Bishop Hill The Lords do battle
Jul 26, 2013 Climate: sensitivity Deben Matt Ridley After the House of Lords debate on the Energy Bill, Lord Deben wrote to a group of peers attacking the statements made by Matt Ridley in the debate. The letter and the ensuing correspondence was as follows:
Deben's first letter was sent on 4 July 2013:
My Lords,
During the debate on July 2, on the Energy Bill, I stated that the arguments on the science presented by my noble friend Lord Ridley were at variance with the views of the overwhelming majority of scientists whose expertise bears on these issues. I owe it to Lord Lawson, upon whom I intervened, and the noble Viscount to justify that statement. I therefore list the basis for that assertion and append two recent articles which address the points that he raised.
- Climate sensitivity measures the increase in temperature due to a doubling of carbon in the atmosphere.
- Climate sensitivity has always been uncertain, and remains so.
- When we, the Committee on Climate Change, advised the Government and Parliament on the 2050 target in the Climate Change Act, we modelled climate sensitivity on the range suggested by the IPCC.
- There have been a number of studies since then which have found climate sensitivity within the range that we modelled, some at the lower end of the range, and some at the higher end of the range.
- There is no scientific evidence to suggest that the range has significantly changed, or that the probability distribution within this range has significantly changed.
- Matt Ridley draws in particular on a recent study published in Nature Geoscience, which gives a best estimate of climate sensitivity at the low end of IPCC range. However, this study makes assumptions on highly uncertain variables, and should not be regarded as definitive (as no single study should be).
- It is appropriate to consider the full range of uncertainty in order to make decisions that appropriately balance future risks.
- Assessment against the full range of uncertainty suggests the need to cut UK emissions by at least 80% in 2050 as part of global emissions reductions to limit risks of dangerous climate change.
- Within this, it is essential to move to a low-carbon power sector. Not to do this would raise the costs and risks of meeting the 2050 target.
The following articles provide additional support:
This article provides a useful summary of the evidence on climate sensitivity and also highlights the issues surrounding the use of climate science in mainstream media articles. In mainstream explanation, such as in The Economist, climate science is often misunderstood and there is a failure to adequately reflect complexities and uncertainties. The article concludes that the evidence on climate sensitivity is such that we need to reduce emissions significantly in order to limit the risks of very dangerous climate change that we currently face.
This article focuses on how Matt Ridley misinterprets the science and highlights that there is more than one way to estimate climate sensitivity. There is emphasis on the range of estimates of climate sensitivity within climate models, and from other methodological approaches. The fact that a particular study suggests a lower estimate of climate sensitivity does not mean that all other evidence should now be negated. Rather, new studies should be considered in the context of the vast evidence base that exists. While some (notably Matt Ridley) have taken the results of particular studies and rejected this wider evidence, it is essential to consider the evidence base as a whole. The article concludes that the range of estimates of climate sensitivity remains unchanged, and that urgent action is required to reduce global emissions.
Lord Deben
Later the same day, Ridley replied as follows:
My Lords,
My noble friend Lord Deben has written to you today on the topic of climate sensitivity to justify what he said about my speech in the debate in Grand Committee last Tuesday. I am delighted to have the opportunity to respond, because the evidence he links to in fact rather well support the points I made. He said in the debate that the “facts that were presented [by me] would be denied by almost every climatologist in the world”, yet the sources that he supplies in his email actually vindicate the remarks I made, as I detail below.
For example, I said that the full greenhouse effect of a doubling of carbon dioxide is about 1.2C of warming. Lord Deben refers to the article by Dana Nuccitelli in the Guardian, which explicitly confirms that I am correct: “if we double the amount of carbon dioxide in the atmosphere, the increased greenhouse effect will cause the planet's average surface temperature to warm about 1.2°C (2.2°F) in response.” While I would not rely on the Guardian for accuracy, this is indeed widely agreed by scientists. So this point alone makes Lord Deben’s assertion that my facts would be denied by almost every climatologist false.
