Prediction is hard, especially of the future.

As Maxwell Smart used to say, holding his index finger and thumb a tiny distance apart, “Missed it by that much.”

I begin to believe that everybody is supposed to take on faith, what these “prognosticators of doom” people say — They just assume no one will actually do the math. Bad assumption.
For sure the world media and to some extent, supposed real science publications, have shown their willingness to just accept what they say, as is … Such is the price of the AGW money scam.

Careful Mr Eschenbach, i can see portions of that last paragraph being selectively quoted/paraphrased to actually SUPPORT the models’ effectivenes… think back-of the box DVD covers where one word (stupendous!) is taken as a review (where the whole review is a stupendous waste of time…. etc etc.
This is interesting and something i REALLY want to see more of; the models are their main reason for forcing these idiotic measures down our throats (at great expense)- i have never been convinced to their accuracy- lets see more, open and detailed investigation of this sort of thing.
Would REALLY love to hear back from them.
Sugegstion- perhaps instead of asking after the fact, a ‘joint’ article could be prepared? They may be more likely to respond if it’s done that way.

I think what was meant by “accurate” was that it cooled rather than warmed … and after all when you are dealing with a doomsday religion regarding CO2 isn’t it a perfectly adequate proof to show that particulates cause it to cool!
I shall now go and make a cup of cocoa because I fancy a coffee … or at least that seems to be the way logic works these days!

Willis,
Predictions are mathematical formulas on temperatures.
Actual physical evidence is classed as theory with no one looking into this phenomena as you cannot put a mathematical model to it.

Nostradamus to his wife: “Prediction is hard, especially of the future…….if you don’t look at the stars”

Willis,
I do a great deal of following the physical evidence trail that our planet has implanted as clues.
This is a very difficult trail as the actions of this planet are ALL interactive.
You have to have a HUGE knowledge base and disregard what current physics says as LAWS as these generate road blocks to understanding the planets evolution and transformation.
Physics today will not stand to billions of years ago when our planet was rotating faster and the oceans were saltier.
So, unless current science learns and changes, garbage science will be continue to be passed down to generation as it already has.

Yes, I think it very strange Hansen’s Pinatubo model is brought up. I thought this was dispatched to the trash heap years ago. It could be that is was a different Hansen contrivance that I’m thinking of, they all bear a commonality of failure so I easily get them confused. But they haven’t improved upon this work? What the heck have they been doing for the last 20 years? Did they get confused about what models they were working on and buy a bunch of glue and plastic parts?
As usual Willis, nice job.

Mobs + tar + feathers = what the AGW scare mongers deserve.
Or, loss of funding. Either one would probably improve the accuracy of the climate models.

Speaking of Hansen, Figure 6 in his 1981 paper (http://www.edge.org/q2005/q05_8.html) made a projection of temperature. It might be a good idea to plot actuals on that same graph as the basis for a continuing evaluation of his predictive capabilities.

While it is nice to get the sign of the effect right, as Hansen does, the entire global warming debate is about magnitudes. The volcano effect is particularly important because it is supposedly human-emitted sulfate aerosols (also the cause of the volcano effect) that are masking the “true” anthropogenic effects. If they predict twice as strong a sulfate aerosol effect as occurs with Pinatubo, then the masking they assume (even if the forcing data were valid, which I doubt) is twice too strong and the greenhouse warming effect they are modeling is too strong (to overcome their assumed aerosol forcing).

