There's a new paper out in Nature Climate Change that caught the eye of Anthony Watts (archived here). I bet he's relieved to have something else to talk about, instead of the demise of global warming (which is as alive as ever, unfortunately).
Update: There's now a published comment to the Hollin and Pearce paper, which is discussed here: The IPCC climate message is clear based on the evidence: The fundamental flaws of Hollin & Pearce
The paper is both timely and out of date. Timely because it relates to "seepage" - which was the subject of a recent paper discussed here a short while ago. Timely also because it's all about the so-called "hiatus", with the authors even claiming (in their
The paper is by one of the UK "deniophiles" called Warren Pearce, together with a post-doc at his university called G. J. S. (Gregory) Hollin, who looks to be studying autism (updated dead link Oct 15). This unlikely pair somehow got their unlikely paper accepted and published in Nature Climate Change. I don't know what the editors were thinking.
I had a look at the paper, and it seemed very simplistic and without much substance. I'll do my best to describe it. The authors decided off the bat that scientific communication is all about uncertainty and meaning. They wrote:
In this paper, we assess the relationship between two fundamentals of science communication: uncertainty and meaning
Not the meaning of uncertainty - that can be calculated. I think they were talking about the meaning of science and conveying that meaning to a scientifically illiterate public. Or more particularly, to one scientifically illiterate journalist, called David Rose.
Gregory and Warren focused on the press conference that was held when the IPCC Working Group 1 report was released in late September 2013. The paper isn't very long. It has a few very basic diagrams, simple enough so that maybe even David Rose could understand them if he tried. There was quite a bit of waffle up front - or what seemed like waffle to me. The first two pages were basically a long lead in to the argument that David Rose's "ill-posed question" wasn't really ill-posed at all. In fact it was ill-posed and Michel Jarraud, the Secretary-General of the World Meteorological Organization (WMO), explained why. I figure that neither G. J. S. Hollin or Warren Pearce understood what makes a scientific question ill-posed. They certainly didn't write about this in the manner in which it was explained. David's loaded question was of the type "have you stopped beating your wife":
"How much longer will the so-called pause or hiatus have to continue before you would begin to reflect that there is something fundamentally wrong with the models?''
If you want to see it on video - click here (at 1h 3 min 48 sec )
What Thomas Stocker replied was:
These climate models have shown remarkable agreement with the longer term trends that are observed, and that I have shown over the last 100 years. And this gives us confidence , together with other changes that are simulated in these models and at the same time observed in the climate system. Like for example the reduction in ice or the uptake of heat in the ocean. These are the kind of variables on which we build confidence in these models.
There is an entire chapter in our assessment that concludes that models have improved in their performance, that they compare better in many variables. But of course, such a comparison is much more comprehensive than just looking at the last ten years. I should also say that it very much depends which of the last ten or fifteen years you would actually pick for a model comparison. And we are very clear in our report that it is inappropriate to compare a short term period of observations with model performance.
David Rose then repeated his question about the "hiatus":
So with respect, you've not answered my first question. How much longer would the hiatus have to continue. Never mind what the start date is, the start date is when it is. How much longer would it have to continue before it would cause you to consider that the models may be flawed?Thomas Stocker patiently responded:
I may not be able to give you a number. Certainly if we experienced for the next twenty years constant temperature, I would say, with great confidence, that this is not an option given the emissions of greenhouse gases that we measure every year at levels unprecedented, record emissions. And the relationship between warming and the emissions of greenhouse gases is a very robust one. But it is clear, there are phases of natural variability. For example, if we have a large volcanic eruption next year or a couple of years from here, then we would expect, of course, cooling.
Michel Jarraud then took over and said: 1:08:28
Yes, Maybe I would like to deal with your question in a different way. From a scientific point of view, your question is what we would call an ill-posed question. And it is based on somewhat a misunderstanding of how the model works. Let me give you a few steps to explain what I mean.
In this room, the air molecules keep on bumping into each other. This is what we call Brownian movement. This movement is essentially unpredictable. However, it doesn't mean that because of that we cannot predict what the weather will be over the next few hours or the next few days. And actually it's done with remarkable accuracy.
