From the "what were they thinking" department…
The "Physics and Society" Forum of the American Physical Society decided to open up their newsletter to a nice respectful debate on the main conclusion of the IPCC: that "anthropogenic CO2 emissions are very probably likely to be primarily responsible for the global warming that has occurred since the Industrial Revolution". From there, things went downhill quickly!
Two articles appear in the forum's July 2008 newsletter. The "pro" case is A Tutorial on the Basic Physics of Climate Change, by David Hafemeister & Peter Schwartz. The "con" case is Climate Sensitivity Reconsidered, by Christopher Monckton.
Monckton is rather … notorious … for those who follow these debates; and an extraordinary choice for a physics journal. His article has lots of formulae but little insight or competence. It did not take long for things to turn ugly.
In short order, half the blogsphere fell over themselves in triumph that the APS had reversed its long standing recognition of the facts of anthropogenic global warming; and gleefully concluded that the APS with its 50,000 strong membership could now be added to the ranks of the denialists. Fulsome praise was heaped upon Monckton's article as a brilliant mathematical refutation of the IPCC conclusions. It did not take long for the APS to add to its front page a plain statement that there had been no reversal of position; and add in red ink to the top of Monckton's article a notice that it had not been subject to scientific peer review, and drew conclusions that were in "disagreement with the overwhelming opinion of the world scientific community" and with the Council of the American Physical Society. Monckton hit back immediately with a letter demanding an apology and retraction.
How this all plays out will be most interesting to follow. The initial decision by the APS editor was extraordinarily naïve. I don't know what they expected to achieve with this; but whatever happens now it's a big win for Monckton and his fans. He's got a pulpit, and any response will be dismissed as scientific close-mindedness. Treating it as a serious debate is all that the denialists really want to achieve. Firing the editor (as some have suggested) is surely an over-reaction that would only make everything even worse.
Hey ho. I'm going to watch the social developments with interest; and attempt a minor contribution of my own just to indicate some of the errors, in my opinion, in Monckton's article.
There are, by the way, bound to be errors in my analysis as well. I'm posting it because I'll welcome feedback or corrections -- from anyone -- and because I think it is much better to focus on the substance of article, now that it has been published. I'm not an expert, but I co-incidently was reading many of the relevant papers used also by Monckton just recently, and so am willing to risk this attempt at analysis.
Basically, Monckton looks at the matter of "climate sensitivity" and feedbacks. For a useful review paper on the background to this topic, I recommend How Well Do We Understand and Evaluate Climate Change Feedback Processes? by Sandrine Bony and thirteen other authors; in Journal of Climate, vol. 19, issue 15, pp 3445-3482. (37 pages) You can also get a preprint by ftp from University of Washington Earth Observing System. It comes with a very handy little appendix to explain how climate feedbacks are quantified. Monckton also refers to this extensively.
I'll skip down to Monckton's attempt to use "The IPCC’s method of evaluating climate sensitivity".Part 1. An attempt to use the IPCC's method
It starts out ok. There is a formula used for the temperature change that should be expected for a doubling of the concentration of CO2. It is:
ΔTλ = ΔF2x κ f
The variables here, using Monckton's naming conventions, are
Monckton then correctly notes (eqn 3) that ΔF2x is about 3.7 W/m2. This follows from some basic physics, albeit obtained with difficult integrations across the spectrum and along the atmospheric column.
Everything from this point goes rather pear shaped. He makes a completely different use of the variable, to represent some kind of total anthropogenic forcing associated with a CO2 doubling, using a rather confused set of extrapolations from other effects. Basically, he takes the 3.7, scales it up so that it stands for 75% of a total forcing from other greenhouse gases, subtracts a fixed amount for aerosol cooling, and finally applies a "probability-density function" correction which has me baffled. The probability density functions for combined 1750-2005 forcings are in figure 2.20 of IPCC 4ar; It looks a bit like Monckton has taken the mode of 1.72 for the distributions by adding up best estimates for each individual forcing, and then scaled to get the mean 1.6 of the combined distribution (which is a bit skew) as given in section 2.9.2 of IPCC 4ar. Anyhow, after all of that weirdness, he ends up with about 3.4 as a forcing value; which is no longer a doubling of CO2 forcing but a strange kind of combined forcing not properly associated with any meaningful bench mark.
However, it is a forcing; so let's see what he does with it next.
His value of κ as 0.313 K W-1 m2 is uncontroversial. See the reference to Bony et al (2006) I link above.
The feedback multiplier contains more weirdness. Monckton includes a 0.25 "CO2 feedback", which is actually about the changing rate at which carbon is taken up from the atmosphere into the other reservoirs of the carbon cycle. This is discussed in section 7.3.5 of IPCC 4AR. What it means is that the fraction of emissions removed from the atmosphere reduces as carbon is being taken up and as temperatures increase; so that the same level of emissions results in a greater CO2 concentration.
This is not a feedback in terms of more temperature per unit forcing, and should not treated as such. Adding the 0.25 term is an error here, and it becomes very obvious as an error later in Monckton's article.
In any case, Monckton gets 2.16. He'd have been better to stick with 1.9; which is the actual feedback parameter. The accuracy of this number is low; certainly not enough to justify two decimal places.
The gain is then obtained as (1-2.16*0.313)-1, which is 3.077; far too many figures of accuracy. The errors in the 2.16, combined with the subtraction, mean that this number is only accurate to about +/- 1
Also, it should be (1 - 1.9*0.313)-1, which is more like 2.5.
Finally, he multiplies everything together to obtain 3.405 x 0.313 x 3.077 ≈ 3.28. Using the correct numbers, this would be 3.7 x 0.313 x 2.5 ≈ 2.9.
Monckton congratulates himself for "demonstrating that the IPCC’s method has been faithfully replicated" because his value of 3.28 is close to the central point of the range offered by the IPCC, being from 2 to 4.5.
However, what the IPCC actually says (technical summary) is:
So in fact, if Monckton had simply used the 3.7 forcing and the correct feedback parameter of 1.9, he'd have got much closer to the IPCC conclusion, and would have been following their methods.
So far, the errors don't have a lot of impact, but they demonstrate a level of basic misunderstanding that does not bode well. From here, things go downhill fast.Part 2.1 Adjusting the numbers. The forcing.
The first and major step is a look at radiosonde data for warming in the troposphere. This is a notoriously difficult area, as the radiosonde record has well known systematic errors, which have been discussed now for decades. A couple of recent papers have come out just this year which address many of the issues by using wind shear information. Specifically:
Basically, the mid-troposphere warming is indeed present, as expected.
Monckton does cite this new research, but dismisses it on the basis of satellite records... another case where measurement and calibration errors are a source of hot dispute. In any case, let it go... because what Monckton does with this is astounding.
He divides the forcing by 3. (equation 17)
That's just surreal. There's no basis to reduce the forcing here. It's the temperature response that is involved. He gives a vague appeal to Lindzen (2007), Taking greenhouse warming seriously, in Energy & Environment 18 (7-8). But that paper does not propose any reducing in forcing; only to sensitivity... on roughly the same dubious basis of limited troposphere warming.Part 2.2 Adjusting the numbers. The no-feedback sensitivity.
Here I confess to sharing a concern with Monckton. I've been looking at these papers now for a couple of months now for another discussion, and I also have tripped up on how this parameter is defined. I've been reading the same references Monckton gave in his paper (Soden, Bony, Colman etc) and I don't really get how the value of -3.2 is obtained. I can understand the -3.7. If anyone reading this would put a comment or a pointer to help clarify, I'd appreciate it!
But in any case. For this next calculation it become obvious that including the carbon dioxide feedback term of 0.25 as part of the feedback parameter b was an error. Monckton uses his 2.16 feedback parameter for a fixed CO2 forcing taken from observations. But that 2.16 included the curious 0.25 addition intended to account for changes in how carbon is taken up into the carbon cycle. It definitely can't apply here, where direct measurement of CO2 levels are being used.
There is also the bizarre use of a "mean" between two totally conflicting sets of measurements; based on NCDC, and a rather strange halving credited to McKitrick. It should be two alternative values; not a mean. And by using 1.9 rather than 2.16, you should get about 0.31 from NCDC values and 0.22 from the halved temperature.
This is not a sensible way to estimate κ, but in fact using the NCDC it gets close to the original value being used. But now Monckton is "double" dipping, in diverting the number down based on McKitrick... because this is ANOTHER reference to reduced warming trends... already used above to reduce the forcing estimate.
(Hat tip also to Tim Lambert, who notes this same error at the Deltoid blog: Monckton's Triple Counting.)Part 2.3 Adjusting the numbers. The feedback gain.
Monckton looks immediately to maximum upper bounds here; which conceals another subtle error. The various feedback parameters are not independent of each other.
In particular, the magnitude of a water vapour feedback (positive) tends to track with the magnitude of the lapse rate feedback (negative), since both become stronger with more water vapour in the atmosphere. Water both has a greenhouse effect for a positive feedback, and a weaker lapse rate for a negative feedback. You can't maximize both together; their sum shows less variation than either one by itself.
