Steve McIntyre has been playing a fun sort of “degrees of separation” game, identifying members of climate science’s “hockey team” based on coauthorship of paleoclimate papers and using their team membership to disparage their work. I’ve not found it to be a particularly useful or persuasive argument, and Tim Lambert has pointed out the inconsistency with which McIntyre applies it.
But I’ve always been fascinated with the whole Erdös/Kevin Bacon degrees of separation thing. So for a lunchtime exercise, I thought I’d see the shortest path I could find between McIntyre and Michael Mann, the two main characters of climate science’s long-running soap opera.
There’s only one rule in my game: No use of IPCC chapter co-authorship.*
Herewith, then, are the eight degrees of separation between Steve McIntyre and Mike Mann:
- In 2005, Steve McIntyre and Ross McKitrick published “Hockey sticks, principal components and spurious significance” in GRL
- McKitrick and Pat Michaels have worked together on several projects. We’ll go here with their 2004 “A test of corrections for extraneous signals in gridded surface temperature data.”
- In 2003, Michaels and John Christy were among the coauthors of a “Test for harmful collinearity among predictor variables used in modeling global temperature.”
- Last year, Christy and Roger Pielke Sr. wrote a critique of a paper in Science by Jim Hansen.
- In 2004, Pielke Sr. and Craig Allen were coauthors of a really interesting PNAS paper entitled “Cross-scale interactions, nonlinearities, and forecasting catastrophic events.” (In fact, rather than wasting your time on all this hockey stick war stuff, I suggest you go read this paper.)
- In 1999, Allen, Tom Swetnam and Julio Betancourt wrote “Applied Historical Ecology: Using the Past to Manage for the Future” in Ecological Applications. (Julio’s not technically necessary for this list, except that a) he’s one of the most interesting scientists I’ve had the pleasure to know, and b) it’s because of him that I knew enough about these fields to find a path through the literature.)
- It would be remarkable to not find a Swetnam-Malcolm Hughes link. I was sitting in Tom’s office a couple of summers ago interviewing him about tree rings and drought and he asked, “Are you going to talk to Malcolm? You must talk to Malcolm,” and took me upstairs and introduced us. I guess I’ll go with Hughes/Swetnam/Diaz – “Tree Rings and Climate: Sharpening the Focus,” published in EOS in 2004.
- Which brings us, of course, to Mann, Bradley and Hughes, co-authors in 1998 of “Global-Scale Temperature Patterns and Climate Forcing Over the Past Six Centuries”.
* I made up this rule ex post facto, because it made it too easy. Mann and Christy were co-authors of Chapter 2 in the last IPCC report, which short-circuits a whole bunch of interesting people. What can I say? It’s my game, I get to make up the rules.
update: In the comments I detail the discovery of a five-degree chain between M and M. For the first person to beat that (without using the IPCC chapter), I’ll buy a beverage of your choice the next time we happen to be in the same city at the same time.
Bonus points for anyone who can make a chain of any length linking William Connolley and Luboš Motl .