Category Archives: Multiproxy Studies

Taimyr – Linear or Nonlinear?

While I’ve got Esper open, here’s some thoughts on the division of cores and sites between "linear" and "nonlinear" – where I’ve been seeking an operational definition for some time. Herr Esper told Science: The split into linear and non-linear ring width series is shown in a supplementary figure accompanying the Science paper. The methods […]

Taimyr in Esper and Osborn-Briffa

The chronologies for Taymir in Esper et al [2002] and Osborn and Briffa [2006] differ – not a whole lot but enough to be noticeable. Esper provided measurement data for Taymir, while Osborn and Briffa have refused. The letter from Science said: The other three series contain some non-identical tree-ring series derived from the same […]

Another Inch at Sciencemag

Update: Continued here I just heard back from Science on the continuing and frustrating effort to obtain data from Esper et al. [2002] and Osborn and Briffa [2006], last discussed here . I got interesting but incomplete information in February and March. The latest installment is very disappointing in comparison even though, in my opinion, […]

Reverse Engineering Hegerl et al.

Lee, a new poster, complained that my attempting to guess the series in the CH-blend was insulting to Hegerl et al. [SM note – This sentence is added on Friday evening. I had a sentence somewhat like this in this post. Lee said that the sentence misrepresented his viewpoints – see one of his posts […]

When is an Upper Confidence Limit a Lower Confidence Limit?

An odd question, you say. It’s not something that usually expect in a statistical study. But hey, this is the Hockey Team, with statistics by Frame of climateprediction.net.

Hegerl et al in this week's Nature

There’s a new study by Hegerl et al. in this week’s Nature, which, among other things, describes the performance of something called the CH-blend, a secret blend of 12 proxies – a secret somewhere up there with the Caramilk secret. As I mentioned previously, I requested the identity of the sites in the blend as […]

Letter to Climatic Change

I was asked to review the Wahl and Amman submission in May 2005 and recently posted up my review here. The first recommendation in my review was that all Wahl and Ammann remove all arguments that depended on their rejected GRL article. They didn’t and now it’s come back and should haunt them. Despite providing […]

Alberta #3

In February 2006, Luckman and Wilson archived their STD chronology for the Athabasca Glacier, Alberta site (STD fits each tree individually; RCS fits trees in groups.) Rob Wilson wrote in criticizing an earlier post for, among other things, not showing their STD version and for how I implemented the RCS emulation for Esper et al […]

Alberta #2

There are 3 different versions of the Alberta site that have been applied in multiproxy reconstructions: 1) Luckman et al [1997] used in Jones et al [1998]; Crowley and Lowery [2000]; Briffa [2000]; 2) Esper et al. [2002] ; 3) the version used in Osborn and Briffa [2006], presumably from Luckman and Wilson [2005] and […]

The Alberta Site in Esper 2002

Here is some more analysis based on the Esper measurement data sent to me by Science on March 16, 2005 — this time on the “Athabasca” site, which refers to a location in the Rocky Mountains, Alberta near the Athabasca Glacier. This note is rather a status report, so that I keep track of what […]