The actual range of all feedbacks together is available in Bony et al: it is about 1.5 to 2.6
There's no problem with the maximum exceeding the 1/κ value of 3.2
There's also a curious point that Monckton has already proposed a lower value for κ, which raises 1/κ to a bit over 4; but that is a detail. The fundamental error here is in simply adding up the upper bounds of feedbacks. They are not independent values; but are obtained as tuples from a range of models. Details in Bony et al (2006).Part 3. Conclusion
Monckton's paper looks superficially impressive, but examination of the equations betrays some fundamental confusion on the physics and climate science involved.
Monckton's best case here is simply the alleged lack of mid-troposphere warming. All the maths stuff is so badly flawed that it detracts from the shreds of what argument might be salvaged. The issue of troposphere warming will continue to be a focus of interest and debate; but skeptics invariably fail to take proper account of the large error bars on the old troposphere temperatures they invoke; and with the recent work on wind shear this argument, which was never strong, is looking more and more dubious.
Update: (July 26) Gavin Schmidt at realclimate has a response as well: Once more unto the bray. Gavin, by the way, is the real thing; a scientist active in climatology, and in public communication efforts, and with a daunting record of directly relevant formal scientific publication. He also linked to my little blog! Me and Gavin, yeah, that's the ticket.
Sunday, 20 July 2008
The APS and global warming: What were they thinking?
Analysis of models together with constraints from observations suggest that the equilibrium climate sensitivity is likely to be in the range 2°C to 4.5°C, with a best estimate value of about 3°C.
Feel free to use or cannibalize my Figure 7 discussion. I think it's important since over the years that graphic (produced, interestingly enough, by the State of West Virgnia's chief mining engineer) has impressed lots of people as constituting a strong prima facie case against CO2 as a major factor in climate. (Whether it really did impress Saperstein or not is an interesting question. On the face of things yes, but I suppose another interpretation would be that he was saying "More rope, Your Lordship?")
ReplyDeleteHi Steve; welcome and thanks for the comment.
ReplyDeleteHere's a link to the discussion as you provided in a comment in the Deltoid blog: comment by Steve Bloom on paleorecords of CO2 and temperature in Monckton's paper.
Just to note that the FPS in the recent past did not find it so difficult to deal with climate-related articles "outside of the consensus".
ReplyDeleteFor an example, see Gerald E. Marsh’s “Climate Stability and Policy” in April 2008.
According to Marsh, current CO2 levels are too low and contributing to climate instability, even 750ppmv could still be not enough to stop an upcoming, catastrophic Ice Age. and the IPCC should switch its focus towards “determining the optimal range of carbon dioxide concentrations that will stabilize the climate, and extend the current interglacial period indefinitely”.
There was no major controversy at the time, even if the above is not mainstream at all.
Why did the APS had to overreact about Monckton with red inks and a rebuke of the FPS editor, I do not understand. Couldn't they simply publish a point-by-point rebuttal in next issue of the FPS? Especially if to write such a rebuttal only a couple of days are needed.
Welcome omniclimate!
ReplyDeleteI think the reason a disclaimer was needed on this occasion was simply that there was such an immediate and widespread distortion of what had occurred.
Specifically, it was immediately being claimed all over the blogsphere that the APS was reversing its position, and that Monckton's article was peer reviewed, or that Monckton's article being published meant some kind of endorsement.
All the above are false; and it was quite appropriate to put up an immediate and plain statement to counter these misrepresentations and set the matter straight.
The same could have been said for Marsh's article; but I don't there was a need, since it should be obvious anyway and it was not being widely misrepresented in the same way, I think.
In my view, we definitely don't want to insist everyone must march with the mainstream. But not all maverick ideas as poorly thought out and incoherent as Monckton's article.
Marsh's article; though idiosyncratic and well outside conventional notions, and with flaws of its own, is still more competent and interesting; and was not so swiftly misrepresented all over the internet.
Why did the APS had to overreact about Monckton with red inks and a rebuke of the FPS editor, I do not understand.
ReplyDeletePerhaps because Monckton issued a press release (through an organization for which he serves as policy maestro) claiming that the APS had published his "major PEER-REVIEWED scientific paper mathematically disproving AGW in an APS JOURNAL".
Two false statements bolded there ... (it's a newsletter, not a journal as typically understood by scientists and as implied by Monckton).
Monckton's been feeding the denialsphere response with false statements. It's no overreaction to attempt to set the record straight, though it's already far too late.
In the case you cited, did the author misrepresent his work and lie about the APS ("reversal of position" crap)?
"Monckton's been feeding the denialsphere response with false statements. It's no overreaction to attempt to set the record straight, though it's already far too late.
ReplyDeleteIn the case you cited, did the author misrepresent his work and lie about the APS ("reversal of position" crap)?"
I still can't understand. Surely the whole point of a 'debate' is that you are prepared to change your position, assuming the argument is good enough?
I can see that Monckton's paper has errors - why not point these out? Instead the APS seems to be suggesting that they are having a debate, but have decided beforehand that they will NOT change their minds! In which case, why have the debate at all?
has anybody got a link to Monckton's organization "press release"?
ReplyDeleteThe first press release of which I am aware came from the Society & Public Policy Institute, on July 15, signed by Robert Ferguson, who is the society's president. Monckton is the "Chief Policy Advisor", so he is almost certainly the source of the information. The release describes Monckton's article as a "mathematical proof" in a "major, peer-reviewed paper", within a "learned journal". It apparently came out on the day the newsletter was released; at least, it speaks of "today".
ReplyDeleteSee Proved: There is no climate crisis.
Hi,
ReplyDeleteI tried my own hand at Monckton's numbers and I am not sure of what I am doing, but I think I found something weird.
IPCC gives the forward 'gain'k as
.313 C-m^2/W
and the backward 'gain'b of 2.16 W/m^2-C.
I write the loop equation recursively (.313)*(F+2.16(Tn-1)previous temp)=Tn.
Notice the +. That's because the feedbacks are positive and adds with the F. I use F=5.358*ln(C/278) for the forcing function.
Try it at 550ppm and I end up with a temperature rise of 3.5 degrees C
for the IPCC values above. Monckton quotes Hansen as reporting a temperature rise of 2-4.5 deg C with an average of 3C at 550 ppm.
Then put in Monckton's 'corrected' values of k=.241 and b=3.38 and I get a much higher number of 4.69C at 550 ppm. This is because Monckton (stupidly) INCREASED POSITIVE feedback effects from 2.16to 3.38.
In other words his 'improved' method shows much greater warming. I also tried it at 378 ppm and he is slightly higher at 1.69C than Hansen at 1.68 deg C.
I might have screwed this up but I don't think Monckton realizes that the backward loop is for a positive feedback situation(i.e. water vapor, other GHG are increase temperatures).
He was so proud of his algebraic gyrations I don't think he checked his own sums, IMO. It's also irritating that he uses K instead of C because 3.5 degrees K is incredibly cold. He also uses 338ppm as a baseline Co, but also 278 ppm
Comments?
Hi anonymous. A few trivial terminological comments.
ReplyDeleteNormal conventions in science are to measure temperature in Kelvin (K). I'll be doing that. Note that a change of temperature in Kelvin is the same as the change in degrees Celcius. Hence 3.5 K is not a "cold temperature", but a "small change in temperature", and it's the same whether in Kelvin or Celcius.
Careful of the term "gain". Gain generally refers to the dimensionless factor by which a signal increases or damps. In this case, "f" is a "gain" due to feedbacks.
The value κ is a "sensitivity" term, given as 0.313 K/(W/m^2). It is also often inverted, and indeed Monckton obtained 0.313 by inverting the 3.2 W/m^2/K provided in his references; also called the Planck feedback parameter or the Plank response, or blackbody response, or variations of such terms.
The value b is also a "sensitivity" term, for feedback. The actual "gain" is factor by by which sensitivity increases as a result of feedback, which is 1/(1 - bκ).
This gain is actually the solution to your recurrence relation for temperature. Just calculate Tinf = 0.313 * F * gain
I think you have misunderstood Monckton's argument (which is not as clear as one might like!)
Monckton reasons as follows:
1. The IPCC uses a feedback value of 2.16.
2. The IPCC uses a base response of 0.313
3. The product of these must be less then 1, or else there would be a runaway feedback, which we obviously don't have.
4. The feedback value is uncertain, with an upper bound of 3.38
5. The product of 0.313 and 3.38 is more than 1.
6. Clearly then, the upper bound is too high, and should be reduced.
7. If we are justified in reducing the upper bound, we should also reduce the central estimate.
8. Ergo; the feedback value should be less than 2.16
Clear as mud? The whole foundation of Monckton's artgument is that feedback estimate is too high, and should be reduced. Here is the big error in Monckton's chain of reasoning.
1. Actually, the IPCC uses 1.9
4. Actually, the upper bound on this value is 2.6. The simple sum of upper bounds on the individual parts of the feedback is invalid.
5. The product of 2.6 and 0.313 is less than one, so there's no problem here about feedbacks being too large.
Different baselines for CO2 are fine; it just depends on what times you are looking at. For estimating sensitivities, it's actually much better to take a more recent baseline, because if you go all the way back to he pre-industrial value there are too many other forcing factors to mess things around.
His sums are more or less okay. It is the analysis and the physics that is really incompetent.
