Since the start of this blog on Feb 7, there have been nearly 27,000 hits. The biggest traffic was on Feb. 14, when there were nearly 4,000 hits (the link from the Wall Street Journal obviously caused this spike). Today is going to have the 2nd most traffic with over 2,500 hits in 20 hours […]
The MBH98 Corrigendum purported to explain the discrepancy of 35 series between the series listed in the original SI and the series actually used as follows: These series, all of which come from the International Tree Ring Data Bank (ITRDB), met all the tests used for screening of the ITRDB data used in Mann et […]
Gavin Schmidt and Caspar Amman of realclimate have written a "Dummies’ Guide" giving their take on the dispute: Due to popular demand, we have put together a ‘dummies guide’ which tries to describe what the actual issues are in the latest controversy, in language even our parents might understand.Link I’ll comment more on this later, […]
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.
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.
Climate Audit 
More Commentary #5: realclimate
Gavin Schmidt and Caspar Amman of realclimate have written a "Dummies’ Guide" giving their take on the dispute: Due to popular demand, we have put together a ‘dummies guide’ which tries to describe what the actual issues are in the latest controversy, in language even our parents might understand.Link I’ll comment more on this later, […]