I am delighted to have this opportunity of emphasizing the general agreement among scientists on this point because it is often overlooked among journalists and politicians thatdoubling carbon dioxide alone cannot produce dangerous levels of global warming. As I said in the debate, this risk comes from putative net water-vapour and cloud feedbacks, as confirmed in Mr Nuccitelli’s Guardian article cited by Lord Deben. Mr Nuccitelli claims that a recent study finds water vapour concentration rising as predicted in the models. But this is just one paper and others find no such effect. For example a paper published last year concluded:
“Therefore, at this time, we can neither prove nor disprove a robust trend in the global water vapor data.”
http://onlinelibrary.wiley.com/doi/10.1029/2012GL052094/abstract
And a recent essay summarized the data thus:
“Climate models predict upper atmosphere moistening which triples the greenhouse effect from man-made carbon dioxide emissions. The new satellite data from the NASA water vapor project shows declining upper atmosphere water vapor during the period 1988 to 2001. It is the best available data for water vapor because it has global coverage.”
(http://www.friendsofscience.org/assets/documents/NVAP_March2013.pdf)
Besides, the IPCC AR4 report itself is clear that on top of any effect from water vapour, changes in clouds can either amplify or dampen warming by at least as much as water vapour and CO2, so there is no consensus about likely amplification of CO2-induced warming.
Furthermore, as I stated in my speech, the empirical data on global mean temperature confirm that warming has been much slower than predicted in all models, as shown in the following chart from Reading University, used by The Economist:
Lord Deben claims that I have chosen a few unrepresentative studies of climate sensitivity. This is not the case. I show below a chart on which are the 95% confidence intervals for observationally-based peer-reviewed studies on climate sensitivity published since 2010, all of which are on average lower than the IPCC’s central 3C estimate. Far from me being the one who is cherry-picking a study to suit my prejudices, it is Mr Nuccitelli who is cherry-picking by citing a single study of climate sensitivity that gives a climate sensitivity estimate based on a number of sources, all of which are derived from paleoclimate work, a notoriously unreliable way of estimating this variable.
Many climate sensitivity studies depend on highly complex global climate models (GCMs), and reflect the characteristics of the model concerned rather than those of the real climate. Even GCM-based studies that purport to provide properly observationally-constrained estimates of climate sensitivity, by running many simulations of the GCM with different parameter settings and comparing the results withobservations, may in fact rule out a priori the possibility of climate sensitivity being below the IPCC likely range. A good example is two recentstudies by Met Office scientists, Sexton et al 2012 and Harris et al 2013, the techniques of which formed the basis for UKCP09, a set of projections for UK climate for the 21st century. The use of the Met Office's HadCM3 model for these studies guaranteed that they would produce high climate sensitivity estimates, almost regardless of what best estimates the observational data used pointed to.
In case I should be accused of misrepresenting the studies finding low climate sensitivity, let me quote from them directly:
From Ring et al. (2012):
“Additionally, our estimates of climate sensitivity using our [simple climate model] and the four instrumental temperature records range from about 1.5°C to 2.0°C. These are on the low end of the estimates in the IPCC’s Fourth Assessment Report. So, while we find that most of the observed warming is due to human emissions of [long-lived greenhouse gases], future warming based on these estimations will grow more slowly compared to that under the IPCC’s “likely” range of climate sensitivity, from 2.0°C to 4.5°C.”
From van Hateren (2012):
“The millennium-scale response to doubling of the CO2 concentration found here, 2.0 ± 0.3°C, thus has presumably not yet reached full equilibrium, and can therefore only be cautiously compared with the equilibrium climate response of the 2007 IPCC report (Meehl et al 2007). It is at the lower end of the range considered likely (2-4.5°C), and lower than its best estimate (3°C).”
From Aldrin et al. (2012):
“The mean is 2.0°C… which is lower than the IPCC estimate from the IPCC Fourth Assessment Report (IPCC,2007), but this estimate increases if an extra forcing component is added, see the following text. The 95% credible interval (CI) ranges from 1.1°C to 4.3°C, whereas the 90% CI ranges from 1.2°C to 3.5°C.”
From Masters (2013) (not yet included in the chart):
"This method yields a median estimate for ECS [equilibrium climate sensitivity] of 1.98 K, with a likely (67 %) range of 1.47–2.95 K and a 90 % confidence interval of 1.19–5.15 K." (1 K = 1°C).