I have spent a large part of my 30 years in the oil industry building numerical models of oil fields and “history matching” them – that is, adjusting input data (much of which is either totally unknown or known only with high degree of uncertainty) so that the model “matches” the “history” (of course the model runs are really predictions of the past, and recently I have seen the term “hindcast” being used). This is a tedious process and the results are very non-unique, since there are so many unknowns (more unknowns than equations, to use the linear algebra analogy).
Anyway, I bring this up to say that the Mt. Pinatubo eruption is a perfect opportunity to “tune” a model – to adjust the model’s sensitivity to a specific input (“forcing”). It is obvious that the GISS model was too sensitive to the effect of aerosols, and the aerosol “knob” needs to be turned down a bit. Now doing that would of course ruin the rest of their hindcast, so other knobs would have to be adjusted to compensate, but that is the nature of history matching. The eruption data would basically allow the modelers to set the aerosol knob and then take it out of the set of unknown parameters being adjusted to match the history.
So, rather than a opportunity for patting themselves on the back for “getting the direction right,” they should have taken the opportunity to improve their model.

What could possibly account for this error where the forcing is correct but the model output is wrong? Oh ya, if the models have the climate sensitivity wrong.

Trying to model the impacts of volcanic eruptions on temperature is futile because there’s no way of segregating volcanic impacts from the “noise” created by El Niños and La Niñas and other short-term influences. There are at least ten short-term cooling episodes in the 20th century temperature record that look just like Pinatubo but which are unrelated to volcanic eruptions. And not all volcanic eruptions caused temperatures to decrease. One of the largest (El Chichón 1982) was in fact followed by a temperature increase.
Volcanic eruptions receive so much attention because the temperature record shows cooling after 1940, and climate models can’t hindcast this cooling without a significant volcanic contribution (although they still do a pretty poor job of it). In other words, the models simulate just one short-term forcing – the one that fits the theory – and ignore all the rest.

The truly amazing thing to me is that there are so few attempts to test the models. Because of the Pinatubo paper it can be assumed agreed that the way to test a model is to input real data from the past, run the model, finally compare the run with what was actually observed. Vast amounts of time and money have been spent, massive distortions imposed on the economies (of some countries) because of the CAGW theory. But the tests of the theory that are available have not been performed. Sure, it might take a lot of work to perfect these tests and they will no doubt be subject to criticism like all of science. But that they have not been tried …. it staggers the imagination.
The great philosopher Karl Popper demarcated science by the capacity to admit falsification. That massive insight seems to have been lost, and perhaps more recent philosophy of science is culpable there. Possibly now that CAGW is in retreat the requisite testing will start to be done?

That is most interesting. When astrophysicists are asked about the relationship between solar activity and weather, they often point to 1816, the year without a summer. A year of extraordinary solar quiescence. Warmists counter that solar activity had little to do with it, that it was the eruption of Tambora the year before. Given the shallow atmospheric response as well as the very quick recovery evidenced by the Pinatubo temperatures above, I suspect both are right.
http://en.wikipedia.org/wiki/Year_Without_a_Summer

@Houston, we have a problem…
I completely agree. This is/was a good opportunity to improve their parametrization. However, the bind that Lacis et al are in is that they have claimed certainty, and now cannot improve their models, or data analysis methods, for fear of admitting that they were wrong.
Their only recourse at this point has been to ramp up the cut-and-paste publications, and hope that policy changes are enacted, such that they can claim that disaster was averted. (cf. the CFC fiasco). The situation may well still play out in this direction – the UN, politicians, and bankers are powerful allies. But whatever is going on in climatology – science left long ago.

Interesting post Willis,
Atmospheric mixing, the goofy notion of Global temperature, and assumptions about the SO2 extent are factors that come to mind related to the inaccuracy of the model.
The eruption occurred on June 15 from 1:45 – 10:45 pm from the Manila area dumping ash and aerosols in a South Eastern direction towards Singapore in the South to Bangkok in the North. At the time of the eruption Tropical Storm Yunya was passing 75 km (47 miles) to the northeast of Mount Pinatubo, causing a large amount of rainfall in the region.
It said to have injected millions of tons of SO2 into the Troposphere which created a “global” Sulfuric Acid haze in the upper atmosphere but the question seems to be extent?
Are the estimates wrong because most of the SO2 ended up as acid rain in the Indian Ocean and because most of the “global” temperature readings are from the Northern Hemisphere?
Global impacts take time and, as I understand it, the atmospheric mixing moves from the Northern Hemisphere to the Southern. The greatest temperature impact would have been in the Southern Hemisphere?

