According to Dr. Clive Best, A key prediction from the 2007 IPCC WG1 report fails statistical tests.
Abstract: Global temperatures measured since 2005 are incompatible with the IPCC model predictions made in 2007 by WG1 in AR4. All subsequent temperature data from 2006 to 2011 lies between 1 and 6 standard deviations below the model predictions. The data show with > 90% confidence level that the models have over-exaggerated global warming.
Background: In 200o an IPCC special report proposed several future economic scenarios each with a different CO2 emission profile. For the 2007 assessment report these scenarios were used to model predictions for future global temperatures. The results for each of the scenarios were then used to lobby governments. It would appear that as a result of these predictions, there is one favoured scenario – namely B1 which alone is capable of limiting temperature rises to 2 degrees.
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HadCRUT4 will “fix” the problem 🙂
Sun is not helping either; watch out for more solar variability papers with
’ We propose that xyz can amplify small solar fluctuations’
The latest SIDC SSN=33 (for February) is on low side.
Dr. Hathaway had already cut back his ‘prediction’.
http://www.vukcevic.talktalk.net/NFC7a.htm
OT
Hey, we are near solar max for the SC24, and what do we have here is one sunspot and one spec. http://www.vukcevic.talktalk.net/img3.htm
Data between 2006 -2011…Um data, we don’t need data when we have perfectly good models…
I’ve been wondering for a while about the IPCC models. At what point [for each individual model] does the statistical grim reaper appear and tap the IPCC on the shoulder?
Dr. Best’s “predictions” are actually “projections” and while predictions are falsifiable, projections are not.
michael hart says:
I’ve been wondering for a while about the IPCC models. At what point [for each individual model] does the statistical grim reaper appear and tap the IPCC on the shoulder?
The grim reaper will first have to find IPCC. He should look progressively deeper in the ocean, as that is where they will be hiding.
Terry Oldberg says:
Dr. Best’s “predictions” are actually “projections” and while predictions are falsifiable, projections are not.
Then “projections” are not science, and should not be misrepresented as such. Until that fact is reflected in practice, quibbling over the distinction is just semantics.
Testable hypotheses? We ain’t got no testable hypotheses. We don’t need no testable hypotheses. I don’t have to show you any stinking testable hypotheses.
(apologies to “Treasure of the Sierra Madre”)
The math on uncertainty and number of standard deviations, and therefore the probabilities are all incorrect.
See Lucia’s Blackboard for examples of the calculations done correctly. (blog link is in the right hand column of WUWT, under “Lukewarmers”
JJ:
You seem to say that to make a distinction between predictions and projections is “just semantics.” Actually, to make this distinction is essential to one’s grasp of an important fact about the IPCC’s inquiry into AGW. Not wirhstanding IPCC representations to the contrary, the methodology of this inquiry was neither scientific nor logical.
Macro Contrarian (@JackHBarnes) says:
March 1, 2012 at 12:20 am
“So does statistical significance work in both directions?”
Yes, as the confidence intervals are + or -. However, we must remember that significance testing is typically used for sample size error confidence, only. It does not limit or measure other types of errors such as data quality, observational error (heat islands), input errors, intentional selection of data points to push a theory, non-use of other independent variables more suited to the analysis, interdependence of independent variables (multicolinearity), etc. ad nauseum.
Take a hint from Anomaly UK => http://wattsupwiththat.com/2012/02/29/day-of-reckoning-draws-nearer-for-ipcc/#comment-909129
… and Charles A. => http://wattsupwiththat.com/2012/02/29/day-of-reckoning-draws-nearer-for-ipcc/#comment-909481
I’m sorry but this analysis is nonsense. Clive is taking a temperature data-point accuracy error and applying it to a temperature time series. Makes no sense, whatsoever.
Terry Oldberg: Dr. Best’s “predictions” are actually “projections” and while predictions are falsifiable, projections are not.
Why exactly is that? The projections are cited in Congressional testimony and written exhortations as though that is what will happen if we do not act. The conditions for which the projections were made are satisfied (except that CO2 continues to rise, and a few projections assumed non-rising CO2), and the projected temperatures have not occurred. Why does that not show that the projections have been incorrect?
If Dr. Best’s “predictions” are actually “projections”, when will the AGW promoters tell us that they are of no consequence and may be ignored?