Now let's go one step further. It is impossible and it will always be impossible to predict one year in advance whether there will be a thunderstorm in a given place. However, it is possible to predict trends. Predict evolution of anomalies over a larger scale.
Let's go one step further. It's not because we cannot predict these things one year in advance that we cannot predict the evolution of the climate, which is based on the interaction between a number of elements, like the ocean, like the atmosphere, like the cryosphere, like the land surface. And the model is, as you would say in the UK, the proof of the pudding is to a large extent in the eating of the pudding. And these models are becoming more and more remarkable at predicting the large scale trend. The longer term trends.
But, back to my ill-posed question, it would be wrong to judge a model on the ability to predict some individual event in this natural - oh, not only natural, in this variability. So therefore you should distinguish the ability to predict individual temperatures ten years in advance, from the ability to predict trends over twenty or thirty year periods.
Back to your question. It has been a recommendation from the World Meteorological Organisation, when looking at the climate issue, it is important to look at long trends. And indeed I think, Chairman, you mentioned that. The consensus is that one of the best time scale to look at that is thirty years time scale.
Now there's one point to make clear. While there was much mirth among climate bloggers that David Rose was told his question was "ill-posed", that wasn't presented as an insult. We all just took great delight because of David Rose's appalling climate articles (see below). However, the term has a special meaning, and Michel Jarraud made that clear by saying "From a scientific point of view, your question is what we would call an ill-posed question". What it means is that if you want a meaningful answer from science, you need to frame your question in such a way that there will be minimal ambiguity in the answer. In mathematics it means that a problem has not been stated in such a way that there is an unambiguous and unique solution (refer Hadamard's definition).
From my perspective, the question was pretty poor because it was clearly a loaded denialist question. If David had been interested in the subject of climate models, he would have known that no model is perfect. All have flaws - or more properly, all have limitations. The important thing is being aware of these limitations, and to test them to make sure there is nothing unexpectedly wrong with them. As it turns out, the models have certain forcings built in. At the time they are finalised these forcings are what is known eg solar radiation - and for the future, what is assumed. Solar radiation in the future isn't known, so it has to be estimated. The CMIP5 models had forcings based on observations up until around 2006 and after that the forcings were estimates. So in regard to the forcings there are two possible sources of error. One is that the observations might be inaccurate. The other is that the estimates might differ from what actually happens.
David's question was akin to: "how many miles must an aeroplane fly before you scientists agree that there is no such thing as gravity".
The other point that Warren's paper barely touched on and not explicitly, which I mentioned earlier, was that this was a period during which David Rose wrote a lot of misleading and plain wrong articles about climate science. Here are two examples of David Rose headlines at the Mail, remembering that the press conference was held toward the end of September 2013:
- And now it's global COOLING! Return of Arctic ice cap as it grows by 29% in a year - 8 September 2013 (HotWhopper article)
- Global warming is just HALF what we said: World's top climate scientists admit computers got the effects of greenhouse gases wrong - 14 September 2013 (HotWhopper article)
The IPCC even put out a press release, correcting something in one of David Rose's articles, where he claimed the scheduled meeting of the IPCC was a "crisis meeting"!
Various attempts were made by the IPCC speakers to downplay the importance of the pause. Stocker repeatedly pinpointed a lack of published literature as a problem and claimed that temperature trends that last for less than 30 years should be treated as significantly less important than trends that last more than 30 years. This `temporal segmentation' enabled the pause to be dismissed as scientifically irrelevant, suggesting that journalists' questions on thematter could be ignored.
Jarraud offered just such a dismissal to Rose's question, which he claimed was 'from a scientific point of view...what we would call an ill-posed question'' (L827 828), essentially dismissing Rose as scientifically illiterate. The terms of this dismissal, however, seem inconsistent with the temporally localized claims made by speakers during the press conference. The speakers oscillated between two positions: one of broad certainty but little public meaning, the other of public meaning but little broad certainty.Yes, many of us took it that David was being put in his place for making so many false claims in the weeks leading up to the release of the IPCC report. Whether that was how it was intended I cannot say. Intentional or not, David Rose certainly deserved being put in his place.