“If you want to asess a model realistically, you need to understand such factors as the uncertainty in the observations, the underlying assumptions, and any simplifications that have been made, among other things.”
You should tell Hansen, et al exactly the same thing, as these are the very reasons that models and computer simulations on climate don’t work. There is just too much uncertainty and lack of understanding of the interelated processes that drive climate, not to mention the bad faith adjustments and temperature smoothing practiced by the global warming/climate chaos/climate change gang of junk scientists.
Really, I’ve lost faith in science in the public interest as it has been mostly taken over by a gang of leftist/liberal activists intent on controlling and redistributing the wealth of the Western World, mostly in an attempt to destroy the very institutions that built the wealth they enjoy the fruits of. These people hate the West, hate themselves(if only they were born a minority), and wish to destroy all vestiges of Western Civilization. One only has to look at the groups supporting the green iniciatives and global warming nonsense to see the truth, although there are a few well-meaning but useful idiots who support them as well.

Another interesting factor to consider, if you roll the “way-back machine” to 1991, we appear to have been moving into an El Nino which would have compensated for a significant portion of the cooling.

Cracking good first question to Lacis (he said, not allowing false modesty to overwhelm him)
And its worth noting that rather than the 5 or 10 ‘proof points’ that he was offered the chance to discuss from the whole palette of climate modelling, he came up with just the one that Willis discusses and one other, also by himself. And made no better a job of it either.
It is quite remarkable how little the individual Climatologists know of each others work, while feeling able to dismiss any ‘outsiders’ criticisms as ignorant or unqualified.

Great article and great comments too. Thank You all. Not to belabor the point or recover old ground for the tenth time, let me just add: expectations and realizations are almost always mismatched, mostly because we humans generally fail to recognize our ignorance.

I have a memory of the boot being applied to this paper previously, noting the advent of an La Niña coinciding with the cooling period attributed to Pinatubo.
So, were NASA predictions based upon a “Constant Temperature” pertubation or a “Reduction in temperature” pertubation by the eruption?

Thanks Willis, great post. For all who label this as nitpicking, does it not seem strange to you yet that every single error shown in every analysis of climate models always goes towards exaggerating the magnitude of the effect of CO2?

The modelers face a dilemma. On one hand, they need to make their models match reality, basically by getting the hindcasting right, which would also have the side-effect of getting events like Pinatubo half way right for a short time into the future.
On the other hand, they need to deliver catastrophic outcomes in the long range, and they can’t do this in a too open manner in the source code, for instance by just increasing the amount of energy in the system over time; it would be too obvious.
When i say they NEED to deliver catastrophic outcomes, i don’t mean that all modelers are dishonest crooks; but there is a natural selection amongst researchers through the grant mechanism that favors those that deliver the catastrophic predictions. This mechanism constantly purges the moderates and prefers the extremists.
So to SURVIVE, a modeler needs to deliver catastrophic predictions while at the same time hindcasting the past correctly. It is NOT important whether a given model proves to be correct after 10 years because grants are not issued according to such evaluations. So it is not important for the survival of the modeler whether what he predicts now comes to pass in 10 years; he can refine his model many times and revise his opinion without punishment.
Nothing in the selection process rewards correct models.

“Because this result does nothing … to establish the fidelity and trustworthiness of models”
It certainly does do something. Only a fool would dismiss it entirely, as you seem to be doing. No model ever predicts the future to 27 decimal places, as you seem to be demanding it should.

Craig Loehle says:
December 29, 2010 at 7:28 am
While it is nice to get the sign of the effect right, as Hansen does, the entire global warming debate is about magnitudes. The volcano effect is particularly important because it is supposedly human-emitted sulfate aerosols (also the cause of the volcano effect) that are masking the “true” anthropogenic effects. If they predict twice as strong a sulfate aerosol effect as occurs with Pinatubo, then the masking they assume (even if the forcing data were valid, which I doubt) is twice too strong and the greenhouse warming effect they are modeling is too strong (to overcome their assumed aerosol forcing).

