Reader Jimbo advises in WUWT Tips and Notes about something Dr. [Kevin Trenberth] wrote that makes you wonder what he’s talking about when there are so many uses of the word “prediction” in the IPCC AR4. It also makes me wonder what the Economist author Oliver Morton was doing running a blog by Nature. Is there no separation between science journalists and science journals?
Trenberth suggests that after the last report “…the science is settled or done and now is the time for action.”. Here we are six years later, and another IPCC report is coming out on that “settled science” and there is no successor to Kyoto. I wonder how many times the word “prediction” will be used in the upcoming AR5?
Jimbo writes: I stumbled on a quote from [Kevin Trenberth] over at the Nature Blog dated 04 Jun 2007.
Source: http://blogs.nature.com/climatefeedback/2007/06/predictions_of_climate.html
I thought I’d take a look because I was sure I had seen the IPCC use the word ‘predict’.
[My bolding throughout]
This subsection focuses on the few results of initial value predictions made using models that are identical, or very close to, the models used in other chapters of this report for understanding and predicting climate change.
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch8s8-4-11.html
—————–
…Some qualitative inconsistencies remain, including the fact that models predict a faster rate of warming in the mid- to upper troposphere which is not observed in either satellite or radiosonde tropospheric temperature records….
…The first IPCC Scientific Assessment in 1990 (IPCC, 1990) concluded that the global mean surface temperature had increased by 0.3 to 0.6°C over the previous 100 years and that the magnitude of this warming was broadly consistent with the predictions of climate models forced by increasing concentra- tions of greenhouse gases. However, it remained to be established that the observed warming (or part of it) could be attributed to the enhanced greenhouse effect. Some of the reasons for this were that there was only limited agreement between model predictions and observations,…
…However, models generally predict an enhanced rate of warming in the mid- to upper troposphere over that at the surface (i.e., a negative lapse-rate feedback on the surface temperature change) whereas observations show mid-tropospheric temperatures warming no faster than surface temperatures….
…..“historical” indicates the signal is taken from a historical hindcast simulation, “future” indicates that the pattern is taken from a prediction……
…Changes in the annual mean surface temperature were found to be highly significant (in agreement with previous results from Hegerl et al., 1996, 1997). The predicted change in the annual cycle of temperature as well as winter means of diurnal temperature range can also be detected in most recent observations….
…Estimation of uncertainty in predictions
The scaling factors derived from optimal detection can also be used to constrain predictions of future climate change resulting from anthropogenic emissions (Allen et al., 2000b). The best guess scaling and uncertainty limits for each component can be applied to the model predictions,……
… An example based on the IS92a (IPCC, 1992) GS scenario (whose exact forcing varies between models, see Chapter 9, Table 9.1 for details) is shown in Figure 12.13 based on a limited number of model simulations. Note that in each case, the original warming predicted by the model lies in the range consistent with the observations….
…The range is significantly less than one (consistent with results from other models), meaning that models forced with greenhouse gases alone significantly overpredict the observed warming signal….
…All but one (CGCM1) of these ranges is consistent with unity. Hence there is little evidence that models are systematically over- or under- predicting the amplitude of the observed response/ under the assumption that model-simulated GS signals and internal variability are an adequate representation (i.e. that natural forcing has had little net impact on this diagnostic)….
…Original model prediction under IS92a greenhouse+sulphate forcing…
…The SAR predicted an increase in the anthropogenic contri-bution to global mean temperature of slightly over 0.1°C in the five years following the SAR, which is consistent with the observed change since the SAR (Chapter 2). The predicted increase in the anthropogenic signal (and the observed change) are small compared to natural variability, so it is not possible to distinguish an anthropogenic signal from natural variability on five year time-scales….
http://www.ipcc.ch/ipccreports/tar/wg1/pdf/TAR-12.PDF
——————-
…During the early summer season, October to December, both models predict drying over the tropical western side of the continent, responding to the increase in high-pressure systems entering from the west, with MM5 indicating that the drying extends further south and PRECIS further east….