Hi DQ,
ReplyDeleteYes, I did notice that k*b HAS to be less than 1, but I was using
his 'improved' values to show that while at lower ppm Monckton produces less temperature, at ppms larger than 378 the temperature rise is even greater than Hansen calculates. I suppose I am assuming that his new values are sincere(and wrong) and you believe they are simply bogus.
You say his sums are right but what do you get for a temperature rise over 278 ppm at 550 ppm using his formula?
Monckton quotes Hansen saying 2-4.5,averaging 3 degree rise over all, and I get 3.5 degrees using the formula and IPCC k=.313,b=2.16.
Using Monckton's k=.241,b=3.38, I get 4.6 degrees at 550 ppm.
I am interested in this because the paleological time chart Monckton shows, indicates that the average of the earths temperature 1750 was ~12 C and in the Cretaceous it was ~22 C and I believe Al Gore said recently that CO2 concentrations soon shall be as high as they were 60 million years ago at the end of the Cretaceous(~1000 ppm).
Using the formula and k=.313, b=2.16 I get a temp rise of 6.6C but with Monckton k=.241,b=3.38 I get
8.8C which is close to 10C in the chart.
Is it worth checking? (I used an excel spreadsheet.)
You are not following his argument still. Check my comment #10 again.
ReplyDeleteIf you still don't get it I'll try again; but fundamentally Monckton is NOT suggesting 3.38 as an "improved value" for b; precisely the reverse!
His argument is wrong, of course. But your criticism of it is off target as well. Read through my comment #10, especially the 8 step argument proposed by Monckton; and if it is still unclear I'll try again. The 3.38 is Monckton's notion of what the IPCC has as an upper bound on b (it isn't) and because it is too large, Monckton argues that the IPCC estimate of b at 2.16 is too large (it isn't).
Monckton is not proposing b = 3.38. He is proposing b < 2.16
It's weird on two levels; he doesn't actually carry through with a different value for b; only for κ, and the proper value for b is 1.9 anyway.
Stick with it, by the way! Taking the time to sort through the argument puts you in a great position to point out its flaws. But you're not quite there yet, I think.
I do suggest not always referring to "denialists" and "deniers". I think there are really 3 groups -- AGW supporters, deniers, and AGW skeptics.
ReplyDeleteThe AWG supporters accept the IPPC positon, the deniers deny that there even is GW.
The skeptical group accepts global warming but questions whether CO2 is the direct primary driver, and questions how much influence can be laid to humankind (the "A" part of AGW).
Hi DQ,
ReplyDeleteYes, I see that in the end he uses b=2.16.
My fault--I thought he was merely wrong and had his own data.
But I think TVMOB argues in a rather sneaky way. After all that time using all the MAXIMUM
IPCC values to get a b=3.38, he inserts 2.16 at the bottom into his estimate.
I am surprised that he uses so much IPCC generated data and just tweaks one value to 'prove' his point. He's not an 'eccentric' but
more of a charlatan.
"It is, therefore, prudent and conservative to restore the values κ≈ 0.24 and f ≈ 2.08 that are derivable from IPCC (2001), adjusting the values a little to maintain consistency with Eqn. (27). Accordingly, our revised central estimate of the feedback multiplier f is –
"f = (1 – bκ)–1≈(1 – 2.16 x 0.242)–1≈ 2.095 (29)"
Fooled me once, TVMOB..shame on me.
How very weird; to find myself in the position of defending Monckton...
ReplyDeleteNo offense intended anonymous, but given that it is my blog article that and I am highly critical of Monckton's ability to do physics, I'm going to disassociate myself from the "sneaky" notion in use of 3.38
There's nothing "sneaky" about using 3.38. The argument, such as it is, absolutely requires it. I have spelled out the argument above in a comment dated 22 Jul 16:34.
There are several fatal errors in the argument; but the use of 3.38 should be identified as an error; not as being sneaky. He gets the upper bound of 3.38 by an invalid method; the actual upper bound is 2.6. He only uses it the once, to show it would be a runaway feedback given base response of 0.313, and in context it is plain enough how it fits into the steps of his argument that the IPCC overestimates b. The argument is wrong and incompetent ... not sneaky.
His whole argument is that the IPCC numbers are invalid, and this requires him to use a lot of stuff from the IPCC and then propose a series of corrections. That's not a valid basis for criticism either; it is a perfectly credible way to structure an argument. Where it goes off the rails is not the structure of the argument, but the lack of any physical merit in its details.
Hi DQ,
ReplyDelete"How very weird; to find myself in the position of defending Monckton... I'm going to disassociate myself from the "sneaky" notion in use of 3.38"-DQ
I find using 3.38 to be sneaky because
1. He admits that these are maximas, upper estimates, not averages and you don't add up maximas to determine b. He also 'wonders' why the IPCC decided to take 2/3 of 3.38 sum of maximas.
2. Then he goes on to use the IPCC
b=2.16. In other words, he accepts some IPCC numbers and not others.
Why???
Because he uses b=2.16 to recalculate k in the previous paragraph from NCDC, McKitrick data.
"The value of κ cannot be deduced by observation, because temperature feedbacks are present and cannot be separately measured.(Is that true? Is that how the IPCC calculated k? What about IPCC'lapse rate') ....
CO2 concentrations are the annual means from 100 stations (Keeling & Whorf, 2004, updated). TS values are NCDC annual anomalies, as five-year means centered on 1980 and 2005 respectively. Now, depending on whether the NCDC or implicit McKitrick value is correct, κmay be directly evaluated:
NCDC: κ= ΔT/ (ΔF + bΔT) = 0.412 / (0.560 + 2.16 x 0.412) = 0.284 °K W–1 m2
McKitrick: κ= ΔT/ (ΔF + bΔT) = 0.206 / (0.599 + 2.16 x 0.206) = 0.197 °K W–1 m2
Mean: κ = (0.284 + 0.197) / 2 = 0.241 °K W–1 m2 (26)"
which is Monckton's new value of k.
(And he takes a mean of the two estimates?!)
Seems to be circular reasoning to me. How can k be a function of b?
You said
"His whole argument is that the IPCC numbers are invalid, and this requires him to use a lot of stuff from the IPCC and then propose a series of corrections. That's not a valid basis for criticism either; it is a perfectly credible way to structure an argument. Where it goes off the rails is not the structure of the argument, but the lack of any physical merit in its details."
No. Monckton does'nt say IPCC numbers are invalid, he uses one number b to calculate k using his data.
Monckton says he is just checking sums. The easiest way to make sums work is to arbitrarily fix them so they do and that's exactly what Monckton did.
Good post.
ReplyDeleteI also want to point out that tropical tropospheric warming is not a unique greenhouse signature, but is due to the moist adiabat...so he could just as well have concluded that the "solar signature" is missing. In the vertical, stratospheric cooling is probably the largest "GHG" fingerprint, and that is seen in both observations and models.
DQ,
ReplyDeleteGreat post, along with enlightening comments.
I can just about follow the maths, although I certainly couldn't have got there under my own steam, so nice to see others stepping up to the plate on this one.
Of course, none of it comes as any surprise that a retired politician who studied classics and journalism should produce an error-strewn and muddled 'scientific' paper.
The frustrating thing in all of this is, that no matter what flawless mathematics and science is thrown out to counter Monckton, the denial camp will dismiss it as 'Big Science Lies' or 'Censoring Debate', whilst crowing victory over this latest 'proof'. [sigh]
Oh well, keep fighting the good fight. :)
Cheers.
P.S. SunSword:
I do suggest not always referring to "denialists" and "deniers". I think there are really 3 groups -- AGW supporters, deniers, and AGW skeptics.
I think this is really only true in the same sense that we still have 'evolution sceptics'. The evidence for AGW is almost, if not already, as mountainous as that for evolution. The only serious debate appears to be 'how much' and 'how quickly'.
The denial camp appear to have nothing, other than oil industry propaganda, wingnuts and a handful of discredited scientists. If there's anything else, I've not seen it from much research and arguing with the denial gang....
We might add another word: Obscurantism
ReplyDeletefrom Wikipedia:
Obscurantism (from the Latin obscurans, "darkening") is the practice of deliberately preventing the facts or full details of something from becoming known. There are two common senses of this: (1) opposition to the spread of knowledge—a policy of withholding knowledge from the general public; and (2) a style (as in literature or art) characterized by deliberate vagueness or abstruseness.
Choosing Moncton for creating a denialist piece was an excellent idea by the APS.
ReplyDeleteAs he pulls no weight, taking apart his "analysis" in the publication will nicely illustrate the foolishness of GW Denialism.
Moncton represents the enemy of ignorance and deceit. Not responding in print to the APS is the equivalent of doing nothing while the enemy mugs your neighburs.
Take No Prisoners.
As substantive and well done as this critique is, I still can't help the feeling that this is all akin to a debate about the correct weight of phlogiston. Some models may be more elegant than others and some critiques nonsensical but none of that changes the fact that the accepted concept and predictions of warming remain weak when actually applied to the world. It is not a logical impossibility for both Monckton and the IPCC to be wrong.
ReplyDeleteI have been a lukewarmist for a long time, convinced that CO2 had to have an effect but nowhere near the alarmist scenarios if for no other reason than negative feedbacks are (a) large and harder to model and (b) currently not the most popular focus, and so (c) they would likely tend to be minimized in the final modeling product. But that understandable working bias is hardening into a circle-the-wagons mentality.