—————
Craig Loehle,
I think that Hansen’s prediction for the climate effects of the 1991 Pinatubo eruption is not consistent with an assumption of someone like him having a premeditated strategy to overstate the aerosol effect in a model.
I would say that if someone like Hansen wanted to have an effective premeditated strategy in a Pinatubo effect prediction then he should have purposely and significantly underestimated the aerosol effect in his model prediction. That way one could look at the actual climate effect of Pinatubo being more than his model predictions; and then AGW supporters could say something like ‘Hey, we need to increase the AGW forcing in models because we underestimated the aerosol forcing as compared the actuals shown by the Pinatubo example.’
So, to me this means someone like Hansen really thought the aerosol forcing in their models really was going to be that large in reality and so had no premeditated strategy for the model outcome.
John

@ Stevo
Dude, if the GISS model missed the hindcast of a simple event like Mt Pinatubo by 100%, does that not give you any qualms about accepting the PREDICTIONS (ie, extrapolation) from that model about a very complex event, like what is the global temperature in 2100?

The Globe cooled 0.56 Degree Celsius in only four days
Pretty much all of 20th century global warming may have been eradicated within 4 days – the same time that Apollo 11 needed to get to the Moon, as correctly predicted by Jules Verne.
http://motls.blogspot.com/2010/12/globe-cooled-by-056-c-in-four-days.html

AGW Progress Report.
…-
“Y2Kyoto: Would You Prefer Your Temperatures Fried Or Boiled?
Daily Bayonet;
New Zealand’s Climate Science Coalition has issued a press release detailing the end of the Kiwi-gate affair.
The outcome is that data published in 2009 by New Zealand’s National Institute of Water and Atmospheric Research (NIWA) entitled ‘Are we feeling warmer yet’ has been abandoned and replaced with real, unadjusted data that shows a picture that warmists don’t want you to see:
NIWA makes the huge admission that New Zealand has experienced hardly any warming during the last half-century. For all their talk about warming, for all their rushed invention of the “Eleven-Station Series” to prove warming, this new series shows that no warming has occurred here since about 1960. Almost all the warming took place from 1940-60, when the IPCC says that the effect of CO2 concentrations was trivial. Indeed, global temperatures were falling during that period.
Well, it’s only New Zealand, right? Well, there’s lots more chewy chart goodness here!”
http://www.smalldeadanimals.com/

Stevo says:
December 29, 2010 at 9:41 am

It certainly does do something. Only a fool would dismiss it entirely, as you seem to be doing. No model ever predicts the future to 27 decimal places, as you seem to be demanding it should.

What are you on about Stevo? And calling Willis a fool? I see a smackdown coming your way.

Stevo and others,
Please no accolades for getting the sign right! Heck, I predict that the next major eruption will have the same sign and I did this with the common sense model we all are equipped with.

Stevo says:
December 29, 2010 at 9:41 am
“Because this result does nothing … to establish the fidelity and trustworthiness of models”
It certainly does do something. Only a fool would dismiss it entirely, as you seem to be doing. No model ever predicts the future to 27 decimal places, as you seem to be demanding it should.

Oooohhkayy! How about to 3 decimal places then? Do I hear 2? 1? How many would you say this bollux by Lacis achieved?

Ted B said:
“predicting the future, especially many decades in advance, is not science, regardless of whether it is done using tarot cards, astrological charts or “sophisticated computer models”. Such forecasts are not science because they are impossible to refute ” [at the time or soon after they are made]
—————————————————————
Well said, Ted. You have cut to the chase.

