Discussion > Reacting to AR5
You don't have to believe anything - you can check it all out for yourself!
I have Masters level qualifications in Chemistry, with a decent amount of physics and maths. What you are asking me to "check out for yourself" is largely above my head. It's a long, long way above the heads of most people.
So they rely on graphs and official pronouncements. Which is where the AR5 has shown the scientists at their most scummy. Plotting 10 year blocks to hide the recent halt, and moving the starting points down so that a "mistake"(conveniently only recently spotted) can cover the obvious lack of predictive skill.
Richard Betts: if the IPCC scientists came out and showed singly each model run compared to actual temperature (based on current CO2 levels mind) as Professor Brown has suggested at CA you'd be laughed at. Such pitiful misses would be strikingly obvious. You are too scared do. And with good reason.
In order to win the general populace our best method is to 1) point out the graphical fiddles, and 2) plot them correctly.
(For the record I have followed as much of the science as I can. As chemistry-trained the obvious place is the carbon cycle. The "Berne model" -- whereby a pulse of CO2 is deemed to remain in the atmosphere for thousands of years, despite several fast equilibria in action -- was what triggered me to scepticism. It's so amazingly shite that it boggles the mind that anyone can believe it. It has to be true, of course, because without it alarmism simply melts away. No-one will worry if a couple of decades of lower CO2 use will return the system to close to the starting point. So I can see why the IPCC endorse it. What I can't see is why any chemist would.)
Mooloo
The post & comments at CA, linked to above, also makes the point that it is reasonable to expect that the actual data used to plot an IPCC graph should also be made available. The person who creates the graph has the data in a file. It is not much work to include the data along with the graph.
michael hart
Richard Betts,
This is copied across from the "First Fiddle" thread.
The graphic you link to states that the surface temp data was baselined on the 1961-1990 mean, but doesn’t actually say that that’s what they did with the projections too. In fact, it appears that the projections were based on 1990 in the same way they had been in earlier ARs. See:
Figure 1.1. Yearly global average surface temperature (Brohan et al., 2006), relative to the mean 1961 to 1990 values, and as projected in the FAR (IPCC, 1990), SAR (IPCC, 1996) and TAR (IPCC, 2001a). The ‘best estimate’ model projections from the FAR and SAR are in solid lines with their range of estimated projections shown by the shaded areas. The TAR did not have ‘best estimate’ model projections but rather a range of projections. Annual mean observations (Section 3.2) are depicted by black circles and the thick black line shows decadal variations obtained by smoothing the time series using a 13-point filter.
I could find no discussion of what was done on this graphic in the relevant chapter either, but perhaps I missed it. Do you know where this was discussed? Also, wouldn’t rebasing the projections onto the 1961-1990 mean throw out the hindcasts? Wouldn’t they all be running too cool?
Laurie Childs
Richard Betts
It is totally irrelevant to state that an AR4 methodology used in a prediction/projection of future climate was not as good as a method now available. The objective is to compare previous predictions/projections with observations. Until your last post I was willing to believe that you were well meaning but wrong. Now you are trying to defend the indefensible and you lose any respect from me.
Dung
Richard Betts
Thanks as usual for taking the time to reply.
I'm afraid I stick by the word 'obfuscation'. Unless the IPCC is not interested in making its findings clear to reasonably educated laymen the graph we are referring to is a classic piece of just that. No-one other than what I might (I hope) be allowed to call a "science anorak" is going to understand spaghetti graphs but what we do understand, especially when two people have been kind enough to provide animated gifs, is manipulation.
One of those two graphs is w-r-o-n-g. I can't see any other way to describe it. The original, which appeared to show a certain amount of "inconvenient truth", to wit that the climate is refusing to behave as the models have determined it should, has been replaced by one which shows that after all everything is going along just as you all predicted it would.
I don't see how you can reconcile the two.
And quoting the model output is becoming less convincing in any event.
For the benefit of those who may not have been to the Climate Audit thread, let me quote Professor Brown
The variations between GCMs are not random variations. They share a common structure, coordinatization, and in many cases similar physics similarly implemented. The mean of many runs of INDEPENDENT GCMS is not a statistically meaningful quantity in any sense defensible by the laws of statistics. The standard deviation of that mean is not a meaningful predictor of the actual climate. One can average HUNDREDS of failed models and get nothing but a very precise failed model, or “average” a single successful model and have a successful model. So to present such a figure in the first place is utterly misleading.In simple terms, your models all share certain basic parameters; they are all wrong; averaging their output gives a very precise figure .... which is still wrong!
The climate for the last 15 years has refused to follow the path laid out for it; it is following (at the moment) a path consistent with the 60-year cycle which we know has existed for the last 160 years (which may not be very long but is still 130 years longer than the period of accurate readings of Arctic sea ice and that appears to be enough to "prove" we are all doomed!).
So far it appears that the IPCC is determined to conceal the "hiatus" and its possible implications and do everything in its power to convince us that things are still as bad as ever, that we're just imagining that warming is "on hold" and that "the models" and "the science" still say that it will start again tomorrow or next week or next year .... even though it hasn't really stopped in the first place.
If that is not obfuscation and misleading then I don't know what it is.
Mike Jackson
(For the record I have followed as much of the science as I can. As chemistry-trained the obvious place is the carbon cycle. The "Berne model" -- whereby a pulse of CO2 is deemed to remain in the atmosphere for thousands of years, despite several fast equilibria in action -- was what triggered me to scepticism. It's so amazingly shite that it boggles the mind that anyone can believe it. It has to be true, of course, because without it alarmism simply melts away. No-one will worry if a couple of decades of lower CO2 use will return the system to close to the starting point. So I can see why the IPCC endorse it. What I can't see is why any chemist would.)
