Bishop Hill Reacting to Rose
Mar 18, 2013 Climate: Models Climate: Surface Climate: sensitivity In the wake of David Rose's Mail on Sunday article yesterday, Piers Forster tweeted that he was unimpressed with the article. I asked him if he would be willing to set out why in a bit more detail and this is his response:
It's fine to say that current models overestimate the last decade of warming. They clearly do, and as I say in my quote I think we can rule out some high sensitivity values because of this. But to do a far comparison you need to remove the effects of variability. Note also that some model runs also get the temperature evolution pretty right - although the majority don't. Even with a suggested ECS of around 2.5 C or so we can end up with a very significant climate change by 2100 if we don't do something - therefore I think the tone of the article in terms of its implications for the IPCC, climate science and the climate itself are all wrong.
He also sent the full quote that he gave Rose for his article, which gives some context.
Basically, the climate sensitivity has always been very uncertain. > estimates have put it somewhere between 1 to 5 C for a doubling of CO2. The IPCC best estimate has been around 3C. The fact that global surface temps haven't risen in the last 15 years, combined with good knowledge of the forcing terms changing climate over the satellite era: greenhouse gases, volcanoes, solar changes and aerosol is beginning to make the high estimates unlikely. Given this, i would put the best estimate using this evidence around 2.5 C. There are still uncertainties though particularly in heat going into the ocean, but climate sensitivities above 3.5C or so don't seem to fit. Keep in mind that this is only one line of evidence for quantifying climate sensitivity. Other lines of evidence have been able to firm up the bottom end. We now have good observational evidence for a positive water vapour feedback and even clouds, which have always been the largest headache in climate change, are beginning to be understood and a positive cloud feedback is looking more likely. This line of evidence helps rule out climate sensitivities below 2C. So I see it very much as a positive story that careful science ( and time) is helping to reduce the most significant uncertainty in climate science.
This thread will be tightly moderated for tone and relevance.
Reader Comments (187)
"This line of evidence helps rule out climate sensitivities below 2C."
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That is the weakest point in Forster reply, as observational study after study is coming out with a central sensitivity around or below 2 degrees. Even some older AR4 observational studies now confirm this after correction for errors in Bayesian statistics.
And again, these are CENTRAL observational estimates. Their range goes well around this value, and to "rule out climate sensitivities below 2C" would just ignore observational data and peer reviewed science and replace those with models and opinions..
There is, of course, a credibility problem arising with a 1.6C most likely estimate (as proposed by Nick Lewis) as it would be even below the decade old estimate from Pat Michaels of 1.9C, who was labelled No. 7 of Monbiot's top 10 deniers list.
1.6C would also be closer to Lindzen's and Spencer's estimate than to the previous AR4 value.
And it is even half way between the previous AR4 value and a value of 0, the value of total denial of any effect of CO2 on global temperature.
Don Keiller,
Having recently suffered an execrable presentation from a senior colleague recently about the threat to my sector from climate extremes, I'd be very keen to provide him with an alternative point of view which doesn't come solely from my desk - your slides would be very welcome indeed.
You really must try harder:-)
Mar 18, 2013 at 10:07 PM | Don Keiller
How about this. A link to a sceptic source which comes to the same conclusion as ABC about the origin of the recent rise in CO2 via the same evidence.
http://www.ferdinand-engelbeen.be/klimaat/co2_measurements.html
Richard Whybray, you are simply dishonest. No wonder your children dont wan't to be associated with you.
Piers Forster states: "very significant climate change by 2100 if we don't do something"
[Snip -manners] In truth, nothing has been 'done' except energy impoverishment, taxation and the enrichment of the Green elite and 'Carbon' spin-meisters. Meanwhile atmospheric [CO2] has risen and the "mean" global temperature has not increased and even declined in the last eight years defying the climastrological predictions and the portents of the thirteenth sign of the Zodiac, the Schtick.
"...to do a far comparison you need to remove the effects of variability..."
Do IPCC climate models when hindcasting (when they happen to fit the historical record almost perfectly) adjust for past natural variability? Or is the natural variability adjustment only required when forecasting?
@Entropic Man
Please explain how you think Engelbeen's remarks - which are exclusively about the origin of the increased CO2, represents proof of the proposition
'that the recent warming was due to man-made CO2 rather than natural climate variability?'
It doesn't even address the point at all.
Foster relies heavily on the cloud feedback work of Dressler. Take a look at this, again from the GWPF. Look at the data Dressler uses to measure cloud feedback and the regression line he draws through it. The GWPF point out, rightly, that nobody would contemplate a regression line through such scattered data.
http://www.thegwpf.org/clouds-from-both-sides/
Martin A
I share your scepticism (and McIntyre's) about that logarithmic formula. How on earth have they established that constant 5.35? - note the implied accuracy! It's been niggling me since steve mosher logged his post (which is not the object of any criticism from me; on the contrary his post was very interesting). Where is the derivation or measurment of the constant? At what temperature and pressure does it apply (because the constant must vary with both)?