They sill say its going get warmer and dryer.
A CSIRO scientist is warning authorities not to interpret floods in eastern Australia and snowstorms over Europe and North America as signalling the end of global warming.
NASA research shows that 2010 is the hottest year on record.
Barry Hunt, an honorary research fellow at the CSIRO’s Marine and Atmospheric Research unit, says global temperatures will continue to rise even if there is another cold snap.
“Over the last century, the global mean temperature has gone up by 0.8 degrees [Celsius], and that’s the extent of the global warming, but at the same time, we also have natural climatic variation, and you don’t get one or the other, you get them both. They interact,” he said.
“I found that even up to 2040 and 2050, you can still get cold snaps under greenhouse warming.
http://www.weatherchannel.com.au/main-menu/News/Breaking-News/Floods,-freeze-not-the-end-of-global-warming–CSIR.aspx
Should not each cold snap be warmer than the last one under greenhouse warming.?

Over at Judith Curry’s climate blog, the NASA climate scientist Dr. Andrew Lacis has been providing some comments. He was asked:
Please provide 5- 10 recent ‘proof points’ which you would draw to our attention as demonstrations that your sophisticated climate models are actually modelling the Earth’s climate accurately.
——————————————————————–
Willis. What about the rest? Did he provide the other 9 ‘recent’ proof points?
Just wondering.
Douglas

Almost everyday is damning day for the AGW theorists; this is one in a long line of good articles that further discredit the “science” of A climate chnage. It really is looking like a busted flush. The question is will we have a Kings new clothes moment, or are we so far into politics that the establishment will go on and on pretending even after the crowds have all realised the kiing is naked.

Baa Humbug says:
December 29, 2010 at 8:06 am
Now, there may be an explanation for that poor performance that I’m not seeing. If so, I invite Dr. Lacis or anyone else to point it out to me.
“Dear Willis
I’m afraid your invitation, though not fallen on deaf ears, will not be accepted.
The rest of us love the way you crack that whip. It’s a veritable work of art. And you explain how you crack that whip enabling us to learn, rather like the demonstrations at agricultural shows.”
If the sentiment expressed here has become widespread then science is surely dead and maybe all of Western culture with it. Willis did not crack a whip. He merely pointed out failure where some scientist had claimed success. A genuine scientist expects failure in most everything that he/she or other scientists do. A genuine scientist has among his/her chief virtues Humility. If we expect failure most of the time, as we must, there is no harshness in pointing out another scientist’s failure. By contrast, so-called climate scientists have never experienced failure, as best as I can tell. Does anyone have a description from Mann, Hansen, you name it, of one or more failures that he experienced. I believe not. As Hansen revises his temperature data, he takes the attitude that criticism of his work amounts to Redneck Rabble Rousing and probably sedition and should be punished accordingly.
Let me crack a whip for you. Because we should assume that the scientist who created the graph that Willis discussed understands his own creation, and because that scientist claims for public consumption that his work is a success, yet that work is clearly a failure, as Willis explained, then that scientist is engaging in the chief moral error of all so-called climate science: presenting to the public work that is in some important way deficient as science yet calling it “successful science.” That is moral error. It is a great moral failing in a scientist.

Governments aren’t in the business of describing natural variation, they are in the business of imposing order. Never been any different.

Climate is to science what Vista is to operating systems.

There is no evidence there was a drop in temperature when we are talking about tiny decimal values.
There is no evidence that the drop in temperature – if real- was due to Mount Pinatubo eruption.
Besides -if we assume that temperature was well measured – why Mount Pinatubo supposedly made some parts of World colder and others hotter?
The NASA sells us crap, and Willis answers with their crap.

Theo Goodwin says:
December 29, 2010 at 1:22 pm
Thnx for taking the time to respond to my post. You say..

Willis did not crack a whip. He merely pointed out failure where some scientist had claimed success.

