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« Bob's book | Main | Hockey Stick Illusion denial »

St Andrews debate

John Shade, of Climate Lessons blog, sends this report on my debate at St Andrews.

On a wet and windy day, off to St Andrews, where the School of Geography and Geosciences was holding a discussion meeting on climate as one of its World Series Seminars. Speakers: Andrew Montford, and Tom Crowley, a recently retired professor of paleoclimatology. Chaired by Dr Robert Wilson, who said that he was a great believer in discussion where there was discord, and that there was discord in the climate world. He gave Andrew a pleasant and welcoming introduction, noting that he had been quoted in one newspaper report as believing that CO2, all things being equal, will make things warmer.

Before Andrew’s presentation Dr Wilson, tried a quick straw poll of the roughly 60 or 70 people present (my guess, and I also guess that most were undergraduate or graduate students). He asked who believed there had been global warming, and that man had contributed to it – which was a disappointing note since the crucial areas of debate are not on those beliefs, but on the magnitude and other details of climate change over the next 50 to 100 years or so. Then he asked who saw themselves as sceptical. I raised my hand both times, albeit a bit hesitantly the first time. Not many raised their hands the second time – a ‘few’ was how Robert described it.

Andrew’s topic was ‘The Global Warming Debate After Climategate’. He recapped the basic details of Climategate, and of the serious allegations that were raised about climate scientists as a result. He talked through each of the three enquiries and demonstrated that they were all inadequate and had failed to directly address the allegations, thereby earning Andrew’s epithet of ‘whitewashes’. He said people have noticed that these were not serious attempts to get at the truth, and this destroyed trust. He returned again to this theme of lost or damaged trust, noting the IPCC standing by the hockey stick plot even when it knew it was wrong, and of the sleight of graph involved in splicing instrumental readings on to a time series plots of reconstructed temperatures when the reconstructed values turned sharply down instead of up. He noted the curious amount, and direction, of adjustments to temperature records – always to make the present warmer and the past cooler. He did not know whether or not the adjustments were justified, but merely noted that they made him uneasy.

He maintained that trust needs to be rebuilt in climatology, noting that he did not believe all climatologists were corrupt, but that there were some bad eggs in there. He welcomed the willingness of some to discuss issues in a civilised way, and said that both sides need to work very hard to be nice to each other. As more recent development, he noted the facile claim of accelerating warming by doing successive straight-line fits to sections of the temperature record, showing the illustration (due to Paul Matthews) of how this worked in a similar way when done to a simple sine wave. Why did some talk of acceleration based on this?, he asked and noted it as an example of the sort of thing that has to stop. He recalled being told by one climatologist who had posted a 5* review of HSI on Amazon, that he had done so anonymously to avoid repercussions. Turning to recent global temperature reports, he noted that the lack of warming was catching the attention of such as Phil Jones, and of people he had met in the Met Office recently. He noted that climate models had not been working well at the global level, and at the regional level were even worse, and showed a plot contrasting predictions made through the IPCC in the year 2000 diverging up and away from the actuals which were fluctuating about an approximately horizontal trend (chart due to Lucia on the Blackboard blog). He asked if these such models were fit tools for government policy, and said he though not. In winding up, he reiterated that trust has been destroyed, and that the phrase ‘Trust Me, I’m a Scientist’ doesn’t hold water anymore.

Recently retired, Professor Tom Crowley was the other speaker, and his subject was ‘Progress in Understanding Climate of the Last Millenium’. He started by saying he was feeling as bit wrong-footed by Andrew’s talk being different from what he had expected, an observation he was to make again a couple of other times. I think he had been expecting Andrew to be talking mostly about the hockey stick plot.

His introductory slide was of a roadside sign for the ‘Chaos Café’, and this stayed up for quite a while until he got into his main materials. Before then, he invited us to be concerned about the recent high temperatures being reported in the States, with averages in March being 8.6F above normal. He said this was a colossal warming.