And when all that's done, we have to take our CO2 out of the lab into the atmosphere and try to establish what happens to that constant when the CO2 molecule 'cloud' is subject to convection circulation. Anyone's guess!
Garethman,
Sorry but you are way off the mark about the DM.
Their problem is not their so called bias (after all even Alastair Campbell accepts that ALL media is agenda driven these days) but that their bias runs counter to the self approved leftist bias of the BBC and its print version in the Guardian and pretty much 99% of the media outlets out there.
The very fact the DM is prepared to run stories like this should be applauded because if they didn't it would be a very quiet anti-catastrophilia scene out there. We should applaud this because ever since the BBC and the Guardian created and fuelled the fake outrage over phone hacking and using deliberate lies (dowler deleting voice mails) to end Murdocks take over of sky and kill off the UK's most popular Sunday paper, right leaning media outlets are few and far between.
Finally, the DM is the closest thing we have to Fox News. Yes I know, you have just coughed up your coffee all over your keyboard but the fact is Fox News is Americas must trusted media outlet with daylight coming second (pretty much because all the other MFM outlets sold their souls to worship his royal highness Barry "The Bringer of Loght" Obama).
Regards
Mailman
Ed Hawkins has updated his blog post with the following comment on Rose's article:
... and James Annan's reaction can be found here - clearly he thinks David Rose misrepresented him in the interview, and is indeed telling lies
(my bold)
Mar 18, 2013 at 4:33 PM | Don Keiller
Excellent. Well done. Could you make a You Tube Video? Then more of the I-Pad generation could see it.
Patagon wrote:
quote
if RH remains constant when increasing temperature that actually means a large increase in water vapour content in the atmosphere.
unquote
Which is rather the point: AIUI the models expect constant RH.
JF
Excuse my not mentioning reduced evaporation caused by the Kriegsmarine Efect, I'm off to dig in the ancient brick kiln from whence came my house. Much more fun.
But he backs off in the comments when confronted with Miles Allen's statement
I think "lies" was over-the-top rhetoric to throw a bit of red meat to his fellow believers.
Obviously worked with you!
Don Keiller
Well I hope you quoted me on the drought and CO2 enhancing plant growth issues, I've been talking about these points for years. :-)
Foxgoose
Careful with the generalisation of "believers". You don't have to subscribe to imminent climate doom, or have a particular political viewpoint or opinion on climate policy, in order to accept the basic science of anthropogenic warming. Ongoing polarisation of the debate (with offenders on both sides!) is not helpful. James is a welcome voice of moderation - I can see it is annoying for him to find himself misquoted when he's trying to make a sensible contribution. Same for Ed and Piers.
The real question is "At what point can the hypothesis that combustion leading to increased CO2 in the atmosphere leads to increased global temperatures be considered a failed hypothesis?"
At the moment it seems to me that this hypothesis can never be considered as failed. The hypothesis simply becomes continually adjusted to match the indisputable facts. At the moment we now have supporters of the hypothesis basically claiming that the reason we are not seeing increases in global temperature despite vast increases in CO2 in the atmosphere over the last 16 years is because the warming has been exactly cancelled by natural variability. Put another way, they are claiming we would be seeing huge increases in global temperature if it were not for the fact that these increases were being perfectly cancelled by unprecedented natural global cooling.
I think any other scientist would realise that it is time to get out Occam's Razor here. The reason that global temperatures are not rising is very likely nothing to do with some complex interaction of highly improbable coincident climate events. It is simply that the theory is wrong.
@ Garethman
I think the underlying difficulty is that the Daily Mail has a well earned dreadful reputation for biased reporting.
You mean the Daily Mail does not peddle the same line as the Guardian and the BBC? The coverage of "global warming" or "climate change", whatever you want to call it, by those two mouthpieces of the establishment has been an absolute disgrace and is part of the reason why the costs of energy in this country are so high, pushing up unemployment and disfiguring the countryside with wind turbines.
Bishop Hill has quite sensibly allowed Piers Forster the opportunity to explain in some detail why he disagrees with the Daily Mail article. Would Real Climate or any of the blogs supporting the Alarmist viewpoint publish something written by a sceptic? When did the Guardian or the BBC last give any significant space or airtime to sceptical views on anthropogenic climate change?
Richard: "Generally, Europe, North and South America, and Australia have seen decreases in soil moisture drought since the 1950s, although the change appears to be more towards increasing drought since the 1908s."
Now here's the problem for the sceptical layman. Dr. Slingo announced in January that we could expect more years like 2012 because of global warming. Indeed to the layman that makes sense, but then I read that drought has been increasing in Europe from her colleagues. It, of course depends on your definition of drought, the one forecast by the Met Office last year was the wettest on record I believe.