From Lewis (2013, in press [Journal of Climate]):
"Employing the improved methodology, preferred 90% bounds of 1.2-2.2 K for ECS are then derived (mode and median 1.6 K). ...Incorporating forcing and observational surface temperature uncertainties, unlike in the original study, widens the 90% range to 1.0-3.0 K."
In addition, there is the Otto et al (2013) study in Nature Geoscience to which I referred in my speech and which has been characterized as follows by one of its authors, Nic Lewis:
“Using what is probably the most robust method available, it establishes a well-constrained best estimate for TCR that is nearly 30% below the CMIP5 multimodel mean TCR of 1.8°C (per Forster et al. (2013), here). The 95% confidence bound for the Nature Geoscience paper’s 1.3°C TCR best estimate indicates some of the highest-response general circulation models (GCMs) have TCRs that are inconsistent with recent observed changes. Some two-thirds of the CMIP5 models analysed in Forster et. al (2013) have TCRs that lie above the top of the ‘likely’ range for that best estimate, and all the CMIP5 models analysed have an ECS that exceeds the Nature Geoscience paper’s 2.0°C best estimate of ECS. The CMIP5 GCM with the highest TCR, per the Forster et. al (2013) analysis, is the UK Met. Office’s flagship HadGEM2-ES model. It has a TCR of 2.5°C, nearly double the Nature Geoscience paper’s best estimate of 1.3°C and 0.5°C beyond the top of the 5–95% uncertainty range.”
Mr Lewis has also written as follows in response to a comment from Mr Nuccitelli:
“If climate sensitivity is two-thirds or less than the IPCC's central estimate, then for any greenhouse gas emissions scenario ultimate anthropogenic global warming will be at least a third less than previously expected.”
In short, I stand by my assertion in the debate that recent scientific opinion has not been moving in the direction of greater alarm, but the reverse.
I am surprised that Lord Deben should cite an article on a blog called the Carbon Brief. This was based largely on a Guardian article by Myles Allen, which misrepresented me. I append below the text of a letter I wrote to Professor Allen in response.
Finally, I am delighted to see Lord Deben concede that "Climate sensitivity has always been uncertain, and remains so". However, this flies in the fact of his repeated assertions of sufficient certainty about climate risk to base veryexpensive policy upon it.
Yours sincerely,
Matt Ridley.
The following day, Deben had another go.
My Lords,
In his response to my explanation, Viscount Ridley dismisses vast swathes of the scientific evidence base:
- He assumes away positive feedbacks which amplify the initial warming due to increased carbon in the atmosphere, without having robust evidence to justify this.
- He rejects climate modelling, and methodologies which estimate climate sensitivity based on historical data, both of which are major areas of research.
- He focuses on a particular study within the energy balance modelling approach. What he doesn’t say is that this paper suggests estimates of climate sensitivity that are largely unchanged based on recent temperature data, and that it implies the need to cut global emissions significantly in order to limit currently high risks of very dangerous climate change. Neither does he refer to other studies within this approach which find a higher sensitivity. He does not highlight the limitations of energy balance modelling, which is no more certain than climate modelling.
It is the job of the Committee on Climate Change to consider the scientific evidence in its entirety, and in a balanced and open-minded way. The scientific evidence continues to suggest significant risks of very dangerous climate change. We should insure against this through reducing emissions, which we can do at relatively low cost.
I do not propose to continue this discussion further in public but will instead seek to arrange a meeting between Viscount Ridley and the climate scientists who work for the Committee on Climate Change.
Lord Deben
And finally
6.7.13
My Lords,
Lord Deben has once again written to you. In response, briefly, to his letter I would make three points:
First, far from "assuming away" positive feedbacks that amplify the initial warming due to increased carbondioxide levels, I pointed out that recent observational evidence pointed topositive feedbacks in the real world being much weaker than those exhibitedwithin complex global climate models' virtual worlds.