[Note: Victor Venema pointed out in the comments that the above passage is most probably not an accurate reflection of what Thomas Stocker would have said. He didn't say anything like that in reply to David Rose. Neither did Michel Jarraud. About the closest that Thomas Stocker mentioned in regard to thirty years was in this passage, which was not a response to David Rose but at another time: "an old rule says that climate relevant trends should not be calculated for periods of less than around thirty years, that these periods are less relevant for the change, the projection of changes in the future." Which is not quite the same thing. There's a transcript in the supplement to the article. And the authors took a very subjective and unscientific view of what Michel Jarraud said, too. See the passages I quoted up higher, which puts his comments in context. Sou 8:41 am]
You'll notice that Gregory and Warren employ the trick used by David Rose (and Anthony Watts), with the word "claimed". They also can't tell the difference between an increasingly hot planet (the decadal trend), short term variability in the temperature trend, and the longer term climate change. Here's a chart of decadal temperatures. The second column from the right is the decade 2001-2010, which as you can see is much warmer than it was in the 1990s:
Warren and Gregory seem to be even more scientifically illiterate than David Rose is. The other journalists at the IPCC press conference were, in the main, much better informed about climate science.
In their paper they make much of the different time scales used in climate science. They used the term "temporally local" a lot. They wrote:
The IPCC has been able to establish greater certainty around AGW (Fig. 1), but attempts by the IPCC press conference speakers to ground their conclusions with reference to temporally local, publicly meaningful events (Fig. 2) threatened the credibility of the certainty they wished to convey This was not lost on the assembled media, whose questions prompted an incoherently oscillating position regarding the appropriate timescales to be considered within climate scienceI looked over the transcript the authors provided and I can't say I agree. There was no incoherence that I saw. The journalists who asked the questions, with the exception of David Rose and one chap from Bloomberg, seemed to be very comfortable with the time frames used in climate science.
The authors also had a blog article
Journalists repeatedly asked scientists about the pause and, in particular, how they could be increasingly certain about climate change in the face of such an uncertainty:
What they mean is that of the 18 people who asked a question, only four referred in any way to the so-called "hiatus". Roger Harrabin from the BBC asked one question about the "hiatus", Pilita Clark asked one question, and David Rose asked his different question twice. Someone from Bloomberg asked why the section on the past 15 years was included. In contrast to David Rose's loaded question about models, most of the questions indicated a reasonable depth of knowledge about climate science.
The authors give a token acknowledgement to David Rose being a disinformer about climate science, writing:
We do not wish to claim here that Rose was particularly sympathetic to the IPCC before the press conference, but in this instance his question was well founded. It exposed how attempts during the press conference to increase public meaning undermined the very scientific certainty that representatives were trying to communicate, and then leverage, to procure public meaning.Warren and Gregory provide no evidence that David's dumb question was "well-founded". Perhaps they meant that questions that are dumb needed to be answered as if the person asking the question was completely ignorant about climate science and climate models. Maybe so or maybe not. I think that such an approach would not be a good idea, because it would mean over-simplifying the science. Many of the journalists in attendance demonstrated that they were well informed about the subject and it would have been a waste of their time to talk down to them.
The whole point of a the press conference was to talk to the people who were going to communicate with the general public. If the Mail wanted to send a scientifically illiterate denier to do the reporting, that's a disservice to its readers. Other papers and media services were not as disdainful of their audience, and would not have appreciated a dumbed down version.
There is one positive in the paper. It does make you think about how people conceptualise climate. The notion of bringing greater clarity to the different time frames used for different things, is probably worth bearing in mind.
Addendum - topics of interest to journalists
Reading the paper in Nature Climate Change, you could be forgiven for thinking the IPCC press conference was all about the so-called "hiatus". It wasn't. Not by a long shot. Here is a overview, indicating the topics of the questions asked by journalists, in the order they were asked:
- Predictions of the so-called "pause"
- Which scenarios are closest to reality?
- Informing the global climate treaty discussions
- The carbon budget - how do we keep within the budget. How to prevent the burning all the fossil fuels?