On the sensitivity point here's my take:
High Sensitivity:
1. Funding keeps flowing in to climate science research;
2. Envrionmentalist get their dream of controlling everyone's lives;
2. Prominment politicians, ther relatives and other carpetbaggers get to line their pockets.
Low Sensitivity:
1. Funding of climate science greatly reduced;
2. Environmentalists lose the chance to control everyone's lives;
3. Prominent politicians, their relatives and other carpetbaggers don't get to line their pockets.
Add to that the embarrassment of the world's finest climate scientists having gotten sensitivity wrong for 34 years (since Charnley) and the pressure for it to stay high is massive.
So, yes, I welcome James Annan's decision to let observations trump models, who knows it may be contagious.
Penultimate question for Richard. I am assuming that you recognise that there was a MWP, and a Roman and Minoan Warm Periods. So let's deal with them. Noobody has the faintest clue what the actual temperatures were, but they were warmer. Now the ecosystem cannot tell why it's gone warmer, so will react in exactly the same way to warmth whether it's caused by extra greenhouse gases or Little Green Men. So why didn't we get the catastrophes forecast by Trenberth and his cohorts in the IPCC after the MWP, Roman and Minoan periods?
I've asked this before but around 200 years ago I studied electrical engineering. Feedback, positive and negative was a vital part of circuit design. Negative feedback was wholly beneficial, while positive feedback could be disastrous. In the design of oscillators positive feedback was used to produce the single frequencies required, but without dampening they would finish on an infinite loop of increasing feedback. Here's the question. What stops the positive feedback in the climate system and holds it at a fixed sensitivity?
Remember Rutherford's maxim: "If you can't explain your theory to a barmaid, it probably isn't very good physics."
Richard Betts (9:37 AM)
Rose may have oversimplified and misrepresented what Annan said. It’s almost inevitable when a journalist is interpreting complex science for a popular audience.There are thousands of examples of environmental journalists misrepresenting the science in order to emphasise the possibility of climate catastrophe, as Professor Betts well knows, since he has been the victim of such radical misquoting.
In this rather rare (in the British press) instance of alleged misrepresentation in the other direction, Annan accuses Rose of lying, and refuses to consider anything else he says. Should we apply the same rule to IPCC reports, or Met Office websites, every time they’re found to have made a mistake?
Mar 19, 2013 at 10:03 AM | Ryan
When we see substantive cooling, comparable with the warming seen in previous decades.
We've seen a general warming trend over previous decades, with natural variability superimposed, temporarily accelerating or slowing the warming for shorter periods. The warming in the 90s was faster than expected due to AGW alone and probably had a natural component in addition to the AGW trend. If you're right, and all this is entirely natural variability (as opposed to a combination of natural variability and anthropogenic warming), then the world ought to cool again at some point.
Perhaps our 2 top experts have their places booked for the CFMIP/EUCLIPSE Meeting on Cloud Processes and Climate Feedbacks
Hamburg, Germany, 10-14th June, 2013 to discuss this White paper:
Perhaps then after the research has been done we will have a better understanding
@Richard Betts
Then let's see what Annan really said:
In Revkin's article he was quoted
"[T]here have now been several recent papers showing much the same – numerous factors including: the increase in positive forcing (CO2 and the recent work on black carbon), decrease in estimated negative forcing (aerosols), combined with the stubborn refusal of the planet to warm as had been predicted over the last decade, all makes a high climate sensitivity increasingly untenable. A value (slightly) under 2 is certainly looking a whole lot more plausible than anything above 4.5."
http://dotearth.blogs.nytimes.com/2013/02/04/a-closer-look-at-moderating-views-of-climate-sensitivity/
Later, he added a comment on his own blog:
http://julesandjames.blogspot.co.nz/2013/02/a-sensitive-matter.html
"The discerning reader will already have noted that my previous posts on the matter actually point to a value more likely on the low side of this rather than higher, and were I pressed for a more precise value, 2.5 might have been a better choice even then. But I'd rather be a little conservative than risk being too Pollyanna-ish about it."
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My interpretation would be, that his estimate "even then" of 2.5 was before the numerous new factors (reduction of aerosol cooling, increase in black carbon positive forcing, halt in temperature increase). And that was "conservative". He has not given a new estimate but the context of the new factors would support to assume a significantly lower estimate IMHO.
However, in the same Revkin article, there is a quote from Gavin Schmidt, who purports an Annan estimate: of 2.5.
"For reference, James stated that his favored number was around 2.5 deg C."
While I see support for David Rose's claim, I don't see support for Gavin Schmidt's claim. Though I would not necessarily think Gavin Schmidt lied, if he makes an untrue statement.
In the grand scheme of things, in the mid era of an interglacial, natural variation is not that large.
It is because of this and because CGMs were tuned (with various assumptions and fudge factors) to track 20th century temperatures, that one has not yet seen substantial departure between projections and reality. However, the fact that to date, reality is still just within the lower bounds of the projection is just luck and per chance, it is not because we know enough about the atmosphere and the oceans and climatic response to be able to create a worthwhile model.
