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Could that imply that you have a bias error in your understanding of Eschenbach and McIntyre because your understanding is based more on the interpretations pre

by nkurz 8y ago

Could that imply that you have a bias error in your understanding of Eschenbach and McIntyre because your understanding is based more on the interpretations presented at ClimateAudit than from the primary literature? Certainly. I actually started by reading MBH98 (after a friend interviewed Hughes) and I found it statistically very weak. I then discovered McIntyre's pre-ClimateAudit site at the time he was working on his rebuttal. Discovering someone else who was bothered by the same flaws (and was able to discuss them in a more rigorous form than I could) predisposed me to view him in a positive light. I'd like to think my continued positive impression of him has to do with the strength of his arguments since then, but probably at least some part is path dependent bias. And yet the 'hockey stick' remains in all the analyzes. The issues with post-hoc screening are separate from his initial criticisms, and are about statistical principles rather than the resulting graphs. McIntyre isn't saying that you only get a hockey stick if you screen out certain proxies. Rather, he thinks the analysis is overly sensitive to a small number of problematic "stripbark" series in the American West. If you include these series (or a small number of alternatives), you get a blade; if you leave them out, you don't. He believes that since most of the other proxies are only weakly tied to temperature, they average out to a mostly flat red noise that forms the historically flat "handle". I don't feel qualified to make his full argument, though. While I tried to keep up with the primary literature at one point, I haven't been reading much lately, and I've never been as deeply into it as McIntyre himself. My goal was simply to say that I think that both he and Eschenbach have some good points to make, that both are interested in finding the truth rather than spreading misinformation, and that they should be read and considered rather than being rejected out of hand.

eesmith 8y ago
Thank you for your considered response. MBH98 was 20 years ago. https://en.wikipedia.org/wiki/Hockey_stick_graph https://en.wikipedia.org/wiki/Hockey_stick_graph goes into details about the various analyzes of MBH98 and later, including criticisms and counter-criticisms. The Moberg 2005 analysis I referenced above is one of them, which used wavelet transforms instead of PCA. It found similar conclusions as MBH99, the extension of MBH98. > A 2010 opinion piece by David Frank, Jan Esper, Eduardo Zorita and Rob Wilson (Frank et al. 2010) noted that by then over two dozen large-scale climate reconstructions had been published, showing a broad consensus that there had been exceptional 20th century warming after earlier climatic phases, notably the Medieval Warm Period and Little Ice Age It then adds that more reconstructions have been done since then, again following the broad consensus. they should be read and considered rather than being rejected out of hand. This goes back to my original objection, which is that the g'g' etc. poster didn't point to something to read, other than "Willis Eschenbach's work over on https://wattsupwiththat.com/ https://wattsupwiththat.com/ ". I can certainly reject out of hand the undirected suggestion to read hundreds if not thousands of blog posts without having some solid reason to believe it's worthwhile, especially given that several of the poster's other comments on the topic seemed to be wrong, and internally inconsistent.

by nkurz 8y ago

eesmith 8y ago

Thank you for your considered response. MBH98 was 20 years ago. https://en.wikipedia.org/wiki/Hockey_stick_graph https://en.wikipedia.org/wiki/Hockey_stick_graph goes into details about the various analyzes of MBH98 and later, including criticisms and counter-criticisms. The Moberg 2005 analysis I referenced above is one of them, which used wavelet transforms instead of PCA. It found similar conclusions as MBH99, the extension of MBH98. > A 2010 opinion piece by David Frank, Jan Esper, Eduardo Zorita and Rob Wilson (Frank et al. 2010) noted that by then over two dozen large-scale climate reconstructions had been published, showing a broad consensus that there had been exceptional 20th century warming after earlier climatic phases, notably the Medieval Warm Period and Little Ice Age It then adds that more reconstructions have been done since then, again following the broad consensus. they should be read and considered rather than being rejected out of hand. This goes back to my original objection, which is that the g'g' etc. poster didn't point to something to read, other than "Willis Eschenbach's work over on https://wattsupwiththat.com/ https://wattsupwiththat.com/ ". I can certainly reject out of hand the undirected suggestion to read hundreds if not thousands of blog posts without having some solid reason to believe it's worthwhile, especially given that several of the poster's other comments on the topic seemed to be wrong, and internally inconsistent.