I am deeply unimpressed by wind shear modeling as a substitute for all other measures of tropospheric temperature. I am also unimpressed by relocating the "real" fingerprint to the stratosphere as a counter to misbehavior by tropospheric measurements. These smack of wishful thinking in the face of unwelcome fact.
The skeptics’ greatest weapon at the moment is the simple fact that it has not warmed at all for quite a while and AGW modelers and defenders seem to be in denial about that rather than mobilized in a scientific mode to explain why and adjust the models accordingly.
In short, I don’t care what the correct measure of CO2 forcing is if no one can explain why it does not appear to be forcing much of anything at the present time.
Great blog, by the way. Thank you.
-George Tobin
Welcome to the blog, George, and thanks for the accolade.
ReplyDeleteYou raise a number of points; which I can comment upon. I am sure it will not suddenly make you a true believer (like me :-) but it may help to see inside my head a bit.
1. You are perfectly correct that criticisms of Monckton are not justifications of the IPCC. In answering some of your questions I'm trying to take up that other half of the equation.
2. You are wrong about how modeling products work. The feedbacks are properties of the models. You can'r measure feedbacks in real life, because a thermometer cannot tell you which portion of the temperature is due to which of the many contributing causes. Feedback parameters are never obtained directly as measurements, but only by application of physical theory; which is where the models come in. Models ARE the concrete expression of theory. Every time you see mention of the size of a feedback, it is always obtained from a model. There's no other way to do it.
Feedbacks are not something which is modeled directly. Rather, a feedback is just something that happens sometimes in a complex theory. It's a way to describe what the model is doing. For example... we don't model "cloud feedback". We model cloud. Because cloud is both dependent on temperature, and influences temperature, there will be a feedback when you model it.
From our model of clouds, we infer the feedback, as a kind of diagnostic of the model, and by holding various parts of the model fixed (can't do that in real life!) you can measure feedback parameters.
Is this making sense? The "large negative feedbacks" are only known at all because they are already a feature of existing models, and they actually ARE the most popular focus precisely because they are the largest uncertainty in modeling and the largest source of difference between alternative models. The notion of "minimizing them" is pretty close to being an oxymoron. They are descriptions of what is a large part of the model sensitivity already. "Circle the wagons" notion is also an oxymoron. The uncertainty you speak of is a description of how far apart all the various wagons are.
3. On wind shear and signatures, I think you are simply unaware of the relevant theory. The major signature for greenhouse warming has always been stratospheric cooling rather than tropospheric warming, because the tropospheric warming is a common feature of other ways to force warming. Stratospheric cooling is not. There has been no shift involved here.
The troposphere is additional relevant data, of course; but I don't think there is any theory able to explain lack of troposphere warming other then denial of warming altogether. If I am wrong about that, someone tell me. But in any case the major signature of greenhouse is the stratospheric cooling rather than the troposphere.
As far as wind shear is concerned, this is pretty basic physics as well; and interestingly it is one of the major "contrarian" voices in science (Roger Pielke Jr) who was emphasizing the importance of wind shear as a way of investigating temperatures, back in 2001. This is not greenhouse you are expressing skepticism of, but physics.
4. Finally, temperature trends have natural variation. You can quantify this, by taking a regression trend line over a certain length window (five years, or eight years, or whatever) and then slide the window along a time series to see the natural variation in regression slopes. I've done this for myself. For example, take an eight year window. Since 1975, the 8 year sliding window has slopes with a mean of about 0.19 C/decade, and a standard deviation of about 0.17 C/decade (GISS dataset). It is perfectly normal to get a number of eight year periods where a regression line gives slight cooling. But with a 15 year window, the mean slope is nearly unchanged (about 0.18) and the standard deviation for slopes is about 0.06. That is, a cooling regression line over 15 years would be 3 standard deviations away from the mean, and THEN you might start to wonder. Not before.
At present, we are still in the middle of a strong overall warming trend, with a bit of natural variation which we can quantify and check whether or not if conflicts with the trend.
No conflict as matters stand. That's just the maths of it.
Anyhow, feel free to ask about anything, and be welcome.
Thank you for that detailed and thorough response. Let me respond in kind as best I can. Sorry for the length.
ReplyDelete1) My discussion of negative feedbacks was clearly clumsy. Let me try to make the point by analogy:
I worked in cancer research as a lab tech in my youth. The people I worked for generally injected a variety of commercial chemicals in absurd quantities into very small animals in the hope that a publishable event (a tumor) would occur. (It was the era of the “cyclamate” model of cancer.) The search for a list of external causes rather than a search for why the immune system fails in particular instances was the norm because (a) it was easier to gin up a result (b) those who funded and supervised were invested in that paradigm and (c) the technology wasn’t there to do much else, especially the kinds of immunological stuff that can be done today.
That is why I cannot help but see CO2 qua cyclamate—an overfocused paradigm, enormous personal / ideological investments at the top of the funding chain while the more interesting questions are about what might work against such injections don’t seem as central as they should be.
Had I not misused the technical term “feedback” my point may have been clearer. We appear to be trying to define the phenomenon as if what is injected into the system from the outside is the defining entity when the more interesting issue is what it is that (usually) keeps the balance despite such injections.
2) Actually, I was generally aware of the physics of wind shear and I had read Pielke’s comments on the recent research (he seemed a little miffed that his prior work was largely ignored). However, unless there is something demonstrably wrong with both satellite and weather balloon temp measurement technology such that they have both missed a significant warming trend, wind shear remains an interesting line of research rather than an immediate refutation and substitute for inconvenient data from direct measurements made by established methods.
3) I defer to your expertise as to what is or is not the correctly defined fingerprint of AGW but in any event, neither the cooling on top (since 1996) nor the warming in the middle (last 8 years) have behaved as generally predicted. Which brings me to:
4) Lastly, I am intrigued by your figure of 15 years as the minimum time period of significance. The fellows at Real Climate seem to believe the figure is 20 or 30 years. Lucia Lundgren at the Blackboard has been using both 8 to 10 to declare IPCC projections falsified with a lot of rather impressive number crunching (that Pielke has praised). I recognize that there are specific ‘apples and oranges’ issues here but the idea that 15-20 years of non-warming is not a problem for the models while discrete short-term events are routinely held up as proof of AGW (the old “consistent with” maneuver) seems almost disingenuous.
Thanks again for the opportunity to participate in this enjoyable exchange. It was very informative.
Cheers.
-George Tobin
Deniers, skeptics and so on...
ReplyDeleteThe expression you are all looking for has existed in English for some time. It is "people who do not agree with us".
It is normal to have different perspectives on things; but not all perspectives are equal. Some perspectives are better informed than others, and the best basis for figuring out climate matters is physics. Not medicine.
ReplyDeleteI think I understand your position okay, George. Our differences are not primarily from failing to understand each other; but because we really do have different ideas. No amount of "communication" alone will bring us to agreement. We will continue to represent to contrasting perspectives until one or both of us actually has a substantial change of mind. But that is not a precondition for your welcome here, and I'm very happy some of this has been informative.
Your current position, as I understand it, is that you are doubtful that modelers are working as objective scientists, and you are skeptical that carbon dioxide matters as much as folks like me say it does. You express yourself fairly cautiously, but this is where you are leaning, it seems. Clarifications on "feedback" or other points don't really deal with the fundamental fact that you don't actually have any credible basis for your skepticism about the significance of carbon dioxide. If you try and rephrase to avoid what was wrong with your first line of argument, you'll simply get another incorrect line of argument. No offense intended!
You now explain your perspective using medical analogies. They describe how you see the matter, but not why. (At least, I hope not! If you actually have conclusions on climate BECAUSE of medical analogies, then you have pretty much no chance of ever developing any meaningful view of the field.)
The basic physics of carbon dioxide is not in any meaningful doubt. It has a large impact, quantified as a forcing, by basic thermodynamics and radiative transfers. It is a significant part of what makes our planet a livable climate at all. Without a greenhouse effect, the surface temperature would average around -18 degrees C. The 33 or so degrees warming we get from our atmosphere follows, by physics, mainly from the effects of water and of carbon dioxide. (There is a nice readable overview at Water vapour: feedback or forcing?, at realclimate.) You can't simply allocate a fraction of the effect to each part; they work together. Water gives most of the actual interaction with radiation, with carbon dioxide giving a significant secondary interaction. On the other hand, water falls in and out of the atmosphere almost immediately by evaporation or by precipitation; the amount of water in the atmosphere depends strongly on temperatures.
The above paragraph is the substance (in overview only) of the argument. Now, I'll use an analogy. Remember; the analogy is not the argument, only a way to help make the substantive argument more comprehensible. Carbon dioxide and water work together a bit like a guitar and amplifier respectively. Most of the sound comes from the amp, plus a smaller amount from the guitar. Most of the warming comes from water. But the sound level is still determined by the guitar, because that is what actually forces the system.
