Read Karolygate I first
Hi Raphi and Joelle,
Following some email discussions with Mike Mann and helpful discussions with you both last week, there appear to be several different approach es that we can take with revising the Australasian temp recon paper. I am going to go through some of them briefly, and then raise some suggestions for further data analysis that might be needed.
1. Amend the manuscript so that it states the actual way that the proxy selection was done, based on correls that included trends and were significant at the 5% level. The calibration was also done using the full data variations, incuding trends, over the calibration period. As Mike Mann says below and in the attached papers, this is a common approach. Don't seriously address the proxy selection for detrended data
2. Revise the manuscript to present results for reconstructions based on both proxy selections for full correls and proxy selections for detrended correls. Expand the paper to show both sets of results and explain why the full correls are better.
3. Re-do the analysis for proxy selection based on what the manuscript says, proxy selection based on detrended carrels, which gives only about 9 selected proxies and only one prior to 1400. No reliable reconstruction prior to 1400.
4 . Redo the analysis based on proxy correlations with local/regional temps at interannual and decadal timescales, not the Australasian area average; select proxies that have strong local temperature signals, then average the proxies to get the area average temperature. This approach is like what Raphi is doing for the SH paper, I think.
My preference is now for 1. or 2. above, and not for 3.....
Now re-read proposition #3 -- the one that concedes that, if the study had been done as advertised -- only nine proxies would have been relevant, with just one of those purporting to define climate prior to 1400AD. Obviously, that's not going to save the research and get the paper published.
Karoly's preference is to .... ignore that option!
Now look at option #2, one of Karoly's two favoured options, and don't forget that the paper originally sold the notion that Australian temperatures were at a 1000-year high on the strength of allegedly "detrended" data. That detrending wasn't done, which is why the paper had to be spiked, so now Karoly's idea is for everyone concerned to insist un-detrended numbers are the better option.
Just coincidentally, that approach saves the headline-grabbing claim that Australia is hot as Hades and poised to get a whole lot worse.