Climate Auditby Steve McIntyreSkip to contentHockey Stick StudiesStatistics and RContact Steve McProxy DataCA blog setupFAQ 2005Station DataHigh-Resolution Ocean SedimentsSubscribe to CAEconometric ReferencesBlog Rules and Road MapGridded DataTip JarAboutCA Assistant« Older postsThe “Canonical” Varve Thickness SeriesDec 4, 2013 – 3:33 PMShi et al 2013 use the following five varve thickness series, all of which have become widely used in multiproxy series since their introduction in Kaufman et al 2009: Big Round Lake and Donard Lake, Baffin Island; Lower Murray Lake, Ellesmere Island; and Blue Lake and Iceberg Lake, Alaska.  Some of these proxies have been discussed from time to time, with an especially detailed discussion of Iceberg Lake (see tag here.)  The figure below compares a simple scaled average of these five series to the Hvitarvatn varve thickness series (inverted so that the Little Ice Age is shown as “cold” rather than warm. See accompanying discussion of Hvitarvatn here. Whereas Miller et al reported that the 19th century at Hvitarvatn was the period of greatest glacier advance in the entire Holocene, the “Kaufman five” show 19th century levels similar to the 11th century medieval period, with an anomalously ‘warm” 20th century:Figure 1. Top – average of five Shi et al varve thickness series; bottom – Hvitarvatn varve thickness (inverted).  All in SD Units.There is no “common signal” in the Kaufman Five according to common methods. The median inter-series correlation is 0.00605, with negative interseries correlation as common as positive interseries correlation. If one examines the eigenvalues of the correlation matrix – a useful precaution in assessing whether the data contains a “common signal” – there are no eigenvalues that are separable from red noise as evident in the barplot below.Figure 2. Eigenvalues of (Kaufman Five) Varve Thickness SeriesDespite the overwhelming lack of common signal according to these criteria, the average of the Kaufman Five has a distinctly elevated 20th century. Here is a plot of the Kaufman Five.  The lack of correlation and lack of significant eigenvalues is evident in the plot, where there is little in common among the series except for one feature: the 20th century in each series is somewhat elevated relative to the 19th century.  (As noted above, the average of the five series has a somewhat elevated 20th century, but is relatively featureless in centuries prior to the 20th century, especially in comparison to the well-dated Hvitarvatn series.)Figure 3. Five Varve thickness series used in Shi et al 2013 (SD Units.)When parsed in detail, each of the Kaufman Five has troubling defects, some of which I’ll briefly discuss today and which I’ll try to follow up on.The Iceberg Lake, Alaska series has profound inhomogeneities, especially in its 20th century portion. A major inhomogeneity