To think that people are inflating the importance of carbon dioxide is, frankly, merely ignorance of the basic physics of the whole equation. The importance of carbon dioxide and the significance of having a large increase in atmospheric greenhouse gas levels is not in any rational doubt. It's in plenty of irrational doubt, and that is basically a problem of education. This is not a "debate" in the normal sense between credible alternatives. It's a particular field of science with some well established fundamentals and a lot of important open questions, which is being systematically distorted and misrepresented in public discussions by spurious arguments on the well established fundamentals.
Many onlookers are sincerely confused and don't know who to trust. I sympathize with them, but they are not struggling with equal alternatives. They are rather unable to tell the difference between good argument and bad; which is not unusual when faced with a topic in which you have little technical background.
I don't expect to persuade you to just fall over and accept my position! You are going to have to continue trying to sort out who to trust and what to believe, and why; as we all do on many topics. You remain welcome here in any case, with no requirement that you'll actually agree with me.
On your other points, quickly.
2. You are wrong about temperature measurements and wind shear. There is no "direct measurement" here that stands as a simple hard value to be explained away. There is the stock standard scientific issue of a hard to measure quantity being constrained by as much data as we can find, and with ongoing work sorting out calibrations and biases.
3. The stratosphere IS behaving as expected. Measurements fit expectations quite nicely thankyouverymuch. Whether or not the troposphere is behaving as expected depends on what measurements you are working with. There are some discrepancies; but given the uncertainties they are not as much as you seem to think; and ongoing progress to nail down the temperature record is tending to confirm the expectations from physics and measured surface warming. The biggest discrepancy with the troposphere is a set of old measurements which were distorted by a basic algebraic error by the scientists who raised the issue. Since that was fixed, the discrepancy has been comparatively minor, mostly within error bars, with a small number of scientists making a kind of rearguard case for the discrepancy which is becoming harder and harder to sustain in the light of new data.
4. My 15 year window is based on a very crude analysis method and a simple 3-sigma deviance from a simple mean; it is entirely my own analysis, done with a spreadsheet at home and some downloaded data. A 15 year window showing a regression line with falling temperatures would, I suspect, be cause to start to wonder about an additional systematic forcing effect beyond what is at work over the last thirty years. I can think of several ways that might happen (systematic effects from multi-decadal oscillations, for example) so I'd not immediately shout "disproof". The real point is to explain why an eight year slow down is insignificant. That kind of variation is part of conventional expectations.
However! If there is a real substantive difference between me and the experts, an onlooker is much safer to put their money on the experts. I am just an amateur enthusiast. I do try to form a critical opinion of my own on the whole field, by reading the professional literature and doing my own analysis on available data. That is primarily for my own benefit. You really don't have to trust the experts blindly in everything; learning about the field is another option. It's a hard option; it can't be done overnight. But it is an option.
Thanks for a blog, just discovered, which is about the only AGW advocate blog I have found with a reasonable, polite tone - and which doesn't descend into instant wholesale abuse of those who 'think different'.
ReplyDeleteContinuing the dialog about CO2 and water vapor, is it the case that what sparks the increase in water vapor is a rise in temperature? Is this right? What happens is, we have a small rise in CO2, that then produces a small rise in temp, and this rise in temp then produces more water vapor. This rise in water vapor then produces more warming, and do on, until we reach some limit to absolute level of warmth determined by other factors.
This is the positive feedback we are talking about?
fred
That's right Fred, you've got it.
ReplyDeleteThe one minor point is; you don't actually need "other factors" to stop the feedback. If you apply the "incremental" method directly, you get smaller and smaller increments which quickly vanish away to nothing; and the whole effect is a simple amplification by some factor of the initial stimulus.
You can also calculate the whole thing much more directly as follows.
The first thing to note is that temperature is driven by energy flows. We have energy flowing in from the Sun, and also being radiated back out to space. These two flows are in balance (I'm telling a little fib there, to allow us to keep it simple; mathematically we are describing the "equilibrium condition" in which the flows as in balance; generally it takes a bit of time to reach this equilibrium, but let's ignore that for now.)
The hotter the Earth is, the more energy it radiates. If there is an imbalance of energy coming in, that will heat things up until the radiated energy output is once more in balance with the input.
For every degree of surface temperature, you get another 3.2 W/m^2 of radiated energy.
However! As the earth warms up, the water vapour effect you describe (plus other effects, listed in Monckton's article and my blog post) changes, with the result that extra water vapour keeps a bit of heat within the planet.
For every degree of temperature, you get enough water vapour etc added to the climate system to result in another 1.9 W/m^2 of energy retained back in the Earth.
Now. Suppose we "force" the whole planet somehow; by adding energy at the rate of X W/m^2. As a result, the planet is going to heat up, by a certain temperature T.
We can calculate how much it heats up with this equation:
F + 1.9 x T = 3.2 x T
This says that the forcing we added (with CO2, or with reduced albedo, or with very very heated debate, or anything else) PLUS the extra 1.9 x T from the water vapour etc, must match up with the additional radiated energy of 3.2 x T
Solve... F = 1.3 x T
Or equivalently, the temperature goes up by F/1.3
Note that without the feedback effect, it would have gone up by F/3.2
That is 3.2/1.3 ~ 2.5 times as much effect. It is like an amplifier, multiplying the effect by 2.5.
The number 1/1.3, or about 0.77, is also called the climate sensitivity. It says how much things heat up for a given forcing. This sensitivity is one of the big open questions in climatology. We know it is roughly 0.75 or so. But it could be more; and it could be less. The range is something like 0.5 to 1.2, and there's a lot of work and interest in trying to determine it more accurately.
Duae,
ReplyDeleteThanks for this blog of knowledgeable people.
Although not a climatoligist I am good at math and physics and understand most of what is being said I think.
It is my understanding that without "feedbacks" the underlying energy added by CO2 is about 1/3 or less of the total temperature change predicted for doubling CO2. Therefore it seems to me the entire debate really centers on the feedbacks because they are the responsible for the majority of the temperature change.
I don't think most people understand that. It is important because the physics of the heat caused by CO2 is rarely in dispute even by skeptics I believe. I think what we all are concerned about is that we then suddenly take a fairly unquestioned number and triple the amount of temperuture change (or more) because of a "guess" with far less proven and understood physics. You admit several times that it is "impossible" to actually measure feedbacks so they are based on models.
You have to admit the models are something of a piece of "work." There are so many assumptions and unknown relationships, missing relationships potentially. The entire methodology is grossly unscientific in the sense that the stepwise approach to temperature or climate prediction is proven to be nearly impossible. Anybody reading anything about chaos theory will be horribly skeptical of these predictions. Anybody with any computer, math or science background will understand that any "model" that attempts to step and step and step iteratively producing more inaccurate results one upon another is unlikely to result in any meaningful output. There are so many examples of this it is hardly worth mentioning.
Therefore my principal problem is not whether the forcing is 0.3 or 0.6 or 1 degree or whatever. The real question is how do the "scientists" possibly justify confidence in a computer model which you admit is essential for determining 2/3rds of the entire temperature change? A computer model which anyone of almost any scientific background would be intensely skeptical of.
Mr Monckton explains why he believes the feedback is less than the IPCC. I have no confidence in any of the theories (his or others) of these feedbacks because they are not based on the same level of physics as the CO2 itself is. Monckton could be right or Hansen or others. I don't believe anyone can say at this time.
I think the scientific community should make this clear because on the one hand you have papers being written and people saying "AGW" is undeniable and then others saying that it is a hoax. I think both are right but what is really in dispute is not whether CO2 causes warming just what the amount and time period will be. If the warming is less than 2 degrees or happens over a time period of >100 years then the argument is largely irrelevant from a public policy political perspective. it is the insistence of certain scientific members that they are right and the warming WILL BE >2 degrees and in less than 100 years that is so disturbing given the shaky scientific underpinnings of such statements.
I particularly am intrigued by your use of the 15 year window to "prove" or "disprove." The problem is that we are in a 11 or 12 year period here where a trend is either flat or down. Given the lack of heat in the ocean and the unmeasurable heat effect in the troposphere and the lack of land temperature increases it is hard to see how we will get any substantial increase in the next 3 or 4 years. It seems the skeptics are almost locked into winning based on the 15 year basis. The Nature article published just a few months ago said as much. On top of that are the PDO and NAO phenomenon which appear to be reversing and we are seeing these effects just starting. Several distinguished climatoligists believe these are overriding effects and could last for 25 or 30 more years. There is the issue of the sun although I remain unconvinced there is a correlation over time that is interesting. I have no idea how the sun might affect our world (spoken a little facetiously) but I understand that the apparent variations in solar radiation seem too small to have an impact. I have wondered if the strong magnetic effects of the storms that produce spots could cause interaction with our earths magnetic field or somehow affect ionic behavior in clouds. Has anybody thought of that? Could a rapidly varying magnetic field as opposed to a slower one cause effects on climate? Possibly the atmosphere is sensitive to particular frequencies we don't understand. All I know is that there is a compelling case to be made (frankly better than the CO2 relationship to temperature posited in the past). The historical relationship of CO2 to temperature appears irrelevant to me since it is obvious that the CO2 followed the temperature rises and this was largely due to ocean outgassing most likely. The physics is totally different from what is now postulated to be occuring where the CO2 is driving temperature not the other way around.
