Friday, September 24, 2010

CliSci Survey - results documented

The results of the latest survey CLISCI by Dennis Bray and Hans von Storch among international climate scientists are now documented in GKSS-Report 2010/9: CliSci2008: A Survey of the Perspectives of Climate Scientists Concerning Climate Science and Climate Change. Results are also available for earlier similar surveys in 1996 and 2003 are documented in GKSS Report 2007/11.

Dennis Bray has published several minor analyses with these data on this weblog.


Marco said...

I think there is an error in the graph for Q 53 (p. 73). Just skimmed the report and thought it was an interesting question, but the table doesn't fit the graph...

Anonymous said...


A fascinating study.

On p. 21 of the PDF it appears that practically not a single scientist believed that climate science has not been influenced by politics, and a majority feel it has been heavily influenced. The next question shows something like a 50/50 split believing (not believing) that the field has remained 'value neutral', which I suppose is the same as just 'neutral'.

I've also looked at the questions about the GCM models. Considering results of all questions regarding the models, surely the best conclusion is that scientists generally don't have much sincere faith in them?

Alex Harvey
(Sydney, Australia)

Werner Krauss said...

I can hardly believe these numbers: 80% of the climate scientists (in this survey) are male, only 18% female? Wow, this is still stone age! Unbelievable. Climate is a real boy's toy, obviously. Are there any numbers on how many female IPCC lead authors, and how many peer reviewed articles according to gender?

MikeR said...

I would like to see some cross-tabs. Is it the same set of scientists every time on the extreme "left side" of the graphs?

corinna said...


I guess 80% male and 20% female scientists reflects pretty well the situation in climate science and related disciplines (without having performed any statistic, just according to subjective impression). The situation is certainly more balanced on PhD level, and getting less balanced on postdoc and senior scientist level.

But what I wonder about is why we hardly find any females commenting on Klimazwiebel (same for other climate blogs), at least according to my subjective impression.
I really wonder why, any idea?


Georg Hoffmann said...

The male/female number is completely not representative for my laboratory or for France in general both in climate science and in science in general.

A rough estimate gives a relation of about 60/40 for the LSCE (300 scientists/...) and in my working groupe (30 scientists/technicians/students) it's 30/70 male/female.

I also asked different persons if they ever received an invitation to participate to any of the polls organized by Hans and Dennis. Nobody ever heard about it. A bit astonishing since we are the largest climate research institute in France which is the second/third research nation in Europe.

Hans von Storch said...

Georg - we had only 5 respondants from France. Maybe it is related tot he sampling: "Three lists were employed in constructing the sample. List one included a list of authors, affiliations and email addresses drawn from climate journals with the 10 highest ISI impact ratings for the last 10 years. These are authors of climate related papers in peer reviewed climate related journals. The second list was the list of authors who contributed to Oreskes’ (2004) published conclusions concerning consensus in the climate change issue. A third list was drawn from readily available email lists on institute web sites (i.e. NCAR, MPI, AMS, etc.). The last one did not contain a French lab (sorry); maybe French authors were not that frequent among the first two lists? Could you ask your colleagues if they were invited by Oreskes, and to what extent they were authors in the highest ranked ISI papers?

Hans von Storch said...

Georg, maybe we could surveys specifically your lab? Would you help with that?

Werner Krauss said...

@corinna 6
This is my impression, too. Would be great to have some statistics. I have no idea how many women are among the (anonymous) comments on klimazwiebel. My impression is that it is pretty much a men's playground, but I am not sure.

@Georg 7
It would be interesting to see your numbers related to hierarchy. I heard it is also different in Norway and Sweden. Is this true? And what about IPCC, lead authors, reviewers etc.?
Maybe someone among our readers knows more....

Georg Hoffmann said...

Hans, we had more than 600 signatures in our open letter against against Allegre and Courtillot
and you had only 5 participants in France? That is really very few.

Highest ranked ISI papers? Thats Science and Nature, right? Yes we have many of them. My guess is that Jean Juzel alone has more than the entire MPI.

Yes I could send the info about your poll to our all address. Just send me the necessary informations.

Alex Harvey said...

Hi Hans,

No one responded to my question so I'm going to refocus it.

From this report I pick out some results (averages only):
12. How well do you think atmospheric models can deal with:

1 very bad - 7 very good
a.hydrodynamics -- 4.303279
b.radiation -- 4.673077
c.water vapor -- 3.838356
d.clouds -- 2.747253
e.precipitation -- 2.923497
f.convection -- 3.177596

13. How well do you think ocean models can deal with:

a.hydrodynamics -- 4.360335
b.heat transport -- 4.058496
c.oceanic convection -- 3.428969

14. How adequate is the ability to couple atmospheric and ocean models?


These are the aggregated opinions of serious specialists as far as I can see, and I don't understand how, given how average the opinions are on the _specifics_ of AOGCMs, how any scientist could be honestly hold the view that their predictions tell us anything about the future?

I mean, we all knew that the clouds were a problem. But the narrative has it that clouds are really the 'one last problem'. The one last hope for skeptics. But these results show that water vapour is only just behind. As is precipitation. The highest scoring is radiation at ~4.6.

These results surely support the idea that models have no future predictive value at all?


Hans von Storch said...

Dennis and I had discussed these results in The confidence did not rise in the course of time in our samples; in another survey, among scientists working on Baltic Sea issues, we found higher confidence. We do not really understand these results, apart of - possibly - of avoiding a 7 as answer, which lowers the overall mean a bit.

Ruth said...