Septic Matthew:
A “prediction” is an inference from the state of a system at the beginning of an independent statistical event to the state of the same system at the end of the same event. The former state is a condition on the Cartesian product of the values of the independent variables of the model. The latter state is a condition on the Cartesian product of the values of the dependent variables of this model. Conventionally, the latter state is called the “outcome” of the associated event. The complete set of events is an example of a “statistical population.” When the elements of a subset of these events are observed, this subset is a “statistical sample.” In testing a model, one compares the predicted to the observed relative frequences of the various possible outcomes. If there is not a match, the model is falsified by the evidence.
The relationship between the events and the predictions is one-to-one. Thus, a necessary condition for predictions to be made by a model is for a statistical population to be referenced by it. If you were to search AR4 for a citation to the statistical population underlying the IPCC’s conclusions, you’d draw a blank, for there is no population. It follows that: a) the IPCC models cannot be statistically tested and b) the methodology of the IPCC’s inquiry into AGW was not scientific.
In the minds of many, “projections” play the role of “predictions.” However, this cannot be so in view of the missing statistical population. The conflation, by professional climatologists and others, of the idea that is referenced by the word “projection” with the idea that is referenced by the word “prediction” has produced the ultimate disaster for the IPCC’s inquiry into AGW. This is for the inquiry to have been regarded as a scientific inquiry when it was not one.
The poster has the slope for CO2 wrong. Since 1997, it is about 2 ppm/year and not 1.
(slope = 1.95337 per year)
http://www.woodfortrees.org/plot/esrl-co2/from:1980/plot/esrl-co2/from:1997/trend
@Werner Brozek
Sorry for Typo – yes it should be 2ppm per year. It has been fixed now.
The January 2012 value for HadCrut3 at about 0.22 certainly does not help THE CAUSE. At 0.22, it would rank 18th hottest. And UAH for February certainly will not help either.
http://www.climate4you.com/GlobalTemperatures.htm#HadCRUT3%20TempDiagram
The strategy now used at RealClimate and Barry Brickmore is to state that the predictions are still within the experimental (data) errors as discusssed in Barry Brickmore’s blog on the WSJ article. The authors of this latter article argued that the overprediction of the temperature anomalies disproves the climate models. The spread in the different model predictions is so large that we may have to wait until 2030 to really test the predictive capability of the climate models. As argued by Judith Curry in her blog while discussing fig 9.7 of the FAR IPCC report, the model and experimental errors may be too large to effectively test the climate models.
Steptoe Fan on February 29, 2012 at 10:59 pm:
this is terrific ! I want to try and get this poster into local middle and high schools.
Werner Brozek on March 1, 2012 at 11:31 am:
The poster has the slope for CO2 wrong.
Are you all talking about this here poster linked to on the originating piece? If so, it might have been nice to clarify that point.
For myself, the attempted download of the poster on dial-up has now conked out early four times straight. Seems like a hosting issue, his site uses wordpress software but it doesn’t appear to be hosted on wordpress-dot-com. While I guess it’s interesting to look at, I’m giving up for now.
Heh … I’ve been betting on +0.3 deg C for a good many years … wish I’d bet real money!
Will the REAL deniers please stand up.
The really funny thing about the AGW con is that the “true believers” call opponents “deniers”.
Only a blind fool could miss the “Inconvenient Truth” that it is the true believers who are the deniers – they deny reality with their ludicrous theory which has NO substantiated evidence to support it.
They got the whole basis for their theory wrong by missing the really obvious fact that during the day the atmosphere acts to reduce the heating effect of the solar radiation – not add heat as they idiotically claim.
Is there any proof ??
You betcha – because without an atmosphere to REDUCE the heating effect of the solar radiation during the day – and after all during the day is all that matters as there is NO solar radiation at night – I thought that needed explaining to people who deny reality – the Earth would be subjected to temperatures like the Moon – about 120 degrees C.
After all, both the Earth and Moon are subject to the same intensity of solar radiation !!
So – CLEARLY – the Earth’s atmosphere actually REDUCES the heating impact.
Only a real DENIER could argue that isn’t true.
So the real “deniers” are actually the “true believers” – those who deny reality in favour of their pet “religion”.
Ha-ha! Great comment at the original story:
Jackie then included a link to RealTrueClimateStories, where presumably the Climate Science™-approved method to always uphold the IPCC is revealed. Guess that means if ain’t Team-reviewed then it ain’t science, and if it ain’t science then it is exactly the type of Gleick-ness suitable for posting at WUWT.