Second, I am always happy to meet any scientists to discuss climate change. It would be most profitable if we wereaccompanied by other scientists who have reached different conclusionsthan those the CCC has consulted, so that the exchange could be a two-way one. I assume Lord Deben would agree to attend also.
Third, you should know that this is not the first time I have been wrongly cited in this way. Lord Deben made an unprovoked attack on me several months ago in a lecture in Oxford, charging – on the basis of a blog post written by a novelist – that I had not cited the mainstream scientific literature when writing about ocean acidification. In fact I had included direct quotations from 17 papers in the mainstream scientific literature, including a major meta-analysis of 372 peer-reviewed papers. Despite being requested twice to do so, LordDeben declined to write to the organisers of the lecture to correct his mistake.
Yours sincerely
Matt Ridley
Bishop Hill
I inadvertently missed the final email in this exchange. I've added it now, so if you read the original post before 9:30 you might like to revisit.
Reader Comments (75)
citing Dana's Guardian blog!
"We should insure against this through reducing emissions, which we can do at relatively low cost."
Aside from the jaw-dropping assertion about 'low cost' (which may say more about Deben's perception of expense than anything) the question I should really like him to answer is Lord Donoghue's about the overall impact of UK emission reductions, expressed as a temperature value.
Either he knows this is vanishingly small, and would need to be water-boarded to admit it, or he's blissfully unaware of it, and in the wrong job.
"citing Dana's Guardian blog!"
Yup Barry, about as far as our elected representatives go when carrying out due diligence!
Edit, they are elected, are they not? Oh...
"Deben refers to the article by Dana Nuccitelli in the Guardian"
Good Lord!!
However, the public, whose well being you are in office to protect, will certainly continue this discussion and through the resultant due diligence also carry out your responsibilities for you! You are in safe hands Lord Deben, the public really do take their responsibilities seriously and rest assured they have your best interests to heart.
'the climate scientists who work for the Committee on Climate Change'
There appears to be only one who remotely fits the bill....Brian Hoskins. None of the others are conceivably 'climate scientists'
The not continuing in public is probably because Debden is way out of his depth and cannot continue in public. Citing blogs is something the Wikipedia climate alarmists and Real climate have sneered at when dismissing counter views. The Viscount is to be pacified and re-educated in private, I'm sure he will reply offering a public meeting with his own scientists present as Lord Lawson offered the RC when he was similarly placed in this position.
"He assumes away positive feedbacks which amplify the initial warming due to increased carbon in the atmosphere, without having robust evidence to justify this"
Should not the good Lord be able to cite the "robust evidence" on which he assumes away Ridleys "assuming away"? Ridley has provided a rationale for doubting both models and paleoclimatic studies, one wonders where is Debens rationale for uncritically accepting them?
Clearly, regardless of the way the matter is dressed up, Debden blindly accepts that feedback is always strongly positive. We all know that without this assumption (guess) CAGW is a non starter. The climate sensitivity is a little over 1degree C.
Will Viscount Ridley be allowed to bring climate scientists or is this intended to be re-education by the Thinkpol
No doubt the planned meeting involves the DECC scientists giving Matt Ridley advice on climate science. Echos of Nurse and the RS. Avoid open debate at all costs.
TC
Will Viscount Ridley be allowed to bring climate scientists or is this intended to be re-education by the Thinkpol
Jul 26, 2013 at 8:54 AM | Unregistered CommenterTerryS
Same trick as nutty nurse pulled, re-education. Arrogant cheat.
> Debden blindly accepts that feedback is always strongly positive
Deben finds it both politically and financially beneficial to have feedback as strongly positive. What he believes is another matter.
I'm sorry. I know this is terrifying, but it made me laugh.
"He assumes away positive feedbacks which amplify the initial warming due to increased carbon in the atmosphere, without having robust evidence to justify this.
The stupid! It hurts.
Without the feedbacks the Alarmists have never had anything. And they've never had any evidence for the feedbacks.
I wonder if Mark Lynas is still proud of his '6 Degrees' book. Shouldn't he hand back the advance and royalties?
It is gratifying to see that, as Lord Deben, Mr John Gummer now fully embraces the Precautionary Principle.