Do you have plans to repeat the study to see whether opinions have changed since 2008? That would be very interesting.

eduardo said...

Dear Alex,

I have no experience in interpreting surveys, but I think It is always difficult to interpret the results of a survey of this type. My opinion on your questions is the following. First, you may be more surprised by the results than climate scientist would be, perhaps because you - and I think most of lay people- have been so far exposed to the mood of a portion of climatologist, mostly the ones that seek public coverage. But paraphrasing the words of Brian Hoskins, a well known expert on atmospheric dynamics, ' climate models are lousy, and we all know that'. In my interaction with other climatologist that are not modellers, I usually encounter levels of healthy scepticisms about climate models that may be surprising. Quite often I found myself defending climate models from critical comments by proxy experts, for instance.
However, this scepticism may be relative. For instance, when answering the questions 'how well can climate models can deal with radiation ' I would say that the answer depends on your own expectations about climate models. I would rather respond they are lousy because I would like them to be much better than they are ( I think this is a widely shared stance). But I would also respond that climate models are much better than nothing.
Actually, one does not need to search for too long to realize that climate models do not agree in many aspects and many aspects are not settled yet. If they agreed , they all would have the same climate sensitivity, for instance, and it is not a secret that the uncertainty in this aggregate measure of climate dynamics is large. But this does not mean that climate models are useless - they are getting better. I would recommend to read the corresponding chapter on climate model evaluation of the IPCC report - Chapter 8, Working Group 1. With some time and patience, you would perhaps discover new insights that are much more unlikely to be found in the technical summaries or in the summary for policy makers.

Alex Harvey said...

Dear Hans, Eduardo, #12, #14

Thank you for the link to the paper; I have read that now. Thank you Eduardo for the longer response. This is all interesting, although as both of you say, it's still hard to understand the results.

I draw attention to something else that's really puzzling me.

16. How would you rate the ability of global climate models to:
16a. reproduce temperature observations -- 4.942935 (mean)

16c. model temperature values for the next 10 years -- 4.15847 (mean)

16d. model temperature values for the next 50 years -- 3.711172 (mean) N.B. this seems very low, given some of the things the IPCC have said.

As I understand it, the belief that models can predict the right global temperature rise for, say, 50 years into the future depends critically on the ability of the models to get the sum of all climate feedbacks about right.

Now, if the models, say, got water vapor wrong, that would mean they'd get the water vapor feedbacks wrong too. If they get clouds wrong, they get cloud feedbacks wrong too. Is this reasoning valid?

So why would scientists believe that the models might get individual processes wrong but still get the SUM of all feedbacks about right? Surely, the sum of feedbacks is the hardest part of all. Only when every process is right would the sum of all feedbacks work out right. So why does the faith of so many scientists rise so much higher when asked "do they actually give the right answer w/r/t temperature?" Surely, this suggests brainwashing.

Also, wouldn't the study be better if there were explicit questions on feedbacks?

Note, I concede freely that I've read the criticisms against models made by Richard Lindzen, Garth Paltridge, Roy Spencer, Roger Pielke Sr., and others. If you feel something they've written may have mislead me w/r/t the significance of feedbacks then I apologise.

Best, Alex

ingno said...

It would be very interesting to read Dennis Bray's analysis concerning changes in beliefs about models and the state of climate science over time. Is there anything published on that?

Ingemar Nordin

eduardo said...


Dear Alex,

in my opinion one has to be consider one important aspect when interpreting the answer to question 16. It is clear by now that models produce different projections even when driven by the same scenario of GHG concentrations. Everyone is aware of it. So the answer about the skill of the models to predict the future climate must be related to the fact that all simulated a warming, although with a spread in its magnitude. When particular aspects of the feedbacks are then questioned in subsequent questions, the scientist would in his/her answer zero in particular deficiencies in the models.
So the confidence in the skill of the models is placed within the quite broad range of projections

Alex Harvey said...

Dear Eduardo & Hans,

I just found and posted this at Judith Curry's blog and it would be relevant to this discussion:

Lindzen & Choi 2010 (submitted to JGR), "On the observational determination of climate sensitivity and its implications"

To estimate climate sensitivity from observations, Lindzen and Choi [2009] used the deseasonalized fluctuations in sea surface temperatures (SSTs) and the concurrent responses in the top-of-atmosphere outgoing radiation from the ERBE satellite instrument. Distinct periods of warming and cooling in the SST were used to evaluate feedbacks. This work was subject to significant criticism by Trenberth et al. [2009], much of which was appropriate. The present paper is an expansion of the earlier paper in which the various criticisms are addressed and corrected. In this paper we supplement the ERBE data for 1985-1999 with data from CERES for 2000-2008. Our present analysis accounts for the 36 day precession period for the ERBE satellite in a more appropriate manner than in the earlier paper which simply used what may have been undue smoothing. The present analysis also distinguishes noise in the outgoing radiation as well as radiation changes that are forcing SST changes from those radiation changes that constitute feedbacks to changes in SST. Finally, a more reasonable approach to the zero-feedback flux is taken here. We argue that feedbacks are largely concentrated in the tropics and extend the effect of these feedbacks to the global climate. We again find that the outgoing radiation resulting from SST fluctuations exceeds the zero-feedback fluxes thus implying negative feedback. In contrast to this, the calculated outgoing radiation fluxes from 11 atmospheric GCMs forced by the observed SST are less than the zero-feedback fluxes consistent with the positive feedbacks that characterize these models. The observational analysis implies that the models are exaggerating climate sensitivity.