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch11s11-2-3-2.html
——————-
…The IPCC commissioned a Special Report on Emissions Scenarios (SRES). Four “marker scenarios” representing different world storylines are used to estimate emissions and climate change to 2100 (IPCC, 2000). Table 16-1 summarizes these climate projections for the polar regions. In almost all cases, predicted climates are well beyond the range of variability of current climate. …
http://www.ipcc.ch/ipccreports/tar/wg2/index.php?idp=599
——————-
…The chemical and physical properties of aerosols are needed to estimate and predict direct and indirect climate forcing….
…Modelled dust concentrations are systematically too high in the Southern Hemisphere, indicating that source strengths developed for the Sahara do not accurately predict dust uplift in other arid areas….
…For summertime tropopause conditions the range of model predictions is a factor of five for sulphate. The range of predicted concentrations is even larger for some of the other aerosol species. However, there are insufficient data to evaluate this aspect of the models….
Jimbo:
I write to provide an addition to the excellent point you provide in your post at August 27, 2013 at 1:10 pm
http://wattsupwiththat.com/2013/08/25/trenberths-ipcc-claim-of-no-predictions-by-ipcc-at-all-refuted-by-ipccs-own-words/#comment-1401336
As you say, the IPCC defines in its terminology
However, Trenberth (supported by DAV and Nick Stokes in this thread) has disputed that a projection can be a prediction. Trenberth claims the IPCC only makes projections but not predictions.
As I have shown in this thread, even if one were to agree with Trenberth’s version of what constitutes a prediction then Trenberth is wrong. The IPCC has made at least one prediction on the basis of an “energy balance” and NOT on the basis of a projection.
Trenberth is wrong – as you have shown – according to the IPCC
and
Trenberth is wrong – as I have shown – according to his own version of what constitutes a prediction.
Richard
Reed Coray says: August 27, 2013 at 11:55 am
‘Nick Stokes says: August 26, 2013 at 2:38 pm
Clear but wrong. Just look at how your first “we predict” statement starts:
“Based on current model results, we predict:
Nick, aren’t all “predictions” based on something.’
No, you’ve cut the next sentence, just as in this thread Trenberth’s statement was cut to distort what he was actually saying. His point was that the IPCC projected, or predicted, subject to scenario. In later years, they consistently used the word projected to emphasise this. Back in 1990, they didn’t have that convention, but as I quoted, in that 1990 statement they immediately stated the scenario, as Trenberth said.
Jimbo says:
August 27, 2013 at 1:10 pm
I guess in this one instance, IPCC statements are rational then, since they recognize their “most likely projections” as the predictions they obviously are & must be, to resemble science.
In which case, massive fail.
Nick Stokes,
Trenberth is wrong. He was wrong then and he is wrong now. Why would anyone think he is credible? He’s just another tax-sucker riding the grant gravy train at everyone else’s expense. You are being his enabler. Shame on you for supporting the “carbon” scam.
“”””””…….milodonharlani says:
August 27, 2013 at 12:06 pm
If the IPCC doesn’t make predictions, then it’s not scientific, but unscientific, indeed anti-scientific.
If however its “most likely” projections are, as any rational person would conclude, in fact predictions, then the forecasts have been falsified & the assumptions & models upon which they were made have been shown worse than worthless GIGO…….””””””
A rational person would presume that the “””…”most likely”…””” projections are a consequence of applying the “most credible” theory to the “most robust” experimentally available data.
Anything other than the “most likely” projections ought to then be discarded, as being inconsistent with the best available evidence.
And if those “most likely” projections are NOT in fact PREDICTIONS of the eventual outcome; then they too must be discarded as simply garbage ; and certainly not Science.
Stop trying to weasel meaning into words, that is contrary to their well accepted meaning. (all of us)
Nick Stokes is now an official LIAR.
Nick Stokes is an official DENIER.
Nick Stokes should no longer be taken seriously. [Look at his first comment & lie]
Nick Stokes is back again trying to defend his JOB.
Nick Stokes is trying to defend failure.
Should I take Nick Stoke seriously?
richardscourtney you are in touch with reality. Nick Stokes has lost but won’t admit it. He made a challenge which was met. Being a climate modeler is not easy. Good luck Nick Stokes, the temperature standstill can be a bummer.
Nick Stokes,
A ‘projection’ can be a ‘prediction’ according to the IPCC. Yet, you argue that the IPCC does not make ‘predictions’. Have you informed the IPCC of their error?