Anyway, what bugs me more about the 15 year time window is the fact that the modelers can't have it both ways. Either their models are accurate (which they argue) in which case a 8 year divergence is unexplainable and shows some missing phenomenon from their models OR their models are inaccurate (likely) in which case their predictions for 2100 are bogus. They can't have it both ways. They can't say look how well we've fitted the data in the past to our model and claim accuracy and then turn around and immediately right after producing their model for the next 10 years fail miserably to predict a flatline.
In science it is usually predictions that make or break a theory. In 2001 the IPCC predicted a temperature trend and although their are caveats of course they failed immediately! That is very disturbing to me and typical of many computer model simulations. Very small errors in assumptions and the physics models can result in gross errors and mistakes very quickly. The fact they were able to model past data is not particularly impressive from a scientific theory point of view. I hate to put this so bluntly but it is trivial to construct many models of past behavior which all fail immediately to predict the immediate future which is exactly what happened here. Maybe the models will "pull it out" but it is not the purpose or method of science to be arguing for the least likely scenario based on a blind belief in a theory. Scientists are usually skeptical and leap on data which contradicts a theory with glee. What i see in the AGW crowd is instead signs of panic reaction, attempts to squash debate, an almost religious belief that the underlying result is correct (even if there are many holes and assumptions made). That strikes me as dangerous and scary trend in science.
Lastly I think you have done a good job showing errors in Mr Moncktons article. Thanks for that. I think though on the whole he does agree that CO2 increases temperature. His main arguments are that without tropospheric warming the apparent forcing can be inferred to be a lot less than would be obvious based on the physics but even more I think his arguments rest on the fact that the feedbacks are not proved and are subject to vast error and interpretation.
As you point out to settle the argument of feedbacks we have to look at the data. Unfortunately the data is extremely uncooperative at this time. Even assuming the troposphere data can be fixed it is hard to understand ocean temperatures falling and the lack of land temperature increases for so long. There must be something else going on here and that is the most compelling argument to me. We just don't understand well enough to make these pronouncements like we are 95 or 99% certain as Hansen does.
Lastly on the wind data to "fix" the troposphere it seems to me as a layman that there are many assumptions made in those calculations. The idea we understand all of the factors and phyiscs that affect wind with more accuracy than temperature measurements is not obvious. Maybe it is obvious to you but I read those papers and frankly they look as full of assumptions as many of the models assumptions about climate behavior. Therefore it seems highly unlikely that these are more accurate than the satellite radiosonode data seems quite non-intuitive.
Thanks for your time if you read this.
Welcome, saturn. Thanks for taking the time to give a long comment.
ReplyDeleteA comment stream like this is not a good place to carry out a debate on climatology; and unfortunately, there is a tendency for discussion keep expanding until we've covered the whole field. Comment streams are also really awkward for writing, and I don't much like the blogger comment facilities. I'm going to attempt a response to your various claims and comments; but I may not go into a long to-and-fro exchange afterwards.
I will also be very dismissive of saturn's claims. Some folks have said nice things about the tone here, and I'll try to maintain that. But don't mistake that for my having more than usual respect for the arguments themselves. I aim to look carefully at all arguments on their own merits; but not because I'm undecided. It's just my preferred personal style, and it is the foundation of my confidence that AGW-skepticism arguments are profoundly irrational and riddled with misunderstandings of the science.
The heart of the problem of what word to use for the AGW-skeptics is that their arguments are so dreadfully bad. Any word used by people who actually understand the science of climate will tend to carry disparaging connotations. And so it should. This is not merely a matter of being rude or disrespectful. It is a well informed opinion on the standing and merit of arguments being used by the AGW-skeptics.
So saturn! – welcome to my corner of the web. I'm glad to have you here, and I have no expectation or demand that you will change your mind and accept my position. I include here a point by point response, which can stand side by side with your comment, and readers can see both views, to check out further for themselves which one is more sensible. There's no aggression here to you personally, and you are welcome.
(1) Saturn says: "the entire debate really centers on the feedback". That's not a bad summary, if you want a one-line summary of the big issues in a large field. The feedbacks can be quantified as something from 1.4 to 2.4, centering on 1.9. This is what Monckton calls "b". The real science and the genuine open questions are involved in trying to constrain that number. There is a large body of good solid scientific work applying theory and empirical observation from many different lines of investigation to give the currently known constraints, and ongoing work continues to chip away at the problem. In the meantime, irrational skepticism is thinking it is closer to zero; or that because it is unknown it means we can dismiss all constraints of any kind already discovered by science, or that because it is complicated the scientists who are studying it must be guessing, or incompetent. Nonsense.
(2) Saturn says: "You have to admit the models are something of a piece of work." In fact, I have to admit no such thing. The models have contributed enormously to understanding; and they continue to be refined and improved in various ways. But you don't need complex climate models to get the basic facts routinely denied by AGW-skeptics; such as the fact the planet is warming up, and the fact that the major cause of warming in recent decades is greenhouse gases in the atmosphere. The models are rather the concrete expression of all the relevant physics of thermodynamics and chemistry and fluid flow to try and constrain the details. Along the way they have confirmed the straightforward fact of AGW, but that is secondary. There's a long way to go in the whole modeling area. Cavalier dismissal of all the progress that has been made is irrational; and the implication that it is all based on unreliable climate models is false. The main facts of AGW follow from measurement (for warming) and the physics of radiative transfers (for the critical role of greenhouse gases).
(3) Saturn says: "The entire methodology is grossly unscientific in the sense that the stepwise approach to temperature or climate prediction is proven to be nearly impossible." This is flatly false; the remark has no foundation in chaos theory or anything else. The methodology is routine science, used also in all kinds of other fields without qualm. One of my favourites (I love astronomy) is the detailed physical modeling of a supernova explosion. The methodology is the same; the difficulties are similar, both deal with chaos and use stepwise gridded simulations, and the science is cutting edge.
Don't get me wrong here – projections of climate models are inexact and there are all kinds of aspects of climate that they have lots of trouble with. There is a lot of work involved in validating their results, and quantifying their inaccuracies, and extending their scope. Projections can't simply be the readout of a model. Model-based analysis results in a range of possibilities and likelihoods. But fundamentally – the range of legitimate uncertainty cannot possibility encompass the extreme skepticism of those who deny AGW.
(4) Saturn says "I particularly am intrigued by your use of the 15 year window to "prove" or "disprove." I think you are reading too much into this. I ran a very simple naïve analysis – which is all you need to show the basic error underlying AGW-skeptic claims that warming has stopped. An eyeball of the temperature graph shows that there's a strong warming trend since 1975, and that the trend is not uniform. A bit of maths shows that the recent slowdown is well within the natural variation that is easily visible in a plot of measurements.
(5) Saturn says: "Given the lack of heat in the ocean and the unmeasurable heat effect in the troposphere and the lack of land temperature increases…" All the various claims about measurements and distinguished scientists and what not simply do not match up with what is going on in the literature. Claims of oceans cooling, and troposphere cooling, are particularly egregious errors. Both are founded on cherry picking old papers with surprising results, and including errors discovered since publication and recognized even by the scientists who made the original claims. There's still ongoing debate and cleanup of the details; but the main "cooling" results from a few years ago were just wrong; though they do get recycled indefinitely in the popular debate. The land temperature thing is fluff; land temperatures are still increasing, more strongly than the sea temperatures, as expected.
(6) Saturn says: " The physics is totally different from what is now postulated to be occurring where the CO2 is driving temperature not the other way around." No, the physics is exactly the same. What's different are the circumstances to which the physics is applied. The physics, in both cases, tells you that CO2 has a significant warming effect; and that CO2 exchanges between atmosphere and ocean. The current circumstance is a huge increase in CO2 from geological reserves (fossil fuels), all over a very short period of time. The physics says that the ocean will take up a lot of this CO2, but gradually. (Confirmed; something like 40% of human emissions have ended up in the ocean already, making it more acidic.) The physics says the atmosphere and surface will warm up. (Confirmed; measured.) In the ice ages, the physics says that rising temperatures reduce the solubility of CO2, resulting in a transfer from ocean to atmosphere. The heating effect of that extra CO2 then gives a positive feedback to heat up even further; and this additional heating is essential to explaining the temperature cycles in and out of ice ages. Basically, in the ice ages CO2 acts as a positive feedback over a scale of hundreds of years. In the present, CO2 acts as a forcing thanks to human transfer from geological reserves to the atmosphere. Physics is precisely the same in both cases, and the study of ice ages stands as an independent confirmation of that physics, and also as a useful way to estimate the climate sensitivity… the same as point number (1) above.
(7) Saturn says: "Either their models are accurate (which they argue) in which case a 8 year divergence is unexplainable and shows some missing phenomenon from their models OR their models are inaccurate (likely) in which case their predictions for 2100 are bogus." This omits the obvious. The models are accurate for capturing trends, and also the kinds of variation you should expect around a trend. The 8 year divergence is precisely the same kind of variation seen in the models.
Models don't just give a sequence of temperatures. They give many sequences; obtained by repeated runs with small changes in starting conditions. Have a look at What the IPCC models really say (realclimate), or the diagram in FAQ 8-1, page 600 of the IPCC 4AR on the scientific basis. Analysis of model results allows you to infer a trend, and a level of natural variation about the trend. The models are not perfect; but in fact they do pretty well in capturing current and historical records, and the 8 year divergence is precisely the same kind of natural divergence that also shows up in the models.
