Scafetta vs the IPCC

Great new application from WUWT contrasts the predictions of two models of global warming, Scafetta’s empirical resonance model and the IPCC general circulation models.

I was asked to make sense of this from Rahmstorf and Foster:
http://iopscience.iop.org/1748-9326/6/4/044022, referenced here at RC: http://www.realclimate.org/index.php?p=10475.

I haven’t read the paper in detail, and I find I have to do that to really assess it. So I can only comment on the general approach. Although it seems superficially plausible, its also somewhat novel, and so I am uncomfortable with it, as I don’t fully appreciate the statistical limitations.

IMHO only really scientific way to approach a question is to contrast between competing hypotheses, eg. the null versus the alternative, or other combination, such as the Scafetta vs IPCC above. Its clear, easy to understand and not so prone to biases.

But it seems like climate scientists are very creative in coming up with novel ways to justify their theory, and almost always fail to clearly compare and contrast the alternatives. That is their weakness, they are so damn convinced of CAGW, and shows they are generally ill-equipped with the expertise and training for conducting rigorous scientific analysis.

And of course, “creative” is meant not in the good sense.

  • Anthony

    I was discussing this paper with a Michael Brown at the Conversation until he decided to get insulting, which is his default position. Until then some of the discussion was interesting; the link is here:

    https://theconversation.edu.au/we-do-need-drastic-action-on-climate-change-a-response-to-the-wall-street-journal-5059

    • Davids99us

      I read them. I think what you are saying Anthony is that such things as TSI and SOI need to be correctly combined with temperature.  If F&Rs paper simply removed them in a regression, then that assumes that TSI is directly proportional to temperature, i.e. that there is instantaneous equilibrium.  Basic physics says you cannot do that in a dynamic model, where the temperature takes times, and sometimes a long time, to come into equilibrium with a change in TSI. 

      For example, it may have taken 50 years to surface temperature to have come into equilibrium with the grand solar maximum that has spanned a number of solar cycles.  If you just regress with TSI, you remove the proportional influence of the 11 year cycle, but do not remove the steady accumulation from the high TSI anomaly over the whole period.  Then you confound that residue with CO2 heating.

      So the correct approach would be to also regress against the integral of TSI, and then remove that as well and the direct TSI.

  • Alex Harvey

    Hi David,

    Did you see the new paper,

    Ljungqvist, F. C., Krusic, P. J.,
    Brattström, G., and Sundqvist, H. S.: Northern Hemisphere temperature
    patterns in the last 12 centuries, Clim. Past Discuss., 7, 3349-3397,
    doi:10.5194/cpd-7-3349-2011, 2011.

    http://www.clim-past-discuss.net/7/3349/2011/cpd-7-3349-2011.html

    I don’t understand how Foster and Rahmstorf can use statistics in lieu
    of an understanding of the underlying physics to deduce the underlying
    causes of the temperature observations.  Nothing in F&R (not that
    I’ve read it) could change the fact that solar effects, ocean cycles,
    ENSO and other phenomena relevant to the problem are poorly understood.

    It bugs me that this must be an obviously circular argument wrapped up in statistics that no one understands.  It bugs me that it’s obvious to me and yet no way to prove it.