In 2009, Steve McIntyre and I published a letter in Proceedings of the National Academy of Sciences arguing that a recent paleoclimate reconstruction by Mann et al. does not provide reliable evidence about climate change over the past millennium, because their data are inconsistent and their confidence intervals are wrong.
A BRIEF RETROSPECTIVE ON THE HOCKEY STICK:
In Spring 2014 I was invited to contribute a chapter to the Book Climate Change: The Facts, initially published by the Institute for Policy Analysis in Australia, and now by Stockade Books in the US. I was specifically asked if I would discuss the hockey stick episode, and it seemed an appropriate time to survey the story once again. Here is the result.
They wanted it fairly short, which meant it took much longer to write than if they'd asked for a long piece. Often I'd just be finishing the introduction and realize I'd hit the word limit. So naturally it doesn't provide an exhaustive treatment, but the reference list gives the reader plenty of additional leads.
PRESENTATION TO THE NATIONAL ACADEMY OF SCIENCES
This is our 2006 presentation to the NAS Panel investigating the hockey stick and paleoclimate reconstructions generally.
M&M CRITIQUE OVERVIEW
The most important scientific paper Steve and I put out was also, probably, the least read:
HOCKEY STICKS, PRINCIPLE COMPONENTS AND SPURIOUS SIGNIFICANCE
The key paper for cracking open the academic debate on the hockey stick was our 2005 GRL study:
After its publication two comments were submitted to GRL by Wahl/Ammann and Ritson, both of which were peer-reviewed and rejected (in part because they belabour points already resolved in our E&E paper). Two comments were also submitted by von Storch/Zorita and Huybers, and these were accepted (along with our replies). The von Storch/Zorita one is rather pointless, it merely presents a contrived case in which the PC distortion doesn’t matter. Our reply presented the reasons why their example was irrelevant to understanding the Mann data set, and along the way we present some pretty excruciating findings about how little temperature information is in the Mann data set. Huybers made a legitimate argument about how the RE score should be benchmarked, which prompted us to revise some calculations.
We also put out a little backgrounder to explain this exchange in more detail:
I have included on my pubs list the Materials Complaint we sent in to Nature. Though not a standard journal article, it was reviewed and upheld by the editors of Nature.
M&M 2003: THE PAPER THAT STARTED IT ALL
MARCOTT PAPER OP-ED:
I published an op-ed in the Financial Post on April 13 2013 reviewing the unraveling of the Marcott "Hockey Stick" graph.
WHAT IS THE HOCKEY STICK DEBATE ABOUT?
This essay carries the story up to early 2005 when our papers in GRL and E&E had just come out. That was the end of the technical issues, but the process carried on in the form of the expert panel of the US National Academy of Sciences, and the Wegman Committee reports.
NAS / WEGMAN Op-Eds: In 2006 Steve and I were asked to meet the National Academy of Science panel and make a presentation, whereas the Wegman Committee conducted its work without our input. We also sent a follow-up letter to the NAS Panel after the meetings to deal with some of the unresolved issues during the hearings. I summarized the final outcomes in these op-eds:
A well-received essay explaining the early history of the episode, and its implications, is
In winter 2005 we went to DC and spoke at the National Press Club about our work.
YAMAL DATA and the other hockey sticks: I published a column in the National Post on Friday October 2 2009, discussing Steve McIntyre's unraveling of the Yamal paleoclimate data and why it is important. This is of particular historical importance because it was part of the lead-up to Climategate.
CLIMATEGATE TV Special: In August 2010 Fox News did a special on Climategate, which can be viewed here. I appear in the segment beginning at the 20:57 mark.