However, these models have not been running for a lengthy period (circa 20 to 25 years) and reality is only just within their lower bounds. The Met Office is predicting that there will be no warming before 2017. So we should be asking ourselves:
1. If there is no warming before 2017, at that time will reality still be within the lower bounds of the projections?
2. If warming does not recommence in 2017 and instead the temperature hiatus continues, will reality be outside the lower bounds of the projections.
Anyone who does not consider that there is a serious problem with the state of computer modelling and the projections thereby produced is (with respect) dellusional.
However, it is not surprising that computer modelling is so flawed since:
1. We do not know or understand enough about the atmosphere immediately above the oceans, or
2. What is happening in the first 1 cm of the oceans; and
3. We do not know or understand enough about clouds and their variability.
If one looks at the satellite data since 1979 there is no first order correlation between CO2 levels and temperature. The temperatures were flat between 1979 and 1997 and flat between 1999 to date. There is merely an upward step around the super El Nino of 1998 which that event was caused in some way by CO2 levels, is an irrelevance when considering the climate sensitivity to CO2.
Accordingly, absence some unsubstantiated and necessarily uncertain adjustments to be made as a consequence of changes in aerosol particles, volcanoes, changes in the ozone whole, changes in cloudiness and solar insolation abd the like, one would have to conclude that at current levels of CO2 (circa 380ppm) 33 years worth of satellite data (which although it has its flaws is the best temperature data set) suggests that climate sensitivity to CO2 is so small that we cannot measure its signal within the limitations of our present equipment and technology.
Unfortunately, we have very little sampluing data of the oceans, but again the ARGO data of the past approximately 10 years suggests no measurable increase in OHC within the top few hundred metres and it is only temperature within that zone which can immediately bring about changes in global temperatures and climate. Ocean over turning from the deep is measured on a centenial scale and if there are changes in OHC below 700 metres these really are not of any immediate concern. They certainly do not justify immediate action to be taken.
Now there's a new thread i can go a bit O/T but sort of relevant.
On Youtube there's the famous Test Tube experiment with the CO2 Canister the Blow Torch and the Infra Red Camera.But the actual Test Tube is sealed up.
Question is at what Planetary Atmospheric Pressure does CO2 actually trap heat?
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Exactly.
This debate is characterised by wild hyperbole on all sides - the vast majority of it coming from Richard Bett's side of the argument. We all see stuff every day from all the sources you've mentioned - plus the BBC, the Guardian and the NYT which could easily be characterised as "lying" - except that such inflammatory allegations don't really help the discussion.
Jams Annan was embarrassed by David Rose highlighting parts of some of his earlier statements on sensitivity which attracted criticism from his colleagues - so he tried to defuse them by calling them lies.
Richard unthinkingly jumped on the bandwagon.
There is also rather an unpleasant and snobbish undertone here, exemplified by the cute little app James Annan incorporated in his blog post to block access to the Daily Mail. Because the Mail is a populist paper, read by what people like Richard and Annan see as "the great unwashed" they think they have a free pass to pass sneering generalisations on it and its readers.
For my money, David Rose is a serious and professional journalist who wrote an important piece highlighting the side of the argument that opponents would like to keep hidden.
Richard works for a well funded public organisation which has been very vocal in this debate - if he thinks Rose is lying, why doesn't the Met Office refer him to the PCC - I think we all know what the answer would be.
"...I echo the above requests for evidence of water vapour and clouds having a net positive feedback..."
I echo this echo.
The original piece does not seem to me to be robust response to AGW criticism. It seems to be a place-holder. It can be characterised as saying
"I hear your comments; they are wrong because we have some data that disproves them, but we can't actually find it at the moment. Nevertheless, they are wrong, and I have now proven this, so no one should listen to you"
This has been a common response from the AGW side, ever since McIntyre broke the first hockey-stick. There are regular assertions that the science supports AGW, coupled with an unwillingness to actually identify the specific paper or data which does the supporting. The next sentence is invariably: "Now that we have shown that the science supports AGW...."
Perhaps we should develop a shorthand word to describe this technique? It puts me very much in mind of the late great Tommy Cooper, who ran many of his tricks with this kind of verbal support. Does anyone remember the time when he magically moved a ball from under one cup to another, and then, without up-ending them to show the moved ball, announced: "And now for the hard part - moving it back again...!"
Not sure on clouds but there is this 'summary' article from science from 2009 which has references to the observational evidence for water vapour being a positive feedback
http://geotest.tamu.edu/userfiles/216/dessler09.pdf
The water vapor feedback has long been expected to strongly amplify climate changes because of the expectation that the atmosphere’s relative humidity would remain roughly constant— meaning that the specific humidity would increase at the rate of the equilibrium vapor pressure, which rises rapidly with temperature. However, observational evidence has been harder to come by, and the effect has been controversial. Much of that controversy can now be laid to rest, thanks to new observations and better theoretical understanding....
