AAAS Letter

Alan Leshner, the CEO of the American Association for the Advancement of Science and Executive Publisher of Science, has written Rep. Barton objecting to the letters to Mann, Bradley and Hughes. The press release is here and the letter is online here. Leshner stated:

"There is nothing about the way it is proceeding in this particular case that ought to arouse Congressional concern about federally-funded climate science or climate science in general."

This comment seems to be insensitive to Mann’s statements to the Wall Street Journal that are "particular" to this case. In how many cases has a scientist been quoted on the front page of the Wall Street Journal proclaiming that he would not be "intimidated" into disclosing his algorithm? It’s hard to imagine a more provocative red flag to the people who ultimately funded the research, who are expected to rely on it and who doubtless innocently assumed that there were adequate methods in place in the climate research industry to ensure prompt archiving of whatever research data and metadata (including source code if necessary) to enable replication. Why wouldn’t Rep. Barton and others get concerned about this "particular case"? Many scientists try to argue that Mann has already provided adequate disclosure of data and methods. For example, Leshner also stated:

The papers in question have described the methodology as well as the findings, and additional information has been provided in on-line supplements to the papers (an increasingly common practice in the science community).

However, the argument that Mann has provided sufficient information to permit replication of his results flies in the face of Mann’s own explicit statement to the Wall Street Journal that he continued to withhold important aspects of his algorithm and would not give in to intimidation. How can Rep. Barton rely on Leshner’s assurances on the adequacy of the archiving in the face of Mann’s own explicit statements to the contrary to the Wall Street Journal? Leshner’s statement ignores the fact that Mann’s descriptions of his methodology and data were initially inaccurate in important particulars and have occasioned one Corrigendum to date. Some of the erroneous descriptions – for example, his tree ring principal components methods – were material and correct information was obtained or deduced only after much obfuscation.Leshner also ignores the fact that much of this archiving was provided only after repeated refusals by Mann and an intervention by Nature, resulting in the creation of a brand new Supplementary Information over 6 years after the original publication. As I’ve said elsewhere, Wahl and Ammann have not "exactly" replicated Mann’s results, contrary to their claims and the information currently provided is only sufficient to approximate Mann’s results. Leshner volunteered to assist the House Committee in their inquiry. I hope that the House Committee takes him up on this offer. One of the key aspects to quality control is journal peer review. I think that it would be highly instructive for the House Committee to learn from Leshner about policies at Science for peer review of paleoclimate articles, how Science ensures that research data and metadata for paleoclimate articles published in Science are archived, how Science ensures that research metadata (such as source code) is sufficient to permit replication, Science’s views on the policies of the American Economic Review requiring authors to archive source code and data as used as a condition of publication. I absolutely disagree with the presumption that the House Committee’s interest is anything other than legitimate. I think that Leshner is well-qualified to make an important contribution to clarifying quality control procedures in climate science research from a different point of view than any of the people that the House Committee has approached to date. I think that Leshner’s point of view is essential for clarifying the process and I hope that he gets the requested opportunity to explain these procedures to the House Committee.


  1. Manny
    Posted Jul 17, 2005 at 11:18 PM | Permalink

    FYI: Mann’s response to the Barton letter is posted at

  2. Jeff Norman
    Posted Jul 18, 2005 at 12:22 AM | Permalink

    Start quote:
    “… let me state that my research findings, which support the conclusion that the earth’s surface is warming, and that
    recent warming is due in large part to human influences, are consistent with the overwhelming scientific concensus on climate change.”
    End quote.

    I’m not getting the “my research findings… support the conclusion… that recent warming is due in large part to human influences”.

    I look forward to Steve’s interpretation of the rest.


  3. Mats Holmstràƒ⵭
    Posted Jul 18, 2005 at 11:49 AM | Permalink

    There is an article on the Barton letters in the Washington Post.

  4. Ted Hamilton
    Posted Jul 19, 2005 at 10:35 AM | Permalink

    It’s amazing how Mann and so many others cite the 2001 IPCC report’s suggestion of a “discernable” influence of human emissions on climate as an “overwhelming scientific consensus on climate change” where “recent warming is due in large part to human influences”. Even if the earth is warming they commit a basic logical fallacy, the classic hallmark of pseudo-science and superstition: that correllation is evidence of causation. Then there’s this gem he published on his own website: (

    “In the spirit of this article, let’s assume . . . that the “signal” of anthropogenic climate change has not yet emerged from the “noise” of natural variations (i.e., the above-cited “discernible human influence” had not been detected after all). Surely, then we wouldn’t need to worry about global warming, and the world could hold off with the Kyoto protocol? Unfortunately, that also doesn’t follow. The only thing that would follow in that case is that our data are not yet good enough to prove that anthropogenic climate change is already happening.”

    Without even considering that human emissions contribute perhaps

  5. TCO
    Posted Sep 20, 2005 at 10:09 PM | Permalink

    It’s ridiculous of a science org to defend the people who are hiding methods and attack the people who are trying to get them.

  6. Posted Mar 7, 2010 at 1:10 PM | Permalink, how do you do it?


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