Mann et al. [2000] listed 5 quality control criteria, which were said to have been applied in MBH98 for the inclusion of tree ring sites. These criteria were again referred to in the MBH Corrigendum in July 2004. In total, the information in the SI to MBH98 showed the use of 394 sites, either as […]
I will make here a very simple suggestion: if IPCC or others want to use “multiproxy” reconstructions of world temperature for policy purposes, stop using data ending in 1980 and bring the proxies up-to-date. I would appreciate comments on this note as I think that I will pursue the matter with policymakers.
A lot of people who are interested in the issue of the effect of bristlecone pines on MBH98 do not have access to Graybill and Idso [1993], the underlying reference, which we referred to in both MM05 articles and which I mentioned in this post . Here’s a pdf version , courtesy of the U.S. […]
This is a short discussion of the issues arising when a calculation step in a multi-step study cannot be replicated.
A new profile of Michael Mann appears in the March edition of Scientific American (on the grounds that you can never have too many profiles) Update: the author of the profile is David Appell. Isn’t it a small world? You’ll have to pay real money to see all of it, but here’s a rather revealing […]
The Corrigendum SI stated that: MBH98 made use of all nearly continuous monthly gridpoint surface temperature records (no single gap greater than 24 months, and no more than 10 years of total missing data. I checked these criteria against the temperature dataset archived at the Corrigendum SI and found that 242 out of 1082 gridcells […]
I have a considerable inventory of material on replication issues pertaining to MBH98, which does not really fit into academic journal formats. I’ll probably do about 25 of these notes, which may interest a few people and will illustrate the obstacles to replicating MBH98 without a close examination of source code. I’ll start first with […]
I’ve updated to the Categories on the right bar to distinguish comments on MBH98, Moberg [2005], News and Commentary, Post-1980 Proxies etc. , which cover the main current themes on this blog.
Further to the lengthy article by Antionio Regalado on Feb. 14, 2005, the Wall Street Journal on Feb. 18, 2005 had an editorial referring to the present matter: Mr. Mann’s chart was both a scientific and political sensation. It contradicted a body of scientific work suggesting a warm period early in the second millennium, followed […]
Melanie Phillips says: so many people have made huge reputations from all this rubbish. What an astonishing scientific scandal this is, and growing by the day. Link
Climate Audit 
Sci-AM: Confirming the importance of MBH 99
A new profile of Michael Mann appears in the March edition of Scientific American (on the grounds that you can never have too many profiles) Update: the author of the profile is David Appell. Isn’t it a small world? You’ll have to pay real money to see all of it, but here’s a rather revealing […]