...observational evidence is crucial to determine whether models really capture the important aspects of the water vapor feedback. Such evidence is now available from satellite observations of the response of atmospheric humidity and its impacts on planetary radiation) to a number of climate variations. Observations during the seasonal cycle, the El Niño cycle, the sudden cooling after the 1991 eruption of Mount Pinatubo, and the gradual warming over recent decades all show atmospheric humidity changing in ways consistent with those predicted by global climate models, implying a strong and positive water vapor feedback...
...Thus, although there continues to be some uncertainty about its exact magnitude, the water vapor feedback is virtually certain to be strongly positive, with most evidence supporting a magnitude of 1.5 to 2.0 W/m2/K, sufficient to roughly double the warming that would otherwise occur...
The historic record of the MWP, Roman and Holocene and even going back to the dinosaurs, since the laws of physics concerning water vapour were the same back then, is incompatiable with a climate sensitivity greater than 1.Othwerwise we wouldn't have got from there to here.
Foxgoose
I only reported what James said.
The title of this thread is "Reacting to Rose". I thought the reactions of two people quoted by Rose would be quite relevant to the discussion.
Some of my own family read the Daily Mail, so if they are the "great unwashed" then so am I :-) Please don't put words into my mouth!
Richard
I read your previous quote:-
.... as an endorsement of Annan's statement - the inserted comma and the word "indeed" seemed to imply that; however english syntax isn't my strength and, if you simply intended to report what he said, rather than support it - I apologise.
I'm sorry also if I wrongly linked you to his anti Mail sneering.
Now that we've got that out of the way, would you mind telling us what your own general opinion of Rose's article was?
Richard:
"The warming in the 90s was faster than expected due to AGW alone and probably had a natural component in addition to the AGW trend."
How do you know this for sure..
When we had similar rapid warming periods, earlier in the temp record.. (why not just a repeat if the same natural processes, some of which, or the degree of could be unknown.)
date/length/rate/sig
1860-1880 21 0.163 Yes
1910-1940 31 0.15 Yes
1975-1998 24 0.166 Yes
1975-2009 35 0.161 Yes
you just cannot make that statement with certainty.
And it will be amusing to see backtracking if it cools slightly for a decade or 2.
Which I would NOT bet against
All that I can see is a gradual long term trend of warming,.. for over a hundred and fifty years and a AGW signal absent (which would appear to be natural, processes and cause poorly understood)
Is the much-sought-but-missing equatorial tropospheric-hotspot not also supposed to be evidence of positive water vapour feedback?
Or does it's absence indicate that the models cannot adequately model CO2 without water feedback?
Foxgoose
It was good to see David Rose speak so highly of Met Office science, calling HadCRUT4 "impeccable". Hopefully all sides are now agreed that the observational datasets are reliable.
Much of the article is David's opinion on climate policy. He's perfectly entitled to his opinions on policy, I'm not going to comment on that directly. However, he does seem to think that scientific conclusions lead inevitably to particular policy choices, and I don't agree with him here. Policy is decided on the basis of a number of lines of evidence, including economics as well as physical science, and also subjective opinion and political views. That's why we have elected governments to decide on policy, rather than leaving it to scientists (or economists, or indeed any other specialist group). But because David views policy as being solely driven by the science, he tries to make a case against the policy by trying to argue that the science no longer supports the policy. Unfortunately, in doing this, he gets the science wrong and hence weakens his own case.
As the Bish says above, the worst bit is probably the headline. As Ed Hawkins says, Ed's graph does not show that the climate projections were wrong. Constraining the models with observations does suggest the upper end of the old range can probably be ruled out, but this is a reduction of the uncertainty range not a refutation (see the paper by Stott et al which includes Ed as a co-author).
We all know that journalists often don't write the headlines, so maybe we shouldn't assume David is to blame for the headline, but the text of his article does also say "the official predictions of global climate warming have been catastrophically flawed" which is simply not true.
David also talks about predictions of global cooling in the 1970s. Of course, as I've mentioned here many times, the Met Office predicted global warming in 1972, albeit with a slight overestimation, but still broadly correct.
Oddly, David also pins all his hopes on trying to disprove one specific part of the science (warming projections) whilst accepting a much less sound part of the "warmist" cause (future catastrophic impacts) as fact. He happily describes a 5 degree warming as "catastrophic" - at least, he says Myles Allen "believed the world might be on course for a catastrophic temperature rise of more than 5 degrees this century", and I think "catastrophic" is David's word not Myles's. I'm not certain, but I'd be very surprised if Myles used the word "catastrophic" - climate scientists don't usually use that word. Whatever the projections of the possible range of warming this century, this is a different question to what the impacts of this would be - and the uncertainties in those impacts are huge, as Myles himself has pointed out. I find it surprising that David buys into the idea that any particular level of warming is "catastrophic", as this reinforces the idea that high levels of warming should be avoided. In my view this rather weakens his argument against current climate policy.
