Andy Revkin over at dotearth, his more than lukewarm blog on the New York Times, has posted a critique of the announcement of a likely grand minimum in solar activity, written by NOAA solar scientist Douglas Biesecker. This page links the google doc and also a powerpoint slideshow.
Revkin says:
I’ll alert the group that came out with the prediction of a new minimum. This debate will need to play out in the peer-reviewed literature, of course.
And the Sun, in the end, will determine who’s right.
Well of course Andy, empirical data is the final arbiter. And naturally, the issue can now be kicked into the long grass while we wait for the journals to get around to publishing the resulting to and fro.
The thrust of Biesecker’s argument is the uncertainty inherent in the extrapolation of trends from short datasets. Something his colleagues at NOAA who draw conclusions about other aspects of climate change should take careful note of.
Biesecker says a couple of curious things in the document, including this:
Many people, including Dikpati et al and the cycle 24 panel predicted a ‘late’ start to cycle 24.
News to me. Dikpati forecast a very high cycle 24, and was, I seem to recall, part of the NSSTC panel which produced the first couple of frames of the ever-changing solar cycle 24 ‘prediction’ seen below. I guess we’ll let the mainstream heavyweights slug it out while we get on with the business of creating actually useful longer term prediction tools like the ones Theodor Landscheidt developed.
My thanks to talkshop contributor OrkneyLad for the latest version of this animated image.
Tallbloke's Talkshop 
Predictions of solar activity are much like predictions of sea ice in that there is enough ‘flex’ in the underlying theory/model to allow for a broad range of possible outcomes. This means that at least one ‘expert’ is likely to be close to the observed reality and this prevents the underlying hypothesis being seen to be falsified.
This behaviour is usually a sign that the theory/model is wrong in some major aspect – bit like French soldiers who mark the bullseye on their targets after they’ve fired their shots…:)
The scientists involved would make better progress if they started to look for alternative conjectures, rather than defending the current paradigm.
one thing missing from the calculations is the effect of Alfven waves generated by sun grazing or diving meteors that appears to ‘sap’ magnetic energy from the sun via CMEs.
since the association of meteors and CMEs seems to be the norm, it is likely that the Alfven waves connect to the CME point before the meteor arrives with the coup – de- gras (which is a result of the Alfven waves – rather than physical contact).
weaker suns invite an increase in meteors so that the weakness of a cycle would have to include a guess as to the availability of invitees
With the AID of some Kool the Sun will not cool… 🙂