He spoke very highly of the IPCC reports, and returned several times to this later. He had used the 1st and 2nd assessment reports as core material for classes he had taught back then on climate. He said virtually nobody has disputed what they have said, and noted that some 50,000 comments on drafts have been responded to. He noted that government representatives had voted sentence by sentence on the Summary Reports.

He showed showed a new plot (not yet published) which had the hockey stick shape using tree rings from 1801 to 1984, constructed using simple averaging of the reconstructions used. He noted that while individual records may be flawed, this averaging helped produce a more reliable result. He talked to some of the major features on the earlier part of the plot, generally referring to volcanic eruptions as likely causes, and then later, from about 1900 onwards by aerosols due to industrial pollution. He showed a plot of sulphate depositions found in Greenland ice – in the flight path of the prevailing winds from the US. These showed a drop in the 1930s which he associated with the Depression of those years, a drop which was not recovered from on the plot until 1954, roughly following a similar performance in the Dow Jones Index. The Clean Air Act in the 1970s led to improvements, but before that there was a surge of readings from abour 30ppb to 200ppb at their peak. This he described as great wads of sulphur, having earlier asked any gardeners present if they would deliberately pack sulphuric acid powder around the base of their valued plants.

He showed another plot with global temperatures (mostly as per Hadcrut means as I recall) , with CO2 growth almost perfectly superimposed from about 1800 to the present, and once again invited our concern. A further, yet to published plot due to Levitus, showed substantial heating in the upper ocean. All this he described as rock solid.

He said the IPCC view was that doubling of CO2 would lead to global mean temperatures rises of 2 to 3C in 30 years from now, and these would be the highest in a very long time (I cannot decipher my notes on the actual time period). He repeated the assurance of the IPCC about continued warming, and his confidence in the IPCC.

My notes are a bit scrappy for the question and answer session which followed, and which was ably handled by Dr Wilson, since I was from time to time formulating questions or comments of my own.

An early question concerned differences in variability displayed on different sections of plots shown by Tom – described by the questioner as ‘huge differences in uncertainty’. Another questioner argued that a detailed re-analysis of tree-ring data was called for in general. The question of how much longer a period without warming would cause people to say something was wrong with the models and/or the claims of a warming threat. Tom suggested that if warming not resumed by 2020, that would cause concern. A questioner noted that there were massive leaps being made from projected temperature rises to talk about climate impact in general – impacts that have not been remotely justified e.g. talk of floods and droughts and famines and so on.

The excess winter deaths in Scotland were raised to illustrate more harm from cooling than warming here. An audience member claimed that climate scientists were intrinsically sceptical – that was part of science, and that it was very misleading to think of a simple divide between climate sceptics and true believers. The same person also praised peer review as one of the strengths of climate science, and urged sceptics to get engaged and try to get published. There was some mention of Arctic ice thinning, the high variability Arctic sea ice and thickness so that even a dramatic summer melt at the pole would not be unprecedented even in the last 100 years, of sub-tropical drought forecasts and poor guidance to the Australian government about permanent drought down there (with desalination plants build not long before floods due to very heavy rains appeared and the plants were mothballed).

The Clausius-Clapeyron relationship was raised to note airborne water vapour would increase with rising surface temperatures, and that led to questions about negative feedbacks involving clouds tending to counter such rises). Someone noted that economic models also needed a lot more examination. What should be done? Bets were bandied about about temperature rises in the near future. It was noted that the self-interest of developing states such as India and China may not coincide with greenhouse gas reduction. Tom said it would be in the self-interest of the States to reduce dependence on imported oil, and that in general people should try to do what benefits their own country. A questioner had asked if it seemed that global governance was the only way to go if greenhouse gas reductions were to be addressed.