Richard Betts:
This is the best criticism of David's article that I've seen. Where is the proof that for warming T > n, catastrophe is guaranteed, for any n at all?
On the other hand there are the space limits, with the Mail on Sunday still existing in dead tree form, for David and his sub-editors (who also tend to come up with the headline, with their managers). With this in mind we can't easily know if David (or his subs) were attributing catastrophic to Myles or adding it as editorial.
The con in the headline, for me, has to do with the completely unnecessary and irrational hikes in energy and fuel prices due to green measures before we know if there's any measurable probability of a serious problem and completely futile in making any measurable difference to it. I don't have any problem with that at all. But this is good critique Richard, thanks.
Richard Betts
Your criticism of David Rose for accepting the idea that a 5°C temperature rise would be catastrophic is subtle, but convoluted, and I think unnecessary.
Surely, all he is doing here (and likewise in calling the data “impeccable”) is conceding a part of the argument in order to concentrate attention on the part which he considers essential - namely the apparent falsification of predictions.
Since no-one denies that climate catastrophes, including droughts and heatwaves, happen, killing thousands, it would seem silly to deny that a rise of 5°C would be catastrophic.
Rose demonstrates an understanding of science rare among journalists by concentrating on the meaning of the data, rather than the meaning of words
A rose by any other name is still a rose ...
Same for catastrophe.
This sounds like several catastrophes to me:
Source? The Bali Declaration of 2007, signed by quite a few real climate scientists: http://www.climate.unsw.edu.au/news/2007/Bali.html
The signatories do not include Richard Betts, I am pleased to say. But it was signed by a Piers Forster, and by a few other familiar names from the field of climate alarm such as Hegerl, Rahmstof, Schmidt, and Schneider.
Mar 19, 2013 at 10:03 AM | Ryan
"At what point can the hypothesis that combustion leading to increased CO2 in the atmosphere leads to increased global temperatures be considered a failed hypothesis?"
When we see substantive cooling, comparable with the warming seen in previous decades.
We've seen a general warming trend over previous decades, with natural variability superimposed, temporarily accelerating or slowing the warming for shorter periods. The warming in the 90s was faster than expected due to AGW alone and probably had a natural component in addition to the AGW trend. If you're right, and all this is entirely natural variability (as opposed to a combination of natural variability and anthropogenic warming), then the world ought to cool again at some point.
Mar 19, 2013 at 10:35 AM | Richard Betts
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Richard,
With respect, I do not understand the logic behind your assertion "When we see substantive cooling, comparable with the warming seen in previous decades." This appears to conflict with the so called simple physics of the properties of CO2.
The so called simple physics of CO2 is that: an increase in CO2 levels inevitably and always leads to an increase in temperature. There is never no increase in temperature, there is never an increase in temperature but only in fits and stages. The so called simple physics is that an increase always, I emphasise always, occurs. Thus to falsify the ‘theory’, one does not need to show cooling; an absence of warming falsifies the ‘theory’. Surely, you must recognise that.
Accordingly in any year when CO2 levels have increased, as a matter of the so called simple physics there should be a corresponding increase in temperature (that increase depending upon sensitivity). If there is no corresponding increase in temperature, potentially the 'theory' is vulnerable' potentially it is being falsified by the absence of corresponding warming.
Thus in each and every year that there is an increase in CO2 levels and no corresponding increase in temperature an explanation (consistent with the underlying 'theory') is required as to why no increase in temperature was observed that year. This explanation may be that in that year there has been an offset by atmospheric aerosol particular matter (if that can be verified by proper observation and analysis), or verifiable changes in solar insolation etc, but an explanation is required if the ‘theory’ is to remain intact.
Of course, it may be that one cannot identify a specific off-setting cause, and in which case the 'theory' has to throw itself upon the mercy of the catchall provision, namely, natural variation. However, it should be recognised that as soon as the 'theory' is at the mercy of natural variation, the validity of the ‘theory’ is suspect and up to for grabs. This is so since it is a recognition that there are factors at work within the climate system which we cannot identify and which we do not know how they operate, the only thing is that we know that they can effect temperature changes. That being the case, potentially, each and every fluctuation in the temperature record potentially is explained by natural variation. This follows since if you cannot identify the forcing factor concerned (ie, it is merely part of the catchall natural variation), you cannot state how strong that forcing is, and thus you cannot state the maximum temperature change that can be caused by the unidentified forcing.
I would not wish to make a stab at the limits of natural variation, but if you look at Hadcrut4, between about 1860 and 1877 the temperature anomaly varies between –0.9 and +0.4degC. These large swings 9which may in part be caused by ENSO) suggest that natural variation can easily account for temperature fluctuations of about 1.5degC. If one goes back into the Paleo record much larger fluctuations are seen. Natural variation is potentially large in comparison to the small fluctuations in temperature anomaly that we are seeing in the thermometer record (and this is of course the reason why we cannot separate signal from the noise of natural variation).
