The Soon fallacy

As many will have read, there were a number of press reports (NYT, Guardian, InsideClimate) about the non-disclosure of Willie Soon’s corporate funding (from Southern Company (an energy utility), Koch Industries, etc.) when publishing results in journals that require such disclosures. There are certainly some interesting questions to be asked (by the OIG!) about adherence to the Smithsonian’s ethics policies, and the propriety of Smithsonian managers accepting soft money with non-disclosure clauses attached.

However, a valid question is whether the science that arose from these funds is any good? It’s certainly conceivable that Soon’s work was too radical for standard federal research programs and that these energy companies were really taking a chance on blue-sky high risk research that might have the potential to shake things up. In such a case, someone might be tempted to overlook the ethical lapses and conflicts of interest for the sake of scientific advancement (though far too many similar post-hoc justifications have been used to excuse horrific unethical practices for this to be remotely defendable).

Unfortunately, the evidence from the emails and the work itself completely undermines that argument because the work and the motivation behind it are based on a scientific fallacy.

Putting aside papers where Soon was only a minor contributing author, and the hopelessly slanted ‘forecasting principles’ papers with Green and Armstrong (see here for why they add nothing to the discussion), most of Soon’s work has been related to finding correlations of a very specific solar reconstruction (see figure below) to some observational time-series. There are very real criticisms that can be made of the solar forcing time-series he uses, and of course, of the cherry picking of specific time-series without mentioning that correlations to others (such as the global mean) are very low, but even accepting all that, there is a much more fundamental problem.

It is most succinctly highlighted in an article Soon wrote ‘It’s the Sun, stupid’ (not sure if it was ever really published anywhere, but he did send it to his contacts at Koch Industries). Towards the end he states:

The evidence in my paper is consistent with the hypothesis that the Sun causes climatic change in the Arctic.

It invalidates the hypothesis that CO₂ is a major cause of observed climate change – and raises serious questions about the wisdom of imposing cap-and-trade or other policies that would cripple energy production and economic activity, in the name of “preventing catastrophic climate change.”

It is the leap from the first to second sentence that drives Soon’s research – the notion that if you can find enough correlations to solar forcing, the impact of CO₂ must be diminished, if not obliterated altogether. But this is a fallacy. It is equivalent to arguing that if total caloric intake correlates to weight, that exercise can have no effect, or that if cloudiness correlates to incident solar radiation at the ground, then seasonal variations in sunshine are zero. The existence of one physical factor affecting a variable in a complex system says nothing whatsoever about the potential for another physical factor to affect that same variable.

Even if the correlations existed at the level Soon claims (and they don’t – see figure), it would still not indicate that CO₂ had zero effect, and indeed, it could never do so. The impacts of CO₂ on radiative transfer have been studied since the 1860s, and modern spectroscopic databases date to Air Force calculations for heat seeking missiles in the 1950s and have been validated by an enormous number of observations, both in situ and via remote sensing. The vertical fingerprint of the impact of increasing CO₂ (warming troposphere, cooling stratosphere) was calculated in 1967 by Manabe and Wetherald, decades before it was observed. None of this science disappears because a regional temperature series correlates for some short time with something else.

Figure 1. Updating the Soon (2005) correlations by correcting for an obsolete and almost certainly incorrect solar reconstruction (replacing with the SORCE reconstruction) and extending the temperature data to the present, shows an almost complete collapse of the initially impressive correlation (click for larger version).

The only way this might even begin to make sense would be if attribution of recent global warming was based purely on a linear regression of temperature to CO₂ (which it isn’t). Given that we know there are multiple drivers of climate operating (the sun for sure, but also volcanoes, aerosols, greenhouse gas changes, land use change, etc.) the only way to do attribution properly is calculate the physical fingerprints of each of these drivers across multiple variables and see which combinations provide the best fits. Indeed, this is indeed exactly what is done. This kind of attribution is not based on single-factor correlations and is even robust to errors of magnitude in the calculated responses.

Soon’s work has been singularly poor for over a decade, first coming to prominence with the Soon and Baliunas (2003) debacle in Climatic Research which led to the resignation of 5 editors in protest at the way the paper was handled (and see more here). Another case associated with some very obvious shenanigans was Dyck et al (2007). More recently, his presentations at Heartland’s pseudo-climate conferences have come under renewed scrutiny for their level of incoherence.

The odd thing about this is that there is real, and interesting, science to be done on the impacts of solar forcing on climate. The chemical feedbacks due to photolytic reactions in both the stratosphere and troposphere involving ozone, NOx, and water vapour, can have significant impacts. Exploring the tremendous complexities in aerosol formation and growth and impacts on clouds and whether that is mediated by modulations of cosmic rays is fascinating (if, as yet, inconclusive). Indeed, there is a current NASA call for proposals on exactly these subjects (Notice of Intent due March 13!). But every time another one of these spurious correlations is touted, or one more fallaciously reasoned argument is put forward, it makes it harder for serious scientists to get involved at all without being tarred with the same pseudo-scientific brush.

Moving on from this low-quality, pointless kind of solar forcing shtick can’t come ‘Soon’ enough.

References

1. W.W. Soon, "Solar Arctic-Mediated Climate Variation on Multidecadal to Centennial Timescales: Empirical Evidence, Mechanistic Explanation, and Testable Consequences", Physical Geography, vol. 30, pp. 144-184, 2009. http://dx.doi.org/10.2747/0272-3646.30.2.144
2. S. Manabe, and R.T. Wetherald, "Thermal Equilibrium of the Atmosphere with a Given Distribution of Relative Humidity", Journal of the Atmospheric Sciences, vol. 24, pp. 241-259, 1967. http://dx.doi.org/10.1175/1520-0469(1967)024<0241:TEOTAW>2.0.CO;2
3. W.W. Soon, "Variable solar irradiance as a plausible agent for multidecadal variations in the Arctic‐wide surface air temperature record of the past 130 years", Geophysical Research Letters, vol. 32, 2005. http://dx.doi.org/10.1029/2005GL023429