The climategate scandal was mentioned, and Tom said that it had nto affected the science, and that anyway, scientists were human beings. He felt that if there was 1 dodgy paper out of 100, that one would be blown up out of all proportion by the blogosphere. A suggestion of massive oil funding by an audience member was greeted with derision by the ‘sceptics’ present, and when Tom started to talk of Exxon in particular, there was a remark from the audience to the effect that going down that line would make ‘us’ no better than the sceptics, and that produced an approving murmur in the audience and the topic was dropped. A questioner asked what would it take to change a sceptic’s mind – for example, if they saw there was only a 1 in 20 chance that the projections were right about CO2, what would they do? The case of the resigning editor and reviewers at the Remote Sensing journal was raised, by Andrew I think, as an example of something wrong with the science – if a weak paper gets through, why not simply print a rebuttal, why resign, and why, in particular, apologise to Trenberth – a man not in the speciality in question. Andrew raised the question as to whether peer review was adequate in climate science, and the politicised situation. I think there was consensus that peer review is not perfect and that moves to open peer review were a good development. Several people pointed out that both sides of the debate had been politicised.

The discussion had been, as they say, wide-ranging and often lively. But always temperate, and my impression was that everyone would have felt they had some opportunity to be heard. Dr Wilson helped keep an even keel, and invited us all to another room nearby for refreshments and further discussion. All in all, a worthwhile event with some good communication of perspectives and bits and pieces of ‘facts’. Would that such events, in such an open and courteous atmosphere, could be held far and wide. They weren’t in the past, and we were told by some that the debate was over. I think for most of us, it has in fact scarcely begun. Back to the car park to find some of the West Sands had been spread there by the wind to give a slightly Saharan look to the place."

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Reader Comments (365)

@ Rob Wilson aka The Yummy Troll

I look forward to your posts and appreciate your time to discuss the science with a wider audience. However, it is your science opinions including your perspective on how the science should be interpreted by your peers and the public at large where my interests lie; less so on your humor.

I agree that there is more chaff than wheat in this thread (for example), but that is no reason to deny the majority of readers the occasional kernel of truth.

Apr 30, 2012 at 8:13 PM | Unregistered Commenternvw

Skiphill, cue for Rob to say he doesn't do politics. We could all have a nice cosy discussion on paleo, on whether temperature over the year is the maojor determinant of ring thickness when we have no clue as to rainfall, early spring, sheep droppings or any of the factors of which he must be far more aware than I. We could all decide on what data was lacking, where we needed to fund another expedition, whether there was a close-enough Starbucks and so on. The problem is that paleo is being used to push an agenda of urgency. Not by Rob, I'm sure. But sceptics here are concerned with the timetable of the politicians. If it were only science, we could leave science to sort itself out, as it will in due course.

Apr 30, 2012 at 8:24 PM | Unregistered CommenterRhoda

@Rob Wilson, I'm sure that alot of people here would take you more seriously if you actually said that what Mann did with his "Hocky Stick" reconstructions was wrong both in terms of the data selection methods and the statistical analysis.

You might also add that Phil Jones was not correct to refuse to release data when a legitimate enquiry was made.

State this in a meanstream journal and not just on a blog like this, then I will take you seriously and trust that others here will do so as well.

Apr 30, 2012 at 8:47 PM | Unregistered CommenterDon Keiller

Didn't Rob Wilson decline to correct a mistake in identifying Yamal as Polar Urals in a paper? That is what you will find at climateaudit. Didn't think it was a good idea, apparently.

Apr 30, 2012 at 8:51 PM | Unregistered CommenterRhoda

One last comment w.r.t. Mann et al. (1998/99).
Is this analysis flawed? No, not really - it was one of the first attempts at trying to do a rather complicated job

Really? Honestly?

Firstly, the statistics are not just a little bit dodgy. They are just plain wrong, and not in a good way. The techniques being applied (e.g. multivariate statistics, PCA) are over 100 years old and date back to Pearson. There is nothing new or innovative here, other than the numerous errors.

And what is more, the statistics are applied very, very poorly. The primary reason it took so long to find the errors (I think I counted over ten at my last attempt) was not because the study was difficult or clever but because the poor quality analysis was hidden behind flowery and inaccurate writing.