----
So, in conclusion: the AGW-skeptics often complain that they are treated with disrespect. I want to avoid that; but on the other hand the actual arguments here are pretty much worthless. Any consideration of such material on its own merits will come across very dismissive and disrespectful indeed, and rightly so. Arguments don't have a right to respect in the same way as people; and the arguments repeated by saturn are dreadful. They carry no impact at all in the scientific world, where their flaws stand out immediately, and they serve only to muddy the water in popular debate.
I don't doubt saturn's sincerity, and I don't actually expect him to be convinced by my response. It can be really hard to sort out these matters; and I understand and sympathize on that difficulty. Here is my response in any case.
My question then is a very simple one. We know that in historical times there have been temperature rises of the same order as those that occurred between 1975 and 2005. So why did they not lead to this feedback and further warming effect? And what brought them to an end and caused the subsequent cooling periods? Like, the Roman warm period, and the MWP is what I'm thinking of.
ReplyDeleteLogically it would seem you have to argue either that there was no such warming and cooling, or that the feedbacks did happen but we did not know... or that the warming was somehow different in its effect on the feedbacks... or? But in any case, the question remains, what brought about the previous coolings?
Fred
They did have feedbacks in the same way then, as now.
ReplyDeleteFeedback is nothing more than a way of representing all the ways in which temperature responds to energy imbalances. Water evaporated in the past just like it does now; that's feedback. The Earth warms, and cools, in response to changes in energy balance in the past in precisely the same way as it does now.
I'm trying to guess why you think this is a difficult question. I'm not sure, but perhaps you think feedback means that there has to be some sort of infinite loop and unending increase. That's a special and unusual kind of feedback which doesn't apply here. There's no runaway involved.
Thanks so much for your response.
ReplyDeleteI think you have confirmed that there really is little difference of opinion about the basic physics of CO2 heat capture. It really bugs me to see either side engaging in politics because I feel it really cheapens science. One of the things that attracted me to your blog was it appeared to be knowledgeable people willing to consider everything. So, I found your mean-spritited comments about "skeptics" to be disheartening. I would expect scientists to engage in debate and to discuss the facts as you did with Moncktons paper rather than the debate shutting approach of many.
Frequently when I am trying to squash a bug in a computer program talking to someone who knows little about the subject is helpful because they make me think about things in ways I never did before. So, I find the dismissive nature of both sides in the debate to be unhelpful and dangerous to science. If the public perceives that science becomes too political and not about truth above all else then all science will suffer a huge death and damage. We need to be able to be honest about what we know and don't know because the future of science hangs in the balance. I am very worried that scientists have put us all into a black hole where the collapse of the AGW hysteria will come back to haunt every scientist and produce recriminations and disbelief of scientists in the future. It is now clear to me we are very possibly not going to see a 2 degree increase by 2100 and when the general public becomes aware of this they will be mad and we will all rue the day Lord Hansen got up and said he was 99% certain bla bla bla....
It seems we agree the feedbacks are the most important point of contention. Unfortunately in this field it is impossible to go back and know with certainty much past data. I am not saying there is not some rock solid numbers but much of the temperature record is in dispute for instance. We have only a few proxies for much of the data. For instance sea temperatures were measured by leather buckets, insulated buckets, engine inlet temperatures and any combination of the above for most of the last century. While we might have data on temperatures in any one region knowing if those temperatures were common across the globe is unknown or unknowable. We have clearly had periods of warm and cold that are scary in their severity compared to current times. What is obvious then is that there must be factors that drove all those variations and until we understand these factors it is impossible to make predictions with confidence about the future because we simply don't know what other effects that have affected temperatures in the past will recur. All such predictions would have to be caveated with: "well, unless we get a volcano of a certain size or unless we find that the sun has a massive corona or we don't get hit with a comet or whatever we can't predict or know." That is not to say that there is no value in predictions but one thing I found disturbing from the first time I read the IPCC 3 reports was that they specifically excluded volcanoes from their models of the future even knowing that volcano eruptions are common and happen 1 or 2 times a decade. A quick examination of the record shows these occur frequently and with huge impact on climate to the downside. Why didn't the IPCC factor in a fudge downward to take into account an assumed volcanic activity for the century? They fudge everything else in the models? This is not a putdown but simply fact that there are many fudge factors and assumptions of initial conditions or other parameters.
This is simply the barest foot in the door of the problems with the IPCC methodology. Reading the reports is very discouraging because so much is obviously assumption. Nonetheless as you point out it is a working hypothesis and working models are getting better and better. Nobody wants to stop the process from improving. Knowing the future climate is clearly a very good thing to know. I personally am more interested in knowing this to predict and prevent any declines in temperature in the future not to prevent increases. It is very clear to me the damage from decreasing temperatures is order of magnitudes larger than increasing temperatures.
How do we get to a common basis for models and computer simulations? I remain profoundly skeptical. I am skeptical for a huge number of reasons. 1) the programs could be simply programmed wrongly. What is the quality control process the groups use? Who does the code review and what are the ways they use to check they work? 2) how do we know the models are stable? Almost all computer models will eventually show asymptotic behavior with some inputs. It is the nature of the mathematics input into the stepwise process that can't understand every physical thing that happens to limit things. For instance, the models have to be started with initial conditions that aren't based in real numbers determined from experiment. The models produce bizarre results like the entire atlantic ocean freezing into a solid chunk of ice all the way to the bottom. This is an artifact of the fact that the models don't understand all the physics. 3) the models make assumptions about how everything interacts that are unproven. Each of these interactions needs to undergo its own intense study and vetting and quality control and yet there may be interactions we simply don't know or understand. 4) the whole idea of iterative model production is flawed since every iteration will produce results that are in error, the errors build upon one another till the end result is meaningless. This is why the error bars on the models results are truly closer to +13 degrees to -10 degrees for 2100 instead of the +2 to +4 degrees commonly bandied about. Even the modelers admit that the models cannot be used for prediction. They are sensitivity analysis tools to help identify what happens if you change one parameter what affect will this have. The modelers themselves would not be so bold to suggest that they know what the temperature in any region of the world will be in 10 or 20 or 30 years let alone 100.
This is just the barest start of the problems with the models. The point is not to debate each of these points but to point out that the physics and surety of the models is WAY more suspect than the underlying physics of IR capture by CO2. Since the models are responsible for predicting the vast majority of the suspected heat increase for 2100 it means that it is impossible to say that we are 95 or 99 % confident in our results or that the physics is proven or the kind of political poppycock that Lord Hansen goes to congress and says. It's simply impossible to be a scientist and claim such knowledge given the state of the models.
What I am saying about the current predictive failure of the models is not controversial. Many IPCC members including the lead author of the feedback chapter has already concluded that the results need to be modified substantially. Some think it won't be that big an adjustment but it is clear that the response of the enivironment to large increase in CO2 (a 10% increase in one decade) has produced NO increase in temperature in any way anywhere, neither in the troposphere, the land temperatures or the ocean. In fact buoy measurements of ocean temperatures from 2003 to 2008 are DOWN. This is not archaic information as you implied. The most recent buoy measurements from the ARGO buoys are down for 5 years. This is why the German science team got a peer-reviewed article published in nature predicting no temperature increases for 10 more years. This means that your 15 year time window is gone. We will almost certainly get a 15 year flat or down period which seriously degrades the models accuracy.
As scientists we must always be skeptical of our theories. The mere idea that "skeptic" is a bad word in science or that science is some kind of "religious edifice" that we all must defend current theories to our dying breath or something is absurd. Science is about truth and the next piece of data and any theory can become trash overnight to that truth of that measurement. The lack of a Higgs boson will be crushing for physics and most of the current theories. We may discover in the next year if physics itself is under massive change again. We don't see physicists running around saying those who don't believe in the Higgs Boson are unscientific or "evil-skeptics" or something. So, it is absurd to read that people have so much confidence in a theory of climate with so little solid information, so little proof, so little predictive ability. Please don't insult science by trying to imply we know more than we do. We have theories of climate change and climate prediction. Some of them seem better founded and provable and predictive than other parts but we are certainly not in the position to proclaim we understand the problem to a 95 or 99% certainty. Such proclamations scare the dickens out of me because of the very high probability we are wrong given our track record.
The very minimum to establish a greater degree of trust in the models and the feedbacks and AGW in general is to be able to explain the current 8 year, 10 year lull more clearly. I was very comforted by the idea we understood how particulates either from man-made pollution or volcanoes modified temperatures in the 20th century. That is very impressive. Until scientists can explain with more understanding why the last 10 years have been flat or down it is simply irrelevant that the data fits within the error bars. That's not good enough for us to believe in the theory and models with confidence. We must understand why the very first predictions of the models are immediately wrong and so badly off. Yes, they may come back into alignment. Yes, the error bars are big enough to accomodate a few years divergence but it creates enormous doubt about our ability to predict and the more protestations I hear and attacks at skeptics doesn't help. It only makes the science look cheap and unsure.
>6) Saturn says: " The physics is totally different from what is now postulated to be occurring where the CO2 is driving temperature not the other way around." No, the physics is exactly the same. What's different are the circumstances to which the physics is applied.