I wonder if his daughter still enjoys beefburgers as much as she did back in the good, old 'Mad Cow' days!
What is a "climatologist"? Is there a recognised definition of their skill set and expertise?
Please can we have the names of the "climate scientists" who work for the CCC?
IMO, the pattern of ducking out of debate and offering "meetings" with these nameless experts needs direct challenge on the record by asking "Who are the experts you refer to?".
So Deben believes it is in our best interests to listen to a blogger ( dana ) who works for an oil company?
Deben fails to quote or even explicitly refer to any climate scientist and/or peer reviewed article.
We've won.
Remember that Deben, in a speech at Oxford University, compared the scientific consensus to the teachings of the Catholic Church, and the views of sceptics to the opinions of a renegade Christian such as Cliff Richard.
Citing Nuccitelli counts as a return to sanity for Deben.
What a piece of work Lord Deben is!
Not only is he ignorant of the science but he does not care what the public thinks about the conflicts of interest his financial associations seem to give him.
Interestingly he doesn't want to pursue this discussion in public! I bet, not only will the public see his limited level of understanding, but also begin to question his reasons for taking this stand point. I hope it stays in public where it belongs!
The government could hold an "auction" among climate scientists to get a value for climate sensitivity that would suit its policies.
"Do I hear 2.9C, 3.0, ... 4.2, ... any advance on 4.2C? Done!"
Otter
Some bloggers are worth listening to - try the Bishop at the House of Commons SciTech Committee.- and I believe he is still waiting for his Big Oil cheque.
http://bishophill.squarespace.com/blog/2013/7/17/bishop-in-the-commons.html
"What is a "climatologist"? Is there a recognised definition of their skill set and expertise?
Please can we have the names of the "climate scientists" who work for the CCC?"
Seconded. List please.
Climate sensitivity measures the increase in temperature due to a doubling of carbon in the atmosphere.
Now is that graphite, or perhaps diamond, or graphene, or lonsdaleite?
Lord Drebin* is talking (bucky)balls.
Oh sorry, that was the guy in "Naked Gun." Maybe the Lord is an allotrope.
Now we know why Deben might "not propose to continue this discussion further in public".
I can't find the original - but it was likely Thorbjørn Berntsen, Norwegian Environment Minister in 1993 who, on the Norwegian equivalent of the 6 o'clock national TV news - called Gummer a drittsekk - Thorbjørn's out of government but other things haven't changed.
I repeat my call for some far more robust language in our Houses of Parliament.
Long past time where direct insults were wheeled out.
Deben is one of the many troughers who should be held to account for the huge damage and harm they are doing to this country and its people. Their sheer greed and lack of integrity is astounding.
Lord Deben's degree was in History which acquits him well to be an expert on Climate Alchemy........
Deben, Nurse, Gore, Mann, Schmidt (at that hilarious debacle of an interview when he would not stay in the same room as Dr Spencer and kept running behind the curtain like a kid pissing his pants) As soon as they lose the argument they go and hide under a stone like the slimy creatures that they are. I have nothing but contempt for the lot of them.
(When I insult someone I use my own name)
Ivor Ward aka Disko Troop
Imagine string theory or some such being discussed this way, the repugnancy of the situation would be face smashing. Only in climatology!
Deben the Disingenuous.
"When we ..... advised the Government ..... on the 2050 target in the Climate Change Act, we modelled climate sensitivity on the range suggested by the IPCC."
Should actually be: "When we ..... advised the Government ..... on the 2050 target in the Climate Change Act, we modelled climate sensitivity on a range suggested by the IPCC."
And why did they not have the First Prince of Warming, Charles, drop by to straighten it all out?
These people are desperately hanging onto the Power the CCA and the CCC gave them when that power is being opposed by our elite Establishment which has rightfully decided to fight these creeps.
DEEBEE (Jul 26, 2013 at 10:45 AM), string theory *would* be discussed in this way if wielded similar political and economic 'benefits'.
Good that the noble lord revealed his sources this way. They cannot cite original sources because they need a hymn sheet to sing from.