- Quantifying the reductions required to stay below 2 degrees
- Downscaling of climate models to the regional level, the hydrological cycle, and linkages between ice thickness, ice cover, and precipitation in Europe.
- Will Germany's shift away from fossil fuels make a difference?
- The robustness of climate models given the recent slowdown in warming
- Climate sensitivity
- Impact of this report on climate negotiations regarding developing countries
- Sea level rise - are faster rises now rejected?
- Climate sensitivity and how much time we have to mitigate
- Why was a fifteen year period discussed in the report?
- The atlas of regional projections - what is the resolution?
- Changes to the report in regard to the recent period (so-called "hiatus")
- The number of governments who explicitly approved the report.
- On the more pessimistic projections for sea level rise.
- Climate sensitivity and deep ocean warming.
From the WUWT comments
Mostly the "thoughts" were the usual - many could have been written under any of the hundreds of denier articles on any topic at all. WUWT is just a board where deniers post their random "thoughts" of denial.
June 8, 2015 at 9:17 am
This is of course the problem with untruths’ and half-truths, the liar cannot remember what he/she said.
June 8, 2015 at 11:12 am
Agreed. To many lies and too many liars.
logiclogiclogic doesn't know there was a section inserted into the IPCC report on the so-called "hiatus". Nor that temperatures have been at record levels for several months now.
June 8, 2015 at 9:46 am
It is incredibly inconsistent that the IPCC doesn’t recognize the pause which is now 18 years 6 months according to RSS and very similar to UAH is now nearly as long as the warming which lasted from 1975-1998. Since the pause is likely to continue due to AMO/PDO for at least 10 years more it is likely the pause will exceed the duration of the rise. At some point they will have to publicly admit it is significant.
J wants a congressional inquiry. Not sure where he or she lives - but that's not such a bad idea.
June 8, 2015 at 11:22 am
They will adjust it away, like with the most recent Karl paper.
The subtleties will escape the popular press and most people’s consciousness.
That is why it is important to keep up the publicity on the problems with the adjustments.
A congressional inquiry into GISS and NOAA adjustments is in order.
sciguy54 is from the northern hemisphere is my guess
June 8, 2015 at 10:29 am
Interesting article, but it avoids the elephant in the room:
“the decade 2001 onwards having been the hottest, the warmest that we have seen”
This is not only highly uncertain, it is almost certainly false if “we” includes our Minoan and Roman ancestors. If we are only willing to include our literal selves within the figurative “we”, then a significant percentage of “we” have never experienced a statistically significant climate warming of any kind.
Unlike the journalists at the press conference, ferd berple can't get his head around the fact that there was a bit of a slow down in surface warming during the hottest decade on record
June 8, 2015 at 10:37 am
False science leads to contradictions, while the truth has no end. The contradiction between “the hottest decade” and “15 years is too short” exposed the IPCC position as being false. Surprisingly, the scientists involved could not see the contradiction, but the reporters did.
It is only now, 2 years later, that another group of researchers has finally discovered the scientists contradicted themselves. The IPCC was not up to the task. It could not discover its own errors.
MCourtney can't tell the difference between science and faith - like most people at WUWT.
June 8, 2015 at 11:33 am
Has anyone noticed that the definition of ‘scientific certainty’ is “too far away to test”.
And has anyone noticed that the definition of ‘climate change over a couple of decades’ is “overwhelmed by noise and so without meaningful test”.
In climate science nothing is testable.
So is it science or faith?
References and further reading
Certainty and meaning? - ATTP has also written about this paper
- The IPCC climate message is clear based on the evidence: The fundamental flaws of Hollin & Pearce - about the NCC comment now published - 24 October 2015
- The latest climate science from the IPCC and some early reactions September 2013
- Tricks used by David Rose, denier "journalist", to deceive January 2015
- Disinformer David Rose of the Daily Mail takes another denialist "swinge" September 2013
- David Rose and his tabloid "reporting" of Arctic sea ice and other nonsense September 2013
- Anthony Watts repeats David Rose's fibs and more denier weirdness from WUWT September 2013
- Deniers have lost it - utterly, completely - it's the heat! January 2015
- Climate change is like a nice warm bubble bath? Featuring Warren Pearce August 2013