ReplyDeleteI think you misunderstood me. I agree with most of what you wrote in your reply to me including this part. All I was saying is that CO2 went up previously after temperatures went up and i agree we know why that happened. I have seen people point out that CO2 levels were consistent with the temperature at the time but the temperature appeared to get that high without the CO2 input. That makes one wonder why didn't the temperaure double soon after the CO2 increase happened? If the temperature was up 10 degrees 100 million years ago and we see that 500 years after the temperature jumped 10 degrees that CO2 climbs to 20 times current levels then I would expect ANOTHER 10 degree surge because of the additional CO2. Obviously the feedbacks in this case were negative to the CO2 input. Not only that but temperatures managed to fall precipitously even though CO2 did not decline. If anything the historical data seems to imply that some kind of feedback is essentially negating the effect of CO2 even when CO2 levels are 20 times higher than todays. This simple analysis should have led scientists to be skeptical of the positive feedback coefficient values in the current models or to at least propose models with much less positive feedback.
> (7) Saturn says: "Either their models are accurate (which they argue) in which case a 8 year divergence is unexplainable and shows some missing phenomenon from their models OR their models are inaccurate (likely) in which case their predictions for 2100 are bogus." This omits the obvious. The models are accurate for capturing trends, and also the kinds of variation you should expect around a trend. The 8 year divergence is precisely the same kind of variation seen in the models.
Do the models understand the PDO and NAO phenomenon? I have not seen that. I believe they think they have the physics in the models to simulate the PDO or NAO phenomenon but it is not clear to me they actually can model these phenomenon. That is important because of course these are on a current trend to decrease world temperatures and the arctic in particular over the next 25 years. The climate models are predicting behavior counter to what we have observed for over 100 years in the NAO and PDO phenomenon. Frankly, as many people have pointed out a large part of the trends since 1975 can be explained by any number of models including the PDO and NAO phenomenon which aren't scientific theories but still explain the data as well as the models especially if one considers the last 10 years. It is trivial to construct thousands of models which fit past data. This is a mathematical fact. Especially given the lack of solid data and error bars that are apparently assumed to be sufficient. I saw one paper which showed that a simple flat line linear model of the last 25 years was more accurate than all 22 models considered in the IPCC report AR4 or even the average of all 22 models. So, constant emphasis of how good the models are at simulating past data is not convincing. I continue to be amazed at how supposed smart people continue to make this error. It is not hard or surprising that people can create models to fit any arbitrary set of data to any level of accuracy desired. That is a trivial mathematical exercise. The fact that the models are complex doesn't make them any more convincing.
As I said the fact that the models predict past behavior "very accurately" is not good because it then makes it very difficult to explain their current misalignment.
There is a conundrum here which I am not exploiting. I understand that in order to get better models we need to keep iterating and there will be errors and improvements. I am simply saying that it is not understood by the general public that the vast majority of the "climate change" predicted by the IPCC and AGW enthusiasts is not based on solid physics that is proven but is instead based on largely very unproven and quite problematic models that have failed to predict very well the future.
From a scientific point of view it is only relevant what they predict for the future and they are divergent at this time and unlikely to converge anytime soon given sea temperatures as the German science team pointed out. We are almost certainly in for a 15 year haitus or more in temperature increases, maybe 20 years if the germans are right. This means almost certainly the models are wrong. I don't see the point of belaboring this point to death and defending to death something which is bizarre to defend. These models are incredibly complex and undoubtedly filled with huge numbers of errors and misconceptions and missing factors. To defend them is pointless. What we need to understand is why they are wrong in the last 10 years specifically and correct and see if we can do better.
All of this makes the projection of 2 degrees by 2100 incredibly problematic because it will require a very steep slope of temperature increases after 2013 or so to get to 2 degrees or more by 2100. Such a slope is unprecedented even in the 80s and 90s. Even if we repeated the temperature spikes of 1910-1930 and 1980-2000 over the rest of the 21st century without any more "unexplained pauses" and the NAO and PDO phenomenon disappear we wouldn't get 2 degrees. In order for us to get to the predicted (low end) of model behavior by 2100 we need to see an unlikely and unseen before temperature increase pattern. Maybe you believe that and maybe it will happen but it is not the purpose of science to make leaps of faith.
It is clear that once the models are modified to represent new data and are reset to new current initial conditions that they will not show the 2 degrees by 2100 previously calculated. Let's hope the new models work better and at least get a better start than the last batch. Let's hope we can explain to the public in a rational way why we were wrong about 2 degrees. It just doesn't seem likely anymore let's face it sooner rather than later or the damage will be much worse if we let people like Hansen go out there and tell people we are 95% certain when we aren't. He is attacking science really by making such claims.
This is about the point where I start to give offense; which doesn't bother me. It seems to be an inevitable response to the basic conclusions, no matter how carefully expressed. So be it. I will not be giving a comprehensive response to all the above by saturn, but will make a couple of basic points. As always; no offense is intended, but some of this will be sharply critical, as is appropriate. You need to wake up to yourself, saturn, and no-one likes to be told that. I sympathize, but sugaring the pill is not doing you any favours.
(1) This IS a political debate, as well as a scientific one.
Complaints that engaging in politics cheapens the debate are naïve, and usually hypocritical. The conclusions of science on this issue have important political implications, and it is right and proper for scientists, like any other responsible citizens, to get involved in politics and decision making.
Responsible decision making is guided by the analysis of risks and costs, and that is informed in turn by science. In turn, governments can and should give support to research guided at least in part by what research questions are of political and social importance.
Where this goes off the rails is when support is given to research guided by the answers desired for political reasons. Political considerations should have no part whatever in the conclusions obtained. The whole point of having scientific investigation is to get useful answers to basic questions which are NOT distorted by political desires for one answer over another.
In the present circumstance, the distortion is almost entirely in one direction only. There is a flood of the most appalling scientific gibberish being dressed up as a cheap parody of real science, intended to support outright pseudoscientific nonsense on climatology. It's not happening in reverse on anything like the same scale. The scientific community in general shows the same high standards seen throughout the practice of science, and those actually working on the subject come down in a solid block to recognize the basic reality of anthropogenic global warming.
(2) This is not a debate between equivalent alternatives.
Many people are sincerely confused about who to trust; and there is a lot of pseudoscientific nonsense being actively spread about by non-scientists and pundits with grotesquely inflated claims of expertise, and – tragically – a tiny handful of scientists who have prostituted their scientific integrity for whatever reason. At the same time, there is also a vibrant scientific debate on many questions which remain wide upon and a focus of ongoing research, and also a few fairly extreme scientific mavericks; who as always remain an important part of the whole scientific enterprise.
People with no background in the topic may find it hard to distinguish the pseudoscience from the legitimate division of opinion on genuinely open questions. They may find it hard to distinguish legitimate but isolated maverick ideas from well grounded basic conclusions. I sympathize… but we are not all in that same position of confusion, and I make no apology for declaring that up front.
It is easy for anyone with a little bit of background in the relevant science to see the flaws in a paper like Monckton's. The more background you have, the more the flaws are obvious. Merely pointing out the errors dispassionately, without any whiff of personal criticism, is a terrible idea. An important part of the message for the general public is that Monckton's paper – and many others of that ilk – is not any part at all in the legitimate scientific debate.
I personally think it is important to pull out the flaws and show precisely where they are wrong, as a part of showing that Monckton's paper is not rejected simply because of his history or because we don't like his conclusions. The paper itself, on its own immediate merits, is dreadfully incompetent. Showing this is important for the sake of sincere non-experts who want to know why Monckton is treated so derisively by the experts.
Many others will simply say "Not Monckton again" and not even bother to look at the argument. They are RIGHT to do so.
(3) Yes, we really are sure about anthropogenic global warming
Much of saturn's article just reiterates the same confusions I addressed previously. He's flatly wrong about there being a big problem about recently cooling, or about predictions being substantially off. I have already explained that models include the expectation of natural variations; and that the recent slow down is well within normal variations as both seen in the past and as predicted by models.
The oscillations of NAO and PDO are oscillations. They are part of natural variations and cycles. They are one of the areas of active open research and investigation, and they are not at this point predictable with any level of confidence. It is pseudoscientific nonsense to take that as a sweeping refutation of model based research; because we already know that models have limited accuracy, and we already make conclusions with substantial confidence bounds that take into account what is not well known. Model simulations already show lots of variation analogous to major oscillations in the real world. Saturn may be sincerely unaware of that, but there you go. That's precisely the problem. It's not easy for a novice to distinguish the genuine open questions from the pseudoscientific distortions of those questions.
(4) Claims that new data is disproving the models are flatly wrong.
Take a look at saturn's last paragraph: "It is clear that once the models are modified to represent new data and are reset to new current initial conditions that they will not show the 2 degrees by 2100 previously calculated. Let's hope the new models work better and at least get a better start than the last batch. Let's hope we can explain to the public in a rational way why we were wrong about 2 degrees. It just doesn't seem likely anymore let's face it sooner rather than later or the damage will be much worse if we let people like Hansen go out there and tell people we are 95% certain when we aren't. He is attacking science really by making such claims."
That is just arrant nonsense from someone who is perfectly obviously a total novice at the topic. It starts out by expressing considerable confidence ("it is clear