In my opinion, it is an indisputable fact that natural variation can theoretically explain the entire temperature record as set out in the thermometer record. I am not saying it does, but I do not consider that any objective scientist could forcefully argue that natural variation alone is incapable of explaining the thermometer record. This view is reinforced by an examination of the thermometer record from say 1850 onwards. From such an examination one would have to conclude that there is no first order correlation between temperature and CO2; the only period when an increase in CO2 levels and an increase in temperature plot in tandem is the late 1970s to late 1990s. In all other periods there is no tandem plot, in fact there is even periods of anti correlation particularly the 1940s to late 1970s cooling. There may be some second order correlation with CO2 once other variables are taken into account such as aerosols etc, but the problem is that we do not have accurate observations, measurement and data on these other variables so one is unable to say whether if those variables were properly taken account of then there is some correlation with the increasing levels of CO2.
You say: "The warming in the 90s was faster than expected due to AGW alone". It is interesting to note that you accept that AGW could not in itself account for the rate of warming observed in the 1990s However, I consider this statement to be suspect since we do not know the correct level of sensitivity to CO2. If it was high, may be (just may be) the rate of warming seen in the 1990s is what one would expect by AGW alone. I doubt that that is the case since I consider that observational data suggests that sensitivity is so low that it cannot be measured by our existing instruments, technology and understanding. The satellite data for the past 33 years suggests that it is less than 1 and may be closer to zero than it is to 1.
Finally, I would observe that changes in temperature alone, is not even the correct metric to be measuring. It does not in itself identify whether there has been any increase in the energy budget as a consequence of an increase in CO2 levels. Until we start properly measuring the right metric, we cannot begin to assess the validity of the ‘theory’.
Richard Betts: I'd be very surprised if Myles used the word "catastrophic" - climate scientists don't usually use that word. While I don't dispute your knowledge of your friend Myles, I have to point out that *certain* climate scientists are quite fond of that word, and more. :-)
@Mar 19, 2013 at 1:45 PM | Barry Woods
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Barry
You are right to point out that the rate of warming seen in the late 1970s to late 1990s does not seem remarkable when it is compared to the warming seen in the 1860s to 1880s, or 1920s to 1940s. However, I consider that you have misconstrued what Richard Betts has said.
Richard Betts has not said that 'The warming in the 90s was faster than expected due to NATURAL VARIATION alone'. He has not suggested by what maximum rate natural variation can increase temperatures.
What Richard Betts has said is that "The warming in the 90s was faster than expected due to AGW alone". He is suggesting that AGW cannot of itself account for the temperature change observed in the 1990s.
Richard Betts is suggesting that in order to explain the fast rate of warming observed in the 1990s one has to additionally add in as a component some warming caused by natural variation to supplement and thereby increase the warming brought about by AGW,
In otherwords, Richard Betts' comment goes more to sensitivity. He is suggesting that he considers sensitivity to CO2 to be less than rate of temperature change observed in the 1990s.
Of course, this begs the question, what change was there in temperature in the 1990s? If one ignores the Super El Nino towards the end of that decade (which would appear to be an event which has nothing to do with CO2), and instead one looks at the temperature change for the period 1990 to 1997, when considering the satellite data, the answer would be that there was no temperature change at all!, The UAH data suggests that the anomaly was around the -0.1deg C during that period, and on that basis one would consider that sensitivity is close to zero.
Richard Betts
I wish.
In fact, the previous government decided to abrogate this responsibility by handing the drafting of climate legislation over to Eng Lit Grad, Bryony Worthington of the FOE pressure group. An unfortunate decision which seems to have set a precedent for single issue activist groups to become prime drivers of government policy in all sorts of controversial areas.
Err.... just a cotton pickin' minute there Richard. When you reported that Annan said Rose lied - and beefed it up a bit, you complained when I attributed it to you. Now Rose is reporting what Myles said, your attributing sentiments to Rose which he clearly meant from Myles. A bit asymmetric, isn't it?
For all those considering and discussing sensitivity, I would suggest that it is an indesputable fact that when one properly takes into account uncertainties and errors, we do not know whether it is today warmer than it was in the 1930s or even the 1880s (and as far as the US is concerned, it is probably cooler today than it was in the 1930s).
That is quite a remarkable consideration, especially if sensitivity is high.
Here is a 2009 article by Ben Pile on climate porn in the mass media, a porn generally contingent upon imminent catastrophe: http://www.climate-resistance.org/2009/09/tipping-point-for-the-climate-porn-industry.html
He has a good word or two to say there for Mike Hulme, and his previous post has a link to a video featuring Mike Hulme. Here he is in 2007 speaking in plain language such as I never know he was capable of, and speaking a lot of good sense as well: http://www.youtube.com/watch?v=XuxDkXwhtSo&feature=player_embedded#!
