It is time to stop quivering in our boots in pointless fear of the future and just roll up our sleeves and build it.
- Ray Pierrehumbert

Thursday, December 31, 2009

Relative Importance of CRU

Dr. Ken Green claims that "CRU, as I understand it, was the dominant source for information entering the IPCC reports". I found this assertion astonishing and implausible. I decided to come up with a quick test for this.

So I limit myself to chapter 3 of the AR4 WGI report, the one for which Jones is co-coordinating lead author, admittedly an important role. This is the atmospheric observations chapter, the one where CRU would be expected to be most influential.

Other than Jones, there is another co-ordinating author, (Trenberth, American), nine lead authors (one from the UK), by my count 66 coauthors, 10 of whom are from the UK, and three review editors (one from the UK). Of the dozen UK contributors out of the 80 participants from 16 countries, only Jones is currently at CRU.

The chapter cites about 825 papers. I checked the research staff of CRU against the bibliography looking only for first authorships to keep this project small. Of the 825 first authorships, four are P D Jones', one goes to Manola Brunet, four to Nathan Gillett, and two to Malcolm Haylock, for a total of 11 out of 825, a very respectable showing indeed, but hardly the be-all and end-all of climate science. Recall this is in the most CRU-favorable of 11 chapters, so we can conclude that CRU originates roughly between a tenth of a per cent to a per cent of the information in the WGI report.

For comparison here is Trenberth's group, the CAS at NCAR:

Dai seven, Deser six, Hurrell eleven, Madden one, D Schneider one, Trenberth 19, for a total of 45, or quadruple CRU's output just from the one section at NCAR.

While at it I scanned for authors with four or more first author publications in AR4 WGI chapter 3, and came up with:

R P Allan (5)
V R Barros
J R Christy
A Dai (7)
C Deser (6)
C K Folland (6)
N P Gillett
D Y Gong (5)
P Ya Groisman (6)
J W Hurrell (11)
P D Jones
R H Kripalini (5)
D E Parker
T C Peterson (6)
W J Randel (7)
J A Renwick (5)
I Simmonds
B J Soden
B M Sun
D W J Thompson (8)
K E Trenberth (19)
R S Vose
B Wang
X L Wang (5)
P J Webster
X Zhang (6)

of whom I had only heard of Christy, Jones, Parker, Soden, Trenberth and Webster. Chapter 3 is just not my thing.

I leave it to Dr Green or others to find a chapter where CRU is better represented but I doubt that there is one. Conclusion: evidently CRU is not "the dominant source for information entering the IPCC reports". It does appear that Trenberth's Climate Analysis Section group at NCAR carries a lot of weight in chapter 3, and if anyone is a candidate for dominance based on Chapter 3 it would be the NCAR/UCAR/Colorado bunch.


deepclimate said...

You should check Chapter 6 of AR4 - Paleoclimate (the other obvious CRU expertise). Keith Briffa is a lead author, and Tim Osborn a contributing author.

Also Chapter 9 - lead author Nathan Gillett (at CRU at time of IPCC writing, now at UVic). I didn't check the contributing authors.

CRU's standing is also seen in the many graduates who have gone on to great careers, such as Ben Santer, who said:

I obtained my Ph.D. at the Climatic Research Unit. I went to CRU in 1983 because it was - and remains - one of the world’s premier institutions for studying the nature and causes of climate change. During the course of my Ph.D., I was privileged to work together with exceptional scientists - with people like Tom Wigley, Phil Jones, Keith Briffa, and Sarah Raper.

Michael Tobis said...

I used the roster from their website which includes Gillett.

The question is not whether CRU is a fine and reputable scientific institution. I never questioned that. What is being alleged is that CRU dominates the IPCC. No CRU, no IPCC.

I found that excessive and that was the point of the exercise.

I am sure CRU comes out far ahead of U Texas, even if we get to claim Bob Dickinson as well as Camille Parmesan now.

deepclimate said...

I'd agree in the sense that no one institution could possibly dominate the IPCC. So Ken Green is definitely wrong on that one.

But CRU is definitely top in the UK, and arguably at or near the top in the world (say, in the top three or four). IIRC, you rated it quite a bit lower.

By the way, did you know Ken Green was behind the $10K offer from AEI for papers attacking the IPCC, especially modeling?

Michael Tobis said...

His version of that story is quite different. I don't want to take it up right now. I'm just trying to extract something coherent from those guys.

I'd like to hear from other Brits on how influential CRU is over there. I have certainly heard a lot more about Hadley than about CRU in my own career.

Gareth said...

East Anglia and climate go right back to Lamb. I can (dimly) remember that they were regarded as a real centre of climate expertise in the 70s - certainly paleoclimate. My guess is that they would "top" in the UK, and important globally, but certainly not dominant in the IPCC process.

Dano said...

So that one piece of vermicelli didn't stick to the wall. Ah, well. There's 574 more coming, surely.

BTW...sigh...decades ago now, when doing weather in Yurp the Brits had the best wx data and distribution system. The DWD was second and no one else's candle could even be seen.



Arthur said...

Since aside from the silly "CO2 fraction" claim this is the only slightly quantifiable point Green made in his comment in response to your post, I completely concur with looking into the actual numbers as you have here.

But another question for Dr. Green on this is - who could possibly have given you to understand that "CRU ... was the dominant source for information entering the IPCC reports" - have you actually looked at the IPCC reports to verify that, as Michael has here? Otherwise you must have obtained that information from somebody else. Who was it? Have you re-assessed your trust in that person, given that they were clearly lying?

deepclimate said...

I have certainly heard a lot more about Hadley than about CRU in my own career.

... possibly because Hadley is more prominent than UEA/CRU in your particular area, not necessarily in climate science in general.

But it doesn't really matter - the real issue is how Green could make the absurd assertion that CRU, or any other institution for that matter, is the "dominant" source of information.

You may have lowballed the numbers slightly by not looking at other chapters that play to CRU's strengths, but it's clear that Green's claim does not stand up to rudimentary scrutiny. So thanks for that.

Anna Haynes said...

2 points.

1. Dr. Haynes concurs with Dr. Smith that
a) we need to find out Dr. Green's sources of information on this ("who could possibly have given you to understand that "CRU ... was the dominant source for information entering the IPCC reports"?)
b) we need to find out from Dr. Green whether his credibility-of-sources mindmap is fixed, vs. whether it gets updated from feedback provided here and elsewhere.

2. For clarity, for passing readers, it would be good to maintain a list of: the (contrarian) assertions made here on In It by Dr. Green, the findings of Dr. Tobis in researching each assertion, and Dr. Green's response to Dr. Tobis's finding.
(Dr. Tobis, In It would be the optimal site for this, since it's mainly your project, but if you'd prefer I can set it up on Dr. Green's SourceWatch page. Let me know...)

Michael Tobis said...

Dr Haynes, if you pursue that strategy, I am not sure I would hang around here if I were Dr Green.

Time will tell, I suppose.

Arthur said...

On the "Dr" business - I have to say I love using it but I'm afraid it's with a slightly mocking tone because ever time I'm reminded of a chatty postdoc I got to know at Fermilab when I was in my relative youth (a 19-year-old undergrad on a summer jaunt).

Said postdoc had recently married, and his wife hadn't completed her PhD yet, but had already received her Masters. His joke was that at some point he suggested she should call him "Dr.", since he had his PhD. She was very happy to do so, as long as he in turn called her "Master" :)