Author Archives: Stephen McIntyre

Kaufman’s "Classical" Log Regression

I observed yesterday that I had been unable to replicate the archived version of Kaufman’s Hallet Lake series – something that I thought was due to a change in the archived version (since the NCDC archive noted that a new version had been archived in Nov 2008.) This turns out not to be what happened. […]

Five Alaskan BSi Series

At the second meeting of Kaufman’s PIs, one of the scientists plaintively asked: But shouldn’t we aim to do a synthesis that is only lake seds (at least as first step)? This logical building block was pushed aside (thereby allowing Briffa’s Yamal series to be recycled for the nth time) on the following grounds: some […]

Kaufman's BSi Selection

Below is a plot comparing sediment BSi (biological silica) to depth (cm) from two of Kaufman’s lakes (done by different students). I’ve shown it by depth (rather than ascribed age) since the dating of these sediment series is not without some hairiness. I’ve shown equal lengths for each lake, both covering at least 800AD-present on […]

Is Kaufman 'Robust'?

A common meme in Team-world these days is that any issues or errors are minor and that none of them “matter”. As we peel back the layers of Kaufman et al, this is the first line of Team defence. The rhetorical impact of Team reconstructions largely derives from the modern-medieval differential: is it in the […]

WGIII and those unarchived comments and RE reports

At the beginning of September, I was copied an email discussion reporting the online publication in Climatic Change of a paper by Warwick McKibbin, David Pearce, and Alison Stegman.   What was notable about this paper was that it was submitted in September 2005.   What for readers of this site, perhaps, was unremarkable was that it […]

The Kaufman Backstory

The backstory to the development of the Kaufman et al 2009 reconstruction is pretty interesting. A few years ago (after the MM criticisms of paleoclimate reconstructions), the US National Science Foundation sponsored the sampling of 30 Arctic lakes in a standardized way. It’s remarkable to compare the original population to the data sets used in […]

Kaufman et al: Obstructed by Thompson and Jacoby

A CA reader sent me an email, noting the following entry in minutes of a meeting. M Loso inquired about Lonnie Thompson’s ice core data. These data are not presently available but will be investigated by Caspar. This comment is minuted in a meeting of PIs leading up to Kaufman et al 2009 – a […]

Kaufman's Stick: Iceberg Lake Varves

In the first post on Kaufman et al, I observed that, like other Team multiproxy studies, its HS-ness is contributed by only a few series. As shown below, a composite of 19 out of 23 Kaufman proxies does not yield an “unprecedented” late 20th century (tho it yields an elevated late 20th century.) A composite […]

Sea Ice – Sept 2009

Continued from here . On August 19, 2009, NSIDC published the following August forecast of sea ice minimums by the leading climate modelers around the world. The majority of modelers predicted that 2009 sea ice minimums would be below 2008 and one (Arbetter et al) even predicted that 2009 would break the 2007 record. The […]

Kaufman and Upside-Down Mann

Kaufman et al (2009), published at 2 pm today, is a multiproxy study involving the following regular Team authors: Bradley, Briffa (the AR4 millennial reconstruction lead author), Overpeck, Caspar Ammann, David Schneider (of Steig et al 2009), Bradley as well as Otto-Bleisner (Ammann’s supervisor and conflicted NAS Panel member) and “JOPL-SI authors” who are various […]