@richardbetts @foxgoose you're both right re science/policy relationship. Science has been asked to carry to great a burden IMO: science = x, ergo policy = y. This link has been made explicitly by politicians e.g. David Miliband in 2007: "The report...represents the most authoritative picture to date...showing that the debate over the science of climate change is well and truly over. What’s now urgently needed is the international political commitment to take action to avoid dangerous climate change." Moving from one to the other is just like turning the page.
Where science is portrayed as the be all and end all of evidence for policy, it's no wonder that it's the focus of attack for David Rose and others who object to climate policy. Not to say that the science should not be scrutinised, but it's had to bear too much of political weight on its shoulders.
"Science = policy justification" is a depoliticising move that will likely fail to keep politics out of the argument, while exacerbating the problems of science/public relations.
A number of comments have addressed the regrettable use of the word liar. I share these views. The use of this word is needlessly incendiary. It would have been preferrable to suggest that Mr Rose misconstrued what was said, or misunderstood what was said, or took what was said out of context etc. rather than to suggest that he was lying. There is only so much that can be said in a short article. Obviously only Mr Rose can clarify all of this, but I rather doubt that he was lying. Hopefully, this article will pave the way for more articles on this theme to be published which articles can go into more depth. Hopefully, this will lead to a debate of the science, and its consequences, which debate is well over due.
If there is any lie going on in this debate (I refer to the AGW 'theory') it is the failure to discuss and illuminate uncertainties. There is also a failure to properly discluss the limitation of projections. The CGM projections are often (and in my opinion not unsurprising conflated with predictions). What is the point of a projection if one is not expected to be guided by it in determining outcome of events? And, if it is expected to influence one's decision as to probable outcomes, then it is akin to a prdiction.
The problem with the CGM projections is that we have insufficient data spanning an insufficient length of time to draw any worthwhile projection/prediction and yet this fundamental point is not made clear. It is rather like measuring Usain Bolt's time over 100metres (or 200 metres) and then projecting this time to project how quickly he will run 10,000metres with a view to influencing what bets should be placed on a race against Ulsain Bolt and Mo Farah over a distance of 10,000 metres. The failure to make this point clear is not a misrepresentation but rather a fraud (legally one can commit a fraud by omission of relevant data).
Yesterday i watched the BBC2 programme on the Challenger disaster. Climate scientists would be well advised to watch that programme. The first 10 minutes was illuminating. The theme of not properly getting a grip on uncertainties and their impact was also very illuminating. I thoroughly recommend a viewing of that programme.
It is a shame that Richard Feynman's life was cut short. One can only wonder what he would have made of all of this.
warrenpearce - "but it's had to bear too much of political weight on its shoulders."
Are we sure it does not choose to "bear political weight"? How can "Policy relevant" remain separate from politics?
From the MO:-
http://www.metoffice.gov.uk/climate-change/policy-relevant
Richard Verney
I wondered how long it would take to mention the Feynman / Challenger programme! I saw it too, and read Feynman's own account of it in "What do you care what other people think" (which is even better than the programme). I do agree with him that "Reality must take precedence over public relations, as Nature cannot be fooled". I think a harsh lesson was learnt here in relation to communication of seasonal forecasts (BBQ summer!). :-)
However you can also flip it round the other way and say sceptics should also take note. Are we properly accounting for risks, and making appropriate decisions in the face of uncertainty? OK we can't be certain that climate change is extremely dangerous, but we can't be certain that it isn't either.
Richard Verney & Richard Betts
I too watched the Feynman / Challenger programme.
The take home for me was what is a failure?
Technician - "Its cracked but it has not failed"
Feynman - "The crack is the failure!"
Boy did that resonate with my observations of our present situation.
PS thank you both very much for your contributions on this thread, illuminating and thought proviking!
Geronimo raises a very good point when he says
"Penultimate question for Richard. I am assuming that you recognise that there was a MWP, and a Roman and Minoan Warm Periods. So let's deal with them. Noobody has the faintest clue what the actual temperatures were, but they were warmer. Now the ecosystem cannot tell why it's gone warmer, so will react in exactly the same way to warmth whether it's caused by extra greenhouse gases or Little Green Men. So why didn't we get the catastrophes forecast by Trenberth and his cohorts in the IPCC after the MWP, Roman and Minoan periods?"
I hope Richard Betts will respond to this. I am not a scientist but I have been round long enough to know how things work. If the world gets warmer it must be re-acting to some increased forcing. We know there were warm periods in the past. Can we assume they were caused by 'increased forcing' even if we do not know what that forcing was? If so why were there no positive feedbacks?
The simple answer is that we would not be here if climate tolerated positive feedback (on the warming side). So it seems to me to me the most amazingly unlikely claim of climate science is that there will be positive feedbacks to the 'special' forcing of manmade CO2, and it therefore follows that the most amazingly powerful evidence needs to be adduced to support this argument. And that I have not seen.
I hope Richard Betts will field this one.