Onof a rainfall guy at Imperial College, Antonis Christofides, also at NTU Athens and Zbigniew W. Kundzewicz, a pretty well known rainfall/hydrology person. Add to this that the Proc. R. Soc. A, ain't MDPI and a bunny knows the sharks will gather

So no surprise to find them at Curry's, with the birth announcement (well, first year anniversary) on Twitter, and the usual pile in. 

Naomi Oreskes and John Cook have a lot to answer for, if it was not for them pointing out that there is very little serious literature disagreeing with the IPCC consensus poor Eli would not have to wade throught this stuff 

The TL:DR 

The remaining real-world case study led to an important side product of the current research. This is the surprising finding that, while in general the causal relationship of atmospheric T and CO₂ concentration, as obtained by proxy data, appears to be of hen-oregg type with principal direction 𝑇 → [CO₂], in the recent decades the more accurate modern data support a conclusion that this principal direction has become exclusive

and the problem is the usual one. As Eli, and others pointed out (there are some useful references)

 We know from measurements that more CO2 is being emitted by burning fossil fuels than remains in the atmosphere. We also have measurements showing that ~105 _+ 8 Pg C from these emissions has been absorbed in the oceans* and the biosphere has i** and we have measurements and theory on how temperature and salinity affect CO2 partial pressure in the gas phase above sea water*** where a difference of 1C corresponds at best to a few ppm.

Of course we know that the atmospheric concentration of CO2 has increased from ~290 to ~430 ppm over the last 150 years.

This poses some obvious problems for any statistical treatment which claims that CO2 concentration follows changes in temperature

*Feely, R. A., Sabine, C. L., Takahashi, T., & Wanninkhof, R. (2001). Uptake and storage of carbon dioxide in the ocean: The global co~ 2 survey. OCEANOGRAPHY-WASHINGTON DC-OCEANOGRAPHY SOCIETY-, 14(4), 18-32.

**Amthor, Jeffrey S. “Terrestrial higher‐plant response to increasing atmospheric [CO2] in relation to the global carbon cycle.” Global Change Biology 1.4 (1995): 243-274 and especially the annual cycle

***Weiss, R. F., Jahnke, R. A., & Keeling, C. D. (1982). Seasonal effects of temperature and salinity on the partial pressure of CO2 in seawater. Nature, 300(5892), 511-513

Poking about and tossed up this comment on Koutsoyiannis et al. by Leif Åsbrink in the january 11 2023 issue of PRSA. It says pretty much what everybunny has been saying

From the information in [1] we can therefore draw a second conclusion: For timescales in multiple decades, the results in figure 14 have no meaning since the data span a far too short time. The differentiation has also suppressed slow changes. Common perception that [CO2] causes an increase in the temperature can thus neither be verified nor falsified. It is self-evident that the effect ΔT → [CO2], which is seen on a short timescale, will also be present on all longer timescales. A temperature change in the order of 0.4°C will cause a change in [CO2] of about 2 ppm, as measured on the derivatives.3 The temperature change over the 42 years is about 0.5°C while [CO2] has changed by about 80 ppm. Some other mechanism is likely to dominate on timescales of multiple decades. Hence, the common perception that increasing [CO2] causes increased T seems likely. . . . . 

Settled science’ is supported by many lines of evidence and it includes many more factors than [CO2] as causes of the increased temperature since pre-industrial times. CO2 is however considered to be the largest factor. ‘Settled science’ includes the phenomenon that increased T causes a modest increase of [CO2] (outgassing from the sea), which is detected in [1]. The statement ‘in the recent decades the more accurate modern data support a conclusion that this principal direction has become exclusive. In other words, it is the increase of temperature that caused increased CO2 concentration’ that appears in Discussion and conclusions in [1] is not supported by proper arguments in the paper.

https://royalsocietypublishing.org/doi/10.1098/rspa.2022.0529

This comment is notable for two things, all the references are to websites (inc. Roy Spencer’s blog) and there is no reply by Koutsoyiannis. 

Also, Eli can't find it being discussed most anywhere at all and certainly not at Curry's. The editors at Proc. T. Soc. A seem to have tossed Koutsoyiannis under the bus.