That’s a matter of perception. I’ve followed Willises challenges to scientists for a while now and tried to encourage them to engage with Willis. They don’t. At best one may have a go at Willis for posting at “non-science” forums like WUWT but they just don’t engage him in the substance of his articles.
TO THEM, Willis is cracking a whip (which makes a horse unused to a whip crack bolt.)
I used a whip crack as an analogy for direct no BS critique and engagement in the science presented. This is what Willis does, to the pleasure and education of the rest of us. But as you say…

“By contrast, so-called climate scientists have never experienced failure, as best as I can tell. Does anyone have a description from Mann, Hansen, you name it, of one or more failures that he experienced. I believe not.”

In other words, these people, all belonging to the same club, have never critiqued each others work as Willis does. They are not used to the whip cracking.
In fact they often support each others work pig-headedly despite numerous studies pointing out their flaws. The hockey stick being a prime example, and this post by Willis yet another.
So we are in agreement then, no?

Robert E. Phelan says:
December 29, 2010 at 6:30 am . Government work, indeed. Measure it with a micrometer, mark it with a grease pencil, cut it with an axe.

Willis,
Nice article.
Thanks.
John

I don’t think the warmists models are working!
http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/i_dont_think_the_warmists_models_are_working/

I feel sorry for the little electron people in the GISS mainframe. Not only did they have to suffer a long hard winter after the simulated Pinatubo eruption, they had to do so in the face of catastrophic climate change after it was arbitrarily decided by their gods that CO2 was the most significant forcing in their world. To compound their misery, even if they halt their simulated GHG emissions, the warming bias built into their universe will burn them all to a crisp in a few hundred years anyway. Won’t somebody think of their poor simulated children’s children?
Seriously, was the Pinatubo justification really the best they could come up with?

Winters are sure colder than predicted
http://blogs.news.com.au/heraldsun/andrewbolt/index.php/heraldsun/comments/winters_are_sure_colder_than_they_predicted#78324

Even if Dr Lacis was correct, and the GISS model’s “prediction” (shouldn’t it really be “postdiction”?) of the response to the Pinatubo eruption was accurate, what does it tell us about the accuracy of the current GISS model? Nothing. I’m sure there have been thousands, if not hundreds of thousands, of changes made to the GISS model since 1992. Dr Lacis would no doubt say that they have improved the model. I say this begs the question.
This is the dilemma eternally faced by those who model natural phenomena. The temptation to “improve” the model always takes precedence over the need to keep the model static to verify its accuracy.

I am not familiar with the details of the NASA model that was used to predict the effects of a volcano. However, even if the temperature had agreed totally with the effects on temperature predicted by the model as shown in Figure 2 as a blue line, it would not mean that the model predicts anything else with the same degree of accuracy. The question of validation of climate model designed to make long term predictions of temperature based on relatively short term temperature change from a single atmospheric event is questionable at best. Even beyond that is the weighting factors used to predict the cooling are not the same as heating from CO2. If this the best example of validation of the NASA computer model that Dr. Lacis can suggest, he should start looking for another. This is clearly a bad choice. Or perhaps there aren’t any.

GISS model seems to estimate almost flat response to strong El Nino that was going on during Pinatubo eruption. If you model the real response of El Nino that was missing when comparing this to response of 97/98 El Nino – for example – you can see that GISS model strongly underestimates the cooling that occured.
The same applies to El Chichon eruption during which the strongest El Nino of satellite era was occuring.
The real cooling peak cooling of Pinatubo is almost 1 degree.

Perhaps Dr. Andrew Lacis did not adjust the effects of the SO2 and other aerosol parameters. As a refresher, here are a few references, including how the models were tuned to historical data by adjusting the parameters for SO2.
Lindzen, Richard S. 2007. Taking GreenHouse Warming Seriously. Energy & Environment 18, no. 7 (12): 937-950. doi:10.1260/095830507782616823.
https://www.cfa.harvard.edu/~wsoon/ArmstrongGreenSoon08-Anatomy-d/Lindzen07-EnE-warm-lindz07.pdf