Jimbo,
You haven’t met the basic challenge of this post – quote the IPCC actually making a prediction about future climate that is not of the kind that Trenberth said they do make – subject to a scenario.
And no, I’m not a climate modeller, though I think they are smart guys.
Your post is a collection of juvenile gotchas. What Trenberth said, when you don’t just pluck out a few words, was clear, correct and not controversial.
At the risk of boring you all the following is why I initially commented to WUWT tips and notes.
Sorry.
The last paragraph is my comment.
Nick Stokes you said:
Game, set and match. You have lost and failed. Give it up my friend.
Nick Stokes is a persistent character. Even when he is wrong, he is right. LOL.
How is the climate modeling going Nick Stokes? How are global mean surface temps hanging over the last 16 years?
Nick Stokes cannot read. Nick, look upstream, I addressed it. I even mentioned ‘scenario’ and ‘scenarios’. It was still a prediction! The IPCC have been so kind to provide a page where they actually define what they say are predictions. Have you looked at the page?
Nick, you really do need to get in touch with the IPCC or a head doctor.
Nick Stokes, do you agree that the sign of any good THEORY is the ability to make a PREDICTION? Einstein did it. He was so smart that he did not need to project or forecast a damned thing, he predicted and is waiting to be falsified on relativity. Why can’t climate scientists?
Jimbo says: August 27, 2013 at 7:20 pm
“Nick Stokes, do you agree that the sign of any good THEORY is the ability to make a PREDICTION? Einstein did it.”
Almost all theories predict subject to a scenario. You can make some absolute predictions about astronomical matters, because there is no possibility of human intervention. But not otherwise. Can you think of any events on a human scale that Einstein predicted? Time and place?
Sending a rocket to go around the moon is something that scientists have good theories about. But you can’t just say – hey scientist, predict the path of this rocket. He’ll say, well, it all depends on what you do with the controls. That’s the scenario. Without it, no prediction. But he can tell you what would happen under a number of scenarios. That’s basically how rocket journeys are planned.
Nick Stokes,
I hope sincerely that you get my main point and it’s a simple one. Trenberth said in 2007 the the IPCC has never made a prediction.
Subsequently it has been made clear by the IPCC’s own definitions page that they in fact do make predictions. Whether it’s based on ‘what if’, a scenario or forecast does not matter. The language is in conflict with Trenberth’s assertion that “there are no predictions by IPCC at all. And there never have been.”
As you can clearly see the IPCC says when they label a “projection” as “most likely,” it becomes a “prediction”. How a prediction is arrived at or formulated is not important. The FACT is that the IPCC has made predictions in the past. It also creates scenarios, forecasts and projections.
Below they have not even bothered with “what if” but flat out make a prediction based on model results under a scenario.
Having read all this as well as other examples above I can’t see how you could possible stand by Trenberth’s assertion in bold, when the IPCC goes so far as to define what constitutes a prediction!
As you can see it does not matter how a prediction is formulated. The IPCC clearly tells us that it makes predictions which contradicts Trenberths’s false assertion that:
“In fact there are no predictions by IPCC at all. And there never have been. “
Compare and contrast these two statements.
In concluding that the IPCC climate models predict, the IPCC and richardscourtney draw a conclusion from an equivocation thus being guilty of the equivocation fallacy.. An “equivocation” is an argument in which a term changes meaning in the midst of this argument. By logical rule, a proper conclusion may not be drawn from an equivocation. To draw a conclusion, as the IPCC and richardscourtney do, is the “equivocation fallacy.” Here, the term that changes meaning is the word-pair prediction/projection wherein the two words are treated as synonyms even though each of the two words has a different meaning.
A model that predicts conveys information to a policy maker about the outcomes from his or her policy decisions. A model that projects conveys no such information to a policy maker. It can be demonstrated that each of the climate models referenced by AR4 projects and that none of them predict. Thus, none of these models support policy making on CO2 emissions. The equivocations of the IPCC and richardscourtney, among many others, obscure the uselessness of the fruits of past global warming research in making policy. Details of my argument are available in the peer-reviewed article at http://wmbriggs.com/blog/?p=7923 .
