A paper by Nicola Scafetta in the Journal of Atmospheric and Solar-terrestrial Physics is reviewed at http://wattsupwiththat.com/2011/11/10/aurora-borealis-and-surface-temper… .. is set to expand the climate debate by drawing in solar flares and aurora borealist records. Basically, the claim is that oscillations in mid latitude auroras between 1700 and 1966 occurred in a cycle of some kind, at intervals that marry into instrumental global surface temperature records. The further claim is that aurora records reveal a physical link between climate change and astronomical oscillations in general. There is a known luni-solar tidal effect, a planetary modulation of the heliosphere effecting cosmic ray flux reaching the earth and/ or of the electric properties of the ionosphere. The latter has the potential of modulating global cloud cover which drives climate oscillations. In particular, a 60 year cycle is evident since AD1650 – in all climate and astronomical records. Concluding, Scafetta says that between 60 to 70 per cent of warming since 1970 is natural – induced by astronomical mechanisms.
Anthony Watts is not convinced and refers to dubious cycles and says a series of short time forecasts might be useful. Scafetta's earlier paper, along similar lines, was scoffed at by the climate science community – but Watts concludes, time will tell.