Introduction. “In science, there is an art to simplifying complex problems so that they can be meaningfully analyzed. If one oversimplifies, the analysis is meaningless. If one doesn’t simplify, then one often cannot proceed with the analysis.
When it comes to global warming due to the greenhouse effect, it is clear that many approaches are highly oversimplified. This includes the simple ‘blanket’ picture of the greenhouse effect shown in Figure 1. We will approach the issue more seriously in order to see whether one can reach reasonably rigorous conclusions. It turns out that one can….
(On tuning the models, page 9) “Despite this, it was still necessary to arbitrarily remove half the anthropogenic greenhouse forcing. The need to cling to the high sensitivities is readily explained by Thorpe’s insistence on policy relevance. Without high sensitivity, this would be greatly diminished. Indeed, to maintain the ominous projections, it is necessary to assume that the aerosol cancellation will soon disappear (Wigley and Raper, 2002). However, these arguments are only possible if one chooses to ignore the fact that observations are failing to display the distribution of warming that is associated with greenhouse warming….
(Page 11) “Ultimately, however, one must recognize how small the difference is between the estimation that the anthropogenic contribution to recent surface warming is on the order of 1/3, and the iconic claim that it is likely that the human contribution is more that ½. Alarm, we see, actually demands much more that the iconic statement itself. It requires that greenhouse warming actually be larger than what has been observed, that about half of it be canceled by essentially unknown aerosols, and that the aerosols soon disappear. Alarm does not stem directly from the iconic claim, but rather from the uncertainty in the claim, which lumps together greenhouse gas additions and the canceling aerosol contributions (assuming that they indeed cancel warming), and suggests that the sum is responsible for more than half of the observed surface warming.”
To be sure, current models can simulate the recent trend in surface temperature, but only by invoking largely unknown properties of aerosols and ocean delay in order to cancel most of the greenhouse warming (Schwartz et al, 2007). Finally, we note substantial corroborating work showing low climate sensitivity.

IPCC Task Group on Data and Scenario Support for Impact and Climate Assessment (TGICA). 2007. General Guidelines On The Use Of Scenario Data For Climate Impact And Adaptation Assessment. IPCC, June.
http://www.ipcc-data.org/guidelines/TGICA_guidance_sdciaa_v2_final.pdf
Aerosols: AOGCM experiments which account for both the negative forcing associated with historically observed concentrations of aerosols and greenhouse gas forcing over the same period have achieved a close correspondence of global mean temperature changes compared to observations (e.g. Mitchell et al., 2001 – Figure 10). These experiments have also been projected into the future on the basis of the assumed concentrations of sulphate aerosols, usually under the assumption of the IS92a or SRES scenario SO2 emissions profiles. The effect on climate when aerosols are included, compared to experiments forced by greenhouse gases only, is to suppress global warming. However, none of the SRES emissions scenarios shows regional SO2 concentrations as high as for the IS92a scenario, and by the end of the 21st century all scenarios show that the effects of greenhouse gas forcing dominate over the aerosol effect.

Johnston, Jason Scott, and Robert G. Fuller, Jr. 2010. Global Warming Advocacy Science: a Cross Examination. Research Paper. University Of Pennsylvania: University Of Pennsylvania Law School, May.
http://www.probeinternational.org/UPennCross.pdf
Global Circulation Model Parameters conflict, addressing tinkering with the parameters (esp. aerosols) to force the models to simulate 20th century “observations”. Since the tinkering is unique to each model, there is no way to tell which “climate sensitivity parameter” is most accurate.