I must agree with Phillip Bratby the troughers must be brought to account. They are making shedloads of money off the poor and vulnerable, we cannot afford their "pie in the sky" dreams. The emissions from this country are dwarfed by those of China, India and other growing Nations, so much so that we cannot have any effect. Mind you, no one can whatever they do. I do not believe that puny man can even pretend to control the climate, even the weather is beyond our control. And that is without mentioning the drastic effect a shortage of CO2, if these others followed our lead, would have on the environment, no plants growing, no greenery.....no food! There are also a few volcanoes around the world, just how does Deben propose stopping the vast amounts of CO2 pouring out of them?
I wonder what Grauniad Central thinks about that? If they start looking into the matter, they may suddenly realise why their reputation for even trying to support free speech is in tatters. All as a result of antipodean 'climate-refugee' moderation imported from the blog-that-cannot-be-named.
To summarise the above:
Lord Deben:
A. Is conflicted by his Directorships.
B. Invokes the anti-science "precautionary principle".
C. Hinges his argument on an unscientific "Climate Sensitivity" constant. This so called constant is an artifice for which no experimental test does or can exist.
I respectfully submit his position is indefensible.
"Lord Deben's degree was in History which acquits him well to be an expert on Climate Alchemy........"
My opinion of Deben is not fit to print but this comment is irrelevant. Let's focus on the arguments backed by references and the facts cited therein. They withstand scrutiny or not irrespective of the background of the protagonist.
The whole thing is now upside down. Those of a sceptical disposition cite peer-reviewed publications and the defenders of climate orthodoxy peddle blogs. Heh.
shub
"The whole thing is now upside down......"
Excellent observation shub!
Ridley quoted by Green Sand:
Ridley is being kind referring to Deben’s source as a “novelist”. In fact Deben’s only factual source for his attack on Ridley was an article (in Guardian Environment, of course) written by a depressive hippy who’s idea of a good time is smoking reefers with primitive tribespeople in the Amazon. Deben describes her as his “good friend”. Perhaps she shares her stash with him.@alleagra: How's this for facts?
Climate Alchemy exaggerates CO2-AGW by at least a factor of 30. Deben is a trougher. The troughers have been cleverly used by the Marxists to destroy capitalism and replace our government with CO2-justified totalitarianism, the ruling caste to be the same corrupt academics who created the fake science.
Ouch.
Elegantly yet brutally done.
Deben's second letter has this quote: "The scientific evidence continues to suggest significant risks of very dangerous climate change." It doesn't say, "The scientific evidence continues to suggest very significant risks of dangerous climate change." To my mind the position of the emphasis is striking and represents some modest scene-shifting.
Equally, he goes on to say, "we should insure against this through reducing emissions, which we can do at relatively low cost," echoing the "insurance policy" get-out clause used by Davey (the low cost sop is patently nonsense).
Given these things are usually drafted carefully, it suggests things are changing - the way they usually change when policy shifts are in the air (i.e. at a glacial pace).
Bishop -
On IE8, the post only displays through the final Ridley quote, truncating your update line and comments. Something odd in the HTML code, no doubt. Works fine on Firefox 22.0 and on my Android-powered phone, though.
All the positive feedbacks mentioned are actually negative, (clouds certainly are).
A doubling of CO2 will have zero effect. It's the sun! The sun is the only heat source to drive climate.
John Gummer (we can quibble about his nobility) has always been happy to live high on the public purse:
http://www.telegraph.co.uk/news/newstopics/mps-expenses/5301734/John-Gummer-claimed-more-than-9000-a-year-for-gardening-on-MPs-expenses.html
The circularity of his use of the CCC to enforce the idiocies of the Climate Change Act is a conflict of interest in itself. He represents all that has gone wrong in British politics.
Dana, in the employ of big oil and gas, seeks to wreck the coal industry by raising fears about a climate crisis. The lack of facts to support the war on coal by Dana and his fellow extremists is well established. The correlation between Dana with the interests of big oil and gas is remarkable.
The use of Dana's unreliable and self serving hype by anyone in government who claims to care about the public interest is questionable at best.
Likewise IE9. The implication, of course, is they have no way of letting you know using their regular browser. Works OK with Google Chrome.