Now, I don't begrudge the paper being written. Dozens of jobbing researchers in my field chuck PCA and similar approaches to data sets. They get a paper out of it, usually of little worth or merit, but the analysis is usually okay. But these papers are usually (1) written considerably more competently than MBH98/99 and (2) are quietly forgotten about and do not get promoted as the pinnacle of a research field.

But even despite that, the thing that I find most astonishing is that now we know how incompetent Mann is, that he is still so strongly defended by those in the climate science community. I can understand environmental activists and advocates supporting his work - they don't understand enough about science (or don't care enough about science) to know it is wrong. But why are scientists still shrugging their shoulders and saying it isn't that bad? The work was dire, end of story. Anyone unable to admit that either really doesn't understand what is going on (and I don't believe this is the case for Rob at all) or is not being entirely objective about this.

Incidentally, looking at Jason Smerdon's latest preprint I see Mann's team is still continuing what they are good at: making numerous serious errors in their paper and then refusing to admit to them. It would be an understatement to say Jason's frustration is palpable in the text.

I wonder if Michael Mann attended the awarding of the Arthur Holmes medal to Vincent Courtillot in Vienna?

Apr 30, 2012 at 9:30 PM | Unregistered CommenterSpence_UK


Paul, if we cannot agree on the timing or scale of previous episodes of warming how can we know what forcings were acting then which are not acting now? What is the definitive temperature record which we can use for calibration? Does it have the global MWP, for example, or not?

Well, of course there is no definitive temperature record. IPCC AR4 now has a spaghetti plot of various multiproxy reconstructions (Fig 6.10) - these are just for the northern hemisphere and they do show an MWP and LIA. One interesting aspect of this field is how we can start to hone in on the most likely reconstruction using a combination of proxies and models. But there are uncertainties in both, so it is a messy process. However, there is no doubt that we've moved on a lot since we only had the Mann reconstruction, which had very little variability compared with subsequent efforts.


My understanding (correct me when I'm wrong) is that the Met Office model contains the following forcings:

Solar variability (a tiny effect)
Volcanic erruptions (a short-term downward push on temps)

Not sure - I think you'll find that the Met Office uses different models, with different forcings. They may also include orbital and aerosol influences for example

What previous warming events do the models explain? And what forcings do the models use to explain them?

I think orbital forcing can explain the long downward trend since the Holocene optimum. And solar and volcanics help explain the LIA. The models have more of a problem with internal variability (this is likely related to very complex dynamics of ocean-atmosphere coupling), so to the extent to which actual warming and cooling events arise from internal variability, the models won't reproduce them - although they can be set up to simulate similar events with similar amplitudes. The ENSO cycle is an example - the models can reproduce ENSO type events, but they won't happen at the same time in the models as they happened in the real world. That's where proxies come in.

Hope that helps - but its probably better to ask the same question of Richard if he comes back on another thread. I think this one is experiencing its dying spasms !

Best wishes


May 1, 2012 at 12:30 AM | Unregistered CommenterPaul Butler


from your link - CL4.8/BG2.22
Climate Change: Carbon Cycle, Mortality, Growth, and Shift of Forests

this may have been covered above but, what does this mean "authors' preferences" & "Quality of works is definitely not discriminated by being selected for an oral or poster session."


Climate Change: Carbon Cycle, Mortality, Growth, and Shift of Forests

Convener: F. D'Aprile
Co-Conveners: N. Tapper , D. Dunkerley

Convener Login

Oral Programme / Fri, 27 Apr, 15:30–17:15 / Room 19
Poster Programme / Attendance Fri, 27 Apr, 10:30–12:00 / Hall Z

Add this Session to your Personal Programme

The session will focus on the effects driven by climate change on forest carbon cycle, health and mortality, growth and dynamics of forest species from the local to the regional scale, or wider; forest health would include response to forest diseases. Research related to the main subjects of the session will be considered.
Public Information: Please note that oral and poster presentations are mainly selected on the basis of authors' preferences within the constraint of time availability for presentation and complementarity with other subjects. Quality of works is definitely not discriminated by being selected for an oral or poster session.

tree line history/sdudy not part of the discussion?