Oct 2, 2013 at 2:07 AM Mooloo
I too have similar objections to the so-called Bern model, although coming from a different background. Having studied the analysis and synthesis of passive resistor-capacitor networks (mathematically the same as box models of CO2 interchanges) the physical impossibility of the Bern model's impulse response jumped out at me. It's yet another unvalidated model in climate science's repertoire of unvalidated models.
Martin A
Here we go again. When our last set of predictions proved to be shite, we just say "oh, but our current models are much better."
This is the standard patter of every con-merchant in recorded history. Please keep throwing good money after bad. The pot of gold is just over the horizon. Your gorgeous, amorous Russian bride just needs a few more thousand to get her mother urgently needed medical treatment. Etc.
Sheesh!
johanna
A brief follow-up to my reply to Richard Betts yesterday.
Richard has claimed that the "new" diagram we have been presented with complete with its spaghetti is more accuratwe than the old one which shows observations falling outside the envelope.
I am taking the view that whether or not he is correct is irrelevant and that the presence of these diagrams neatly demonstrates a fundamental problem with climate science linked to our old friend the "anomaly". Somebody made a similar point yesterday but I can't find the comment (nor even remember whether it was here or on WUWT or Climate Audit!).
Without accusing anyone of cherry-picking, it is obvious from what Richard says that there are numerous ways of handling the data which are likely to give different results. Whether any of these ways is "better" or "more accurate" or as Professor Brown has suggested "more precise but just as inaccurate as before" is a matter for debate.
As johanna says, you cannot bury your past errors under the excuse of "but we do it much better now" just because there is a way of interpreting/manipulating/torturing the data that suits your case.
Something that came to mind last night was a line from the film 'Battle of the River Plate' where Dove is claiming that his ship was inside the three-mile limit when it was sunk. Langsdorff's reply is "you want the chart to prove you right, while I ..." and he doesn't finish the sentence.
The constantly moving anomalies, base periods, and statistical practices which appear to be the tripod on which climate science is built give more than ample opportunity for the sort of "interpretation" which allows for what I have called obfuscation and which McIntyre has referred to as the pea under the thimble.
Mike Jackson
As johanna says, you cannot bury your past errors under the excuse of "but we do it much better now" just because there is a way of interpreting/manipulating/torturing the data that suits your case.
Oct 3, 2013 at 9:53 AM | Registered CommenterMike Jackson
It seems to have worked pretty well so far, Mike, so I don't see it stopping any time soon.
In defence, it seems quite reasonable, in some respects, to say "We are constantly working to improve are results. Why should we show anything less than our best."
So it is incumbent on the audience to remember that at every new report, the predictions [sorry, projections] will be new predictions. The new data since the last report is what you should be comparing with the old predictions. What you will first be shown, likely enough before your eyes glaze over, is the new data that has now been hind-cast with the new predictions, and thus apparently fits the model beautifully. Et voilà! Isn't modelling marvellous!
It's not like policy-makers are going to read the science anyway, but by and large, they don't need to. Just keep your eye on the projections-pea.
Then, of course, there will be the amazing expanding confidence limits.
And the important data someone really wants you to ignore, will be in a very drab colour and a whiter shade of pale.
michael hart
Oh, all right then!
"You shouldn't be allowed to bury ...." etc.
Of course you're right.They will keep on shifting the goalposts resetting the points (unmix the metaphor!) to keep the gravy train on the tracks.
And they are right to make continuing improvement a policy aim, as any good organisation should. But as you point out, that's not what they are doing. Each time the model output and the data diverge there will be a re-shuffling which will always come down to "this time we've got it right, minister. Honest."
Only they haven't. It's just another statistical artefact dressed up to look good.
Mike Jackson
Ah, "continuous improvement." It was a nostrum of managementspeak in the 1990s. Like most nostrums, it restated the obvious while providing cover for retreating from failures.
The bit they miss in this soothing miasma is that going from failure into uncharted territory is not "continuous improvement." On the contrary, c.i. means going from a soundly tested base to another, less soundly based, but promising, base.
Once again, the usual meaning of language is turned on its head.
johanna
Mike Jackson
I've just read Steve McIntyre's post and left a comment, which is currently in moderation. I also posted the same comment on today's thread, but I may as well put it here too since you ask.
I disagree with you that the IPCC is obfuscating or misleading. The published AR5 figure is better than the SOD draft version because it corrects an error and makes a more appropriate comparison between models and observations.
1. The final AR5 figure presents both model projections and observations as changes relative to a common baseline of 1961-1990, just as was done in AR4 - see here. The SOD graph, for some odd reason, used a baseline of 1990 for the models and 1961-1990 for the observations. That doesn't make any sense, which is presumably why they corrected it for the final draft.
Incidentally, Steve McIntyre himself chose to plot a model against observations in terms of changes relative to a common baseline of 1961-1990 here, so he clearly agrees with the AR4 and AR5 authors that this is the most appropriate thing to do :-)
The fact that the final AR5 figure is consistent with the equivalent AR4 figure shows that they haven't introduced anything new here - they've just done what they did before.
2. The AR4 envelope from the SOD figure, based on AR4 Figure 10.26, is from a Simple Climate Model (SCM) which only represents the long-term trend and does not include natural variability like a GCM (see here for the figure - the legend says its from an SCM). The new AR5 figure shows the spaghetti diagram from the CMIP3 GCMs, which do include natural variability.
Since natural variability is important on the timescales under consideration here, it makes more sense to compare the observations with models that include natural variability (GCMs) rather than those which don't (SCMs).
So in both aspects, the published AR5 figure is scientifically better than the SOD version, as the model-obs comparison is done like-with-like.
This is not "misleading" you - on the contrary, it's actually giving you more accurate and relevant information.