Ah Jackie, it’s good to know you have such a high opinion of this site. So, do you have any suggestions for improving the content on this site, that you’ll gladly and openly reveal here in Anthony’s home on the internet, right in front of Anthony’s virtual face?
Reply : Jack Greer et al.
The basic argument is that a prediction was made in 2007 for a future temperature trend. Now in 2012 we compare how well that prediction has performed fro 2011 until 2011. The conclusion is that it has significantly overestimated all temperatures for the last 6 years. These are not random errors – they are systematically low.
Each model should strive to fit the data independently. Taking an ensemble of different models with chosen parameters, then selecting the mean and using the spread as some sort of “model error” is also meaningless. Instead each individual model should be run multiple times varying climate sensitivity until it best reproduces the data. Fighting turf wars makes no sense. There is nothing wrong with being wrong. If it finally turns out that climate sensitivity is smaller than feared then we should celebrate. There is no need for gnashing of teeth ! The next ice age is anyway only 2000-3000 years away !
Terry Oldberg says:
March 1, 2012 at 12:57 pm
You and I are on the same page. The use of the “prediction/projection” distinction is a semantic argument by warmists to avoid responsibility for the scary stories they tell. In their lexicon, a “projection” is simply a “prediction” they made that turned out to be demonstrably false.
It is worth noting the official IPCC definitions, which suborns this nonsense:
Projection: “…a projection can be regarded as any description of the future and the pathway leading to it. However, a more specific interpretation has been attached to the term “climate projection” by the IPCC when referring to model-derived estimates of future climate.”
Forecast/Prediction: “When a projection is branded “most likely” it becomes a forecast or prediction. A forecast is often obtained using deterministic models, possibly a set of these, outputs of which can enable some level of confidence to be attached to projections.”
There is no formal distinction between an IPCC “climate projection” and a “forecast or prediction”, there is only their arbitrarily generated and ambiguosly quantified “confidence” that a projection is “most likely”.
They are responsible for this mess … and for their predictions, whether they want to call them that or not.
JJ:
I’m not sure we’re on the same page. I’m saying that, as predictions are one-to-one with the events in a statistical population and as there is no population, there are no predictions. Thus, the use of the word “prediction” by Dr. Best, the IPCC and many others is false and misleading. While in the absence of a statistical population, a model cannot make predictions, it can make projections. Climatologists have muddied the waters by failing to draw a distinction between a “prediction” and a “projection” leading the naive to the false conclusion that the IPCC’s models can be statistically tested when they cannot be statistically tested. Do we agree?
On another blog, make a claim about global warming. I responded with actual data and a few links.
His response was something along the lines of:
Baseball has it’s umpires.
Football has it’s referees.
For science, we have the National Academy of Sciences.
Since the Academy has spoken, the issue is now settled.
He wouldn’t even debate the facts I presented. The NAS has spoken and that was it.
@Clive Best says: March 1, 2012 at 2:22 pm
Clive, Please explain your logic for using a temperature data-point accuracy error value to estimate the statistical significance of how far adrift model projections are v. real measurement for a temperature time series. Seriously, I’m curious.
@Jack Greer.
My logic is the following: Quantum Chromodynamics predicts the cross-section for gluon production in quark-quark scattering. The calculation is difficult but eventually makes precise predictions about 3-jet events in a particle accelerator. Physicists work for several years to build an experiment to measure the cross-section for 3 jet production. QCD is compared to the results. and they agree within measurement errors.
Global Warming: At one instant in time – 2007: Some climate models which have been tuned to describe past temperature changes up to 2005 (or time series if you prefer) are then used to calculate forward in time to project/predict future temperature rises. These models include CO2 forcing trends and various assumptions for feedbacks, aerosols, albedo change etc.
Now in 2012 we can take the 6 new measurements since then and see how well the models performed. The answer in this case is not very well. All the points range from 1 to 6 standard deviations below the prediction.
What I think you want me to say is something like : Over a 50 year period the chi-squared agreement between climate models and the data is reasonably good so the models are doing just fine. However, this is based on “hindcasting” which I think is not quite the same thing. If I know the answer then It is easier to get the model to agree with the data. It is a bit like those mechanical models used to predict planetary orbits before Newton. By adding more cogs they get closer to an accurate description only if the underlying physics is very simple – Gravity.