May 1, 2012 at 1:10 AM | Unregistered Commenterdougieh

Here's an abstract from icer's link. Hadley + Met Office hyping their stunning seasonal to decadal prediction capabilities:

Seasonal and decadal predictions toward climate services.
C. Buontempo, C. Hewitt, and A. Maidens
Met Office Hadley Centre, Exeter, UK

While societies have flourished or collapsed depending on their ability to adapt to changes in climate, it is only recently that science and technology have been able to provide useful insights into future climate. Seasonal to decadal (S2D) forecasts hold the potential to be of great value to a wide range of decision-making, where outcomes are heavily influenced by climate variability. Recent advances in our understanding and ability to forecast climate variability and climate change have brought us to the point where skilful predictions are beginning to be routinely made. Access to credible forecast data, supported by informed guidance from the science community, could lead to significant advances in society’s ability to effectively prepare for and manage climate-related risks. This new ability will effectively represent the core of climate service offers in the coming years. A number of initiatives such as Global Framework for Climate Service or the International Conference on Climate Service have recently been launched to coordinate climate services activities internationally. The European Union acknowledged this new development in the research agenda and last summer opened a call on seasonal and decadal predictions toward climate services. While it is not yet know which projects will be funded they will all have to improve the underpinning capability of the models and at the same time develop an effective mechanisms to make the prediction relevant and usable by decision makers.

We will discuss the GloSea4 seasonal forecasting system, giving a brief description of the system and some of the products we supply to end-users as part of our climate services and our seamless approach to forecasting across varying timescales. The basic approach of a recently submitted proposal to the EC to exploit these emerging prediction capabilities and, more importantly, to engage with potential users of such predictions will also be presented.

Recent Met Office prediction:

Met Office 3-month Outlook
Period: April – June 2012 Issue date: 23.03.12
The forecast presented here is for April and the average of the April-May-June period for the United Kingdom as a whole.This forecast is based on information from observations, several numerical models and expert judgement.


The forecast for average UK rainfall slightly favours drier-than-average conditions for April-May-June as a whole, and also slightly favours April being the driest of the 3 months.
With this forecast, the water resources situation in southern, eastern and central England is likely to deteriorate further during the April-May-June period. The probability that UK precipitation for April-May-June will fall into the driest of our five categories is 20-25% whilst the probability that it will fall into the wettest of our five categories is 10-15% (the 1971-2000 climatological probability for each of these categories is 20%).

What actually happened:

BBC News
30 April 2012 Last updated at 17:52

April is the wettest April for 100 years

Aerial video shows Somerset floods

Man dies as floods create havoc

Somerset’s rivers on flood alert

Badminton Horse Trials cancelled

This has been the wettest April in the UK in over a century, with some areas seeing three times their usual average, figures from the Met Office show.

(HT to Adrian Kerton at WUWT who originally posted the above information)

May 1, 2012 at 2:14 AM | Unregistered CommenterBilly Liar

Nice conclusion by Rob Wilson, although several points to disagree with, and haggle about as well. :)

If you go to wattsupwiththat, you'll see that Willis Eschenbach pulled a similar trick on readers too. I do think that scientists get treated like celebrities on websites and they can't sometimes do 'normal' things - like making goofy forum mistakes.

blog chat is not science per se. It produces heat and, to paraphrase Hitchens, heat is the best way of producing lots of light.

May 1, 2012 at 6:51 AM | Unregistered CommenterShub

Apr 29, 2012 at 5:41 PM | Cassio

Before considering "impacts of warming" surely we must discuss what other aspects of weather and climate may be - or are being - influenced by man, and the evidence for that ? Or do you consider that AGW itself will produce these other changes in climate ?

