MBH98 used three Jacoby tree ring chronologies from Alaska: Four Twelve (ak031) – discussed here, Arrigetch (ak032) and Sheenjek (ak033). Sheenjek will be discussed in this article. In our compilation of MBH98 in 2003, we observed that the Sheenjek chronology archived at NOAA Paleo was not the same as the “grey” version used in MBH98. […]| Climate Audit
We’ve long discussed the bias imparted by ex post selection of data depending on whether it went up in the 20th century. Likening such after-the-fact selection to a drug study carried out only on survivors. The Jacoby and d’Arrigo 1989 network was a classic example: the original article reported that they had sampled 36 northern treeline […]| Climate Audit
In numerous ancient Climate Audit posts, I observed that all MBH98 operations were linear and that the step reconstructions were therefore linear combinations of proxies, the coefficients of which …| Climate Audit
In today’s post, I will report on some excellent work on MBH98 by Hampus Soderqvist, who discovered an important but previously unknown Mike’s Nature Trick: Mann’s list of proxies…| Climate Audit
Continued from here. The Dirty Laundry residual datasets for AD1000, AD1400 and AD1600 were each calculated using Mann’s “sparse” instrumental dataset, but the resultant sigmas an…| Climate Audit