Real Climate has defended Steig against a plagiarism complaint from Hu McCulloch, covered by Pielke Jr here and Jeff Id here. Hu's original post is here and the most recent Climate Audit discussion here. Hu's complaint is here.

Note: Hu's email to the Steig coauthors is here. Steig was not the only recipient. All Steig authors were copied - Stieg, D Schneider, Rutherford, Mann, Comiso and Shindell.
Date: Sat, 28 Feb 2009 15:51:44 -0500
From: Hu McCulloch
Subject: Comment on serial correlation in Steig et al 2009

Dear Dr. Steig and co-authors,

FYI, I have recently posted a comment on your 2009 paper in Nature on Climate Audit, at While I was able to replicate or virtually replicate the 1957-2006 trends you report on p 460 for the three regions and the continent as a whole, the 95% Confidence Intervals you report appear to have taken no account of serial correlation in the regression errors. When this is done, the CI's are substantially wider than you report.

Any reactions, by comments there or by e-mail, would be welcome!
- Hu McCulloch

J. Huston McCulloch [email and other particulars]
Economics Dept.
Ohio State Univ.
Real Climate argues that Steig was in Antarctica when the McCulloch email was sent. Steig claimed the following:
Response: McCulloch's email, which provided no details but pointed me to his post, was sent while I was in the field in Antarctica, and would have received notification that I was in gone, and not receiving email for the next month.
Jeff Id sent a contemporary email to Steig and that is not the answer that he received. He received a message stating that Steig had limited email in Antarctica with a 30K file size max. (Hu's message was 6K and well within the 30K that Steig was receiving.)
I am in Antarctica until the middle of March. I will have email access via satellite, but text only is permitted, and 30 kB maximum file size. Please do not write except for essential matters. The email address is posted on my website at the University of Washington. Any issues pertaining to the lab should be directed to Andrew Schauer (contact information at - - ). Don Grayson (Archaeology) is acting Chair of the Quaternary Research Center while I'm away.
Best wishes,
Eric Steig
Hu received an out-of-office reply from Mann as follows:
Hu To:
Subject: Re: Comment on serial correlation in Steig et al 2009
Date: Sat, 28 Feb 2009 15:53:36 -0500 (EST)
From: (Michael Mann)
I will be away from my email through March 16, 2009.
Any email sent before then may remain unread and be discarded. If your message is important, you will need to resend after that date.
Notwithstanding this caveat, this does not preclude Mann processing his inbox shortly after March 16. An Real Climate reader grasps at this particular straw arguing that this exonerates all the Steig coauthors.

Before considering their defence of Steig, let me review their previous defence of Gavin the Mystery Man, originally discussed here and here. I had noticed curious properties in the Harry station in Antarctica, which were subsequently identified as resulting from the splice of two different stations. Based on information provided at Climate Audit, Gavin Schmidt spent his Sunday night determining that Harry had been spliced with Gill and notified the British Antarctic Survey (but not GISS) of the error. By the next morning, BAS had erased the incorrect series used in Steig et al, adding one further difficulty to replication of this study. Gavin said that a mystery scientist had "independently" discovered the problem and notified BAS.

Gavin stated:
It would have been nice had SM actually notified the holders of the data that there was a problem (he didn't, preferring to play games instead). If he hadn't left it for others to work out, he might even have got some credit
People will generally credit the person who tells them something. BAS were notified by people Sunday night who independently found the Gill/Harry mismatch. SM could have notified them but he didn't. My ethical position is that it is far better to fix errors that are found than play around thinking about cute names for follow-on blog posts. That might just be me though. - gavin]
I'm sure BAS are grateful that someone told them about the data mess up - it just didn't happen to be SM.
After being outed as his own "Mystery Man", Gavin stated:
i) discovering that Gill was mismatched with Harry was found independently by at least three people (SM, myself, and a poster on Climate Audit).
ii) the source of the confusion was indeed found and not given to me by anyone else, iii) we are all dependent on many things, including that SM had alluded to data problem at Harry - I don't see anywhere that I denied this. And BAS were notified by 'people' (plural) - not just by me. - gavin]
A Real Climate reader asked:
So let me get this straight, Gavin. You found the very same problem that SM alluded to, on the very same day he did, with no direct or indirect input from Climate Ausit? Is this correct?
[Response: Huh? Let's try again. He alluded to an unspecified problem, and I looked into it. I found the source of the problem with no further input from anyone. This isn't that complicated. - gavin]
I refer to the Gavin and the Mystery Man episode to demonstrate what Gavin's idea of discovering a problem "independently" meant. It meant reading comment threads at Climate Audit, where issues were being discussed openly, spending his Sunday evening trying to figure out where we were going and notifying the British Antarctic Survey the next morning before we woke up.

This also needs to be borne in mind when Real Climate authors claim to be unaware of posts at Climate Audit. Obviously this isn't the first such incident. Various changes were made at the Mann et al 2008 Supplementary Information responding to Climate Audit comments, without citing Climate Audit. On Feb 26, Hu McCulloch posted on Steig's failure to allow for serial correlation in their confidence interval calculations (even though they had said that they had done so.) The recent Steig corrigendum made precisely the same correction - without acknowledging McCulloch.

Real Climate acknowledged Hu's priority, but stated that Steig became aware of the error "independently".
This brings us to the recent claim by Hu McCulloch that a post on, detailing an error in Steig et al's paper in Nature on Antarctic temperature change, was not given due credit by Steig et al. when they published a Corrigendum earlier this month. In this case, McCulloch's comment on the paper were perfectly valid, but he chose to avoid the context of normal scientific exchange - instead posting his comments on - and then playing a game of 'gotcha' by claiming plagiarism when he wasn't cited.

McCulloch accuses Steig et al. of appropriating his 'finding' that Steig et al. did not account for autocorrelation when calculating the significance of trends. While the published version of the paper didn't include such a correction, it is obvious that the authors were aware of the need to do so, since in the text of the paper it is stated that this correction was made. The corrected calculations were done using well-known methods, the details of which are available in myriad statistics textbooks and journal articles. There can therefore be no claim on Dr. McCulloch's part of any originality either for the idea of making such a correction, nor for the methods for doing so, all of which were discussed in the original paper. Had Dr. McCulloch been the first person to make Steig et al. aware of the error in the paper, or had he written directly to Nature at any time prior to the submission of the Corrigendum, it would have been appropriate to acknowledge him and the authors would have been happy to do so. Lest there be any confusion about this, we note that, as discussed in the Corrigendum, the error has no impact on the main conclusions in the paper.
Real Climate's arguments here raise a couple of issues.

They concede that the "first person" to make Steig et al aware of the error deserves acknowledgement. However, they did not say who that "first person" was nor is another "first person" acknowledged in the post in question. OK, I'll bite. Who was the first person to make Steig et al aware of the error in the paper? Who is this mysterious person, unacknowledged in the Corrigendum?

Was it another "independent" discovery by the International Man of Mystery?

Update: In the first comment below, a reader observes that Steig said in a Real Climate comment:
In any case, I had already recognized the error in our paper before I heard anything about McCulloch.
This could be interpreted as meaning that Steig suddenly realized that they had goofed in their Nature paper and that there was no "first person". However, I don't think that it precludes the possibility of him being alerted to the problem by a non-McCulloch first person, perhaps even by the International Man Of Mystery. Steig could easily clarify this. If he suddenly realized the problem all by himself, I, for one, would be interested in knowing what led him to this sudden realization after the months of article preparation, discussion and peer review.