Thanks for the question, sorry I missed it earlier.

I agree with you that it is important to discuss all aspects of weather and climate that may be influenced by man. Yes I consider that AGW can involve changes in other variables such as precipitation, but it's not the only way in which we are influencing climate - land cover change is also important, as discussed (for example) in this paper by Roger Pielke Snr, myself and others. We need to understand the whole lot!

Incidentally it seems extraordinary that the Met Office employs researchers like Dr Betts, whose areas of interest and expertise are so far removed from actually forecasting the weather

For reference, my university education was as follows:

BSc Physics (Bristol)
MSc Meteorology and Applied Climatology (Birmingham)
PhD Meteorology (Reading), thesis title: "Modelling the effects of the vegetated land surface on climate and climate change".

The MSc included practical forecasting in the course and in the university's own weather office.

When I started at the Met Office I took the 4-month Scientific Officer's course, which again included practical forecasting as well as theory.

So yes I do have formal training in meteorology! My PhD got me into vegetation modelling, as I was looking at the interactions between vegetation and climate. Most of my publications have been in that field.

This is why I've been able to work in 2 different roles in IPCC.

In AR4 I was in Working Group 1 ("The Physical Science Basis") on the radiative forcing chapter, with the particular remit of assessing the impact of anthropogenic changes to the land surface (deforestation etc) on radiative forcing - mainly via surface albedo change.

In AR5 I have moved to Working Group 2 ("Impacts, Adaptation and Vulnerability"), working on the chapter on terrestrial ecosystems. As well as having a track record relevant to that, it is also useful to have someone like myself who also knows about climate modelling (WG1 territory) - unfortunately in AR4 the different Working Groups were not particularly joined-up and authors, in one working drop didn't always know much about the details of the work of the other working group. This led to inconsistencies and differences in approach. Hopefully I (and some others) are helping to bridge that gap.



May 1, 2012 at 11:42 PM | Registered CommenterRichard Betts

Richard Betts,

I am interested to know if your AR5 working group is considering beneficial aspects of warming as well as potential adverse effects. For instance, off the top of my head: reduced winter deaths in cold climates; reduced need for heating of buildings in cool temperate and sub-arctic areas (hence less use of fossil fuels, surely a negative feedback on global warming, if the CO2 meme is accepted); and enhanced agricultural production in countries like Canada and Russia. I cannot see any logical rationale for not considering such potential benefits, unless the IPCC charter precludes it, which is its own indictment.

Thanks Richard, hope you can find the time to reply. If you miss this post I shall repost it later in the UKMO thread.

May 2, 2012 at 1:44 AM | Unregistered CommenterChris M

Footnote - Steve McIntyre to Jeff Condon The Air Vent. Comment 4

May 7, 2012 at 10:01 PM | Registered CommenterPharos

Steve Mcintyre (requesting data)

"I’ve asked the various authors to archive the data or provide it to me, but they haven’t acknowledged my requests. I asked Rob Wilson to speak up on my behalf but he asked that I not involve him"

Jul 26, 2012 at 9:55 AM | Unregistered CommenterBarry Woods

When the going gets hot in the kitchen, Rob Wilson gets going.

Jul 26, 2012 at 10:05 AM | Unregistered Commenterkim

Dear Dr Betts,

Prompted by new posts on this thread I discovered your post of May 1, 2012 at 11:42 PM, in response to mine. My apologies for having overlooked it because I omitted to opt for follow-up comments.

Your account of your background and current activities is interesting, and I have no doubt of your impressive credentials. But that was not my concern. What I hope to understand is why the Met Office should employ you and others to study vegetation modelling. Do you study how changes in vegetation (e,g, loss of tree cover) might affect the weather or climate, or are you solely concerned - as your reply appears to imply - with the possible effects on vegetation of changes in the weather or climate ?

Jul 26, 2012 at 11:32 AM | Unregistered CommenterCassio

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