Giving the lie once more to the canard that ALL scientists (at least, all those not in the pay of Big Oil) share the IPCC orthodoxy, here is a very impressive review of the case for a solar mechanism.Though a highly technical article, p99, et seq, are intelligible enough to a layman.
Ultraviridian carbophobes are not going to like this one, as can be seen from this brief excerpt:- Could it be that the signals, or at least the quasi-100 000-year component, are not driven by orbital parameters? Could internal terrestrial phenomena (e.g. GHG) or external celestial causes (e.g. varying solar activity and/or cosmic ray flux) be the ultimate climate drivers on at least some of these time scales?
At first glance, the GHG proposition squares well with the Antarctic (Petit et al., 1999; Siegenthaler et al., 2005; Spahni et al., 2005) ice core data. The correlations between δ18 O and δD of ice (climate proxies) and the concentrations of CO2 and CH4 in enclosed air bubbles are impressive (Figure 52).
However, these correlations are discernible only if viewed at resolutions in excess of 1 000 years. Higher resolution records for all seven glacial terminations studied to this day show that the rise in CO2 postdates the warming by several hundred to 2 800 years (Fischer et al., 1999; Monnin et al., 2001; Mudelsee, 2001; Caillon et al., 2003; Vakulenko et al., 2004; Siegenthaler et al., 2005).
Consequently, CO2 is likely a product of the ≈100 000-year climate oscillations, not their cause.
PS It apears the paper was completed before Henrik Svensmark produced an experimental verification of his detailed cosmic ray-cloud mechanism (announced, with great irony, in the proceedings of the VERY green Royal Society), so any residual doubts expressed by the authors may already have been greatly alleviated
