I’ve mentioned before that the flawed ‘hockey stick’ temperature reconstruction is used to reduce the role of the sun in climate change. Little pre-industrial temperature variability would help support the claim that 20th century warming is mainly anthropogenic in origin. Scafetta and West have recently published a continuation of their phenomenological approach to estimating the role of total solar irradiance (TSI) in climate change, which compares TSI reconstructions with temperature reconstructions.
Interestingly, Scafetta and West conclude that: “if we assume that the latest temperature and TSI secular reconstructions, WANG2005 and MOBERG05, are accurate, we are forced to conclude that solar changes significantly alter climate, and that the climate system responds relatively slowly to such changes with a time constant between 6 and 12 years. This would suggest that the large-scale computer models of climate could be significantly improved by adding additional Sun-climate coupling mechanisms.”
I should point out that solar irradiance is only one potential solar effect on climate and the IPCC rate the ‘level of scientific understanding’ (LOSU) of ‘solar irradiance’ as ‘low.’ Even the contrived Lockwood and Frohlich (2007) paper pointed to the possibility of an unknown ‘solar amplifier’ and the expected fall in future solar activity. Furthermore, it is possible that equivalent solar forcing is ‘different’ to greenhouse gas forcing.
Anyway, the JGR paper entitled: ‘Phenomenological reconstructions of the solar signature in the Northern Hemisphere surface temperature records since 1600’ by N. Scafetta and B. J. West can be found here. It’s a good read, so enjoy!