Terry Oldberg:
Your post at August 28, 2013 at 9:58 pm
http://wattsupwiththat.com/2013/08/25/trenberths-ipcc-claim-of-no-predictions-by-ipcc-at-all-refuted-by-ipccs-own-words/#comment-1402561
is fallacious nonsense.
You very recently made the same daft and ignorant assertions on another thread, and I refuted it at
http://wattsupwiththat.com/2013/08/27/the-hottest-temperature-game/#comment-1402152
To save others needing to find it, I copy my refutation below.
Richard
———————-
richardscourtney says:
August 28, 2013 at 1:36 pm
Terry Oldberg:
At August 28, 2013 at 12:29 pm
http://wattsupwiththat.com/2013/08/27/the-hottest-temperature-game/#comment-1402076
you are being egregious when you accuse Tim Ball of making an equivocation error in his article but you do not state what it is.
The accusation is especially offensive because your post demonstrates you do not understand what you have written.
You say
No.
I list some of the misunderstandings concerning equivocation and of IPCC predictions stated in your words I have quoted here.
1.
You are incorrect when you say
That is not true. The truth is
An equivocation is an argument in which one or more terms change meaning in the midst of the argument. By logical rule, a proper conclusion may not be drawn from an equivocation THAT AFFECTS THE CONCLUSION.
2.
You mislead when you claim
In its definitions the IPCC says
Forecast/Prediction. When a projection is branded “most likely,” it becomes a forecast or prediction. A forecast is often obtained by using deterministic models—possibly a set of such models—outputs of which can enable some level of confidence to be attached to projections…..
So, the IPCC defines a prediction is the projection with highest confidence.
The definition does NOT provide an equivocation because the definition makes a clear distinction between
a prediction (i.e. the forecast with highest confidence)
and
a projection (i.e. a forecast with less confidence than another forecast).
Furthermore, a projection can be converted to become a prediction if it gains confidence, and this does not create an equivocation.
It is important to note that a projection can become a prediction without there being an equivocation. And whether or not your paper has been peer–reviewed has no relevance to this.
3.
You are plain wrong when you say
The IPCC defines that a model’s projection with highest confidence is a prediction.
When the IPCC provides a forecast that the IPCC says is a prediction then the IPCC has made a prediction.
How and why the IPCC made that prediction does not – and cannot – prevent that prediction from being a prediction.
4.
You make a logical error when you refuse to accept a forecast as being a prediction when the forecaster states the forecast is a prediction.
The forecaster alone knows the intention of the forecast. And it is not possible for anyone else to know the intention of the forecaster is other than the forecaster says.
Therefore, when the forecaster says the forecast is a prediction then there is no possibility of anyone disproving it is a prediction: the most anybody can do is to show the prediction is improbable.
In light of the above, I am willing to accept that your unsubstantiated affront to Tim Ball derives from you not knowing what you are talking about. But, whatever your reason for that affront, you need to withdraw your assertion or substantiate it.
Richard
Friends:
I think it important to add information for others following my post to Terry Oldberg at August 29, 2013 at 3:33 am
http://wattsupwiththat.com/2013/08/25/trenberths-ipcc-claim-of-no-predictions-by-ipcc-at-all-refuted-by-ipccs-own-words/#comment-1402713
Firstly, I answered Oldberg because his objection was to me and the IPCC. However, as anybody can see, Oldberg was disputing the point made by Jimbo in this thread but I have been making a different argument. I have been pointing out that the IPCC has made at least one prediction which is based on existing “energy ballance” and not on the basis of any scenarios or projections. Until Oldberg raised his complaint at me I had not addressed Jimbo’s point because Jimbo needed no support.
Secondly, and very importantly, I have been refuting Oldberg’s fallacious twaddle for some time because – as I have repeatedly said – that twaddle provides an excuse to the IPCC for its errors. (That is why Oldberg addressed his post to me and not Jimbo).
As the subject of this thread shows, Trenberth has adopted and has now proclaimed – the same fallacious excuse for the IPCC errors that Terry Oldberg has been promoting.
Richard
The IPCC has defined what makes up a prediction. The IPCC has made at least one prediction. If anyone has a problem with that go raise it with the IPCC. Trenberth lied.