(Page 29) “As recent work has shown, if the (negative) aerosol forcing turns out to be much smaller than assumed, then the ensemble of GCM’s used by the IPCC would have to have a much larger climate sensitivity (with the mean moved up a full 2 degrees centigrade) in order to remain consistent with observations. On the other hand, if the negative aerosol forcing is even larger (more negative), then the ensemble GCM’s would fail on the other side, simulating too little warming. This “mismatch” between observed and simulated 20th century warming would mean that “current agreement between simulated and observed warming trends would be partly spurious, and indicate that we are missing something in the picture of causes and effects of large scale 20th century surface warming.”
(Page 30) “That the models are essentially using aerosol parameterizations to offset variations in presumed climate sensitivity is far from an innocuous technical detail. As Richard Lindzen has explained, because a high climate sensitivity implies (other things equal) a big CO2 – induced warming, in order to have significant policy relevance climate models “cling” to high climate sensitivities, . And yet as just discussed here, the sensitivities are so high that the models simulate too much 20th century warming. To get a better reproduction of past temperatures, the models cancel out about half of simulated warming by imposing a compensating assumption about the cooling effect of aerosols. But then apparently to preserve “alarm” about the future, climate models assume that the aerosols will soon disappear. Even if the models are correct that aerosols have had a net cooling effect in the twentieth century, this series of parameter adjustments and assumptions about future changes in aerosols can hardly inspire confidence in climate models.”

(Page 30, Footnote 122) “Recent work suggests that aerosol cooling is so significant that reduction in aerosols due to pollution control and attendant solar brightening was responsible for two thirds of the warming that occurred since the mid-1980’s over Switzerland and Germany. (Philipona, 2009)”

Philipona, Rolf, Klaus Behrens, and Christian Ruckstuhl. “How declining aerosols and rising greenhouse gases forced rapid warming in Europe since the 1980s.” Geophysical Research Letters 36 (January 20, 2009): 5 PP.
http://www.agu.org/pubs/crossref/2009/2008GL036350.shtml
“Mainland Europe’s temperature rise of about 1°C since the 1980s is considerably larger than expected from anthropogenic greenhouse warming. Here we analyse shortwave and longwave surface forcings measured in Switzerland and Northern Germany and relate them to humidity- and temperature increases through the radiation- and energy budget. Shortwave climate forcing from direct aerosol effects is found to be much larger than indirect aerosol cloud forcing, and the total shortwave forcing, that is related to the observed 60% aerosol decline, is two to three times larger than the longwave forcing from rising anthropogenic greenhouse gases. Almost tree [sic, “three”] quarters of all the shortwave and longwave forcing energy goes into the turbulent fluxes, which increases atmospheric humidity and hence the longwave forcing by water vapour feedback. With anthropogenic aerosols now reaching low and stable values in Europe, solar forcing will subside and future temperature will mainly rise due to anthropogenic greenhouse gas warming.”

Apparently the EPA wishes to assure Global Warming will continue for the indefinite future (together with their jobs and power). On the one hand, they wish to reduce CO2 emissions to forestall AGW. On the other hand, they wish to reduce SO2 emissions which reduce global warming.
EPA. 2009. SO2 Reductions and Allowance Trading under the Acid Rain Program. Governmental. Clean Air Markets. April 14. http://www.epa.gov/airmarkets/progsregs/arp/s02.html
The link above provides an overview of how reductions in SO2 emissions are to be achieved under the Acid Rain Program. Below is a report of the EPA doubling down on Command-And-Control in 2010.

The Clean Air Act Amendments of 1990 set a goal of reducing annual SO2 emissions by 10 million tons below 1980 levels. To achieve these reductions, the law required a two-phase tightening of the restrictions placed on fossil fuel-fired power plants.
On July 6, 2010, the United States Environmental Protection Agency (EPA) proposed new rule, called the “Transport Rule”, which will require significant reductions in sulfur dioxide (SO2) and nitrogen oxide (NOx) emissions that cross state lines into neighboring states. The new Transport Rule will replace a Bush-era regulation called the Clean Air Interstate Rule (CAIR), which a federal court reversed, but allowed to remain in place until EPA prepared a replacement rule. This new rule applies to power plants in 28 states, including Michigan.
EPA developed this new regulation because SO2 and NOx react in the atmosphere to create fine particles and ground-level ozone in states downwind of the sources, causing jurisdictions downwind of the sources to fail to meet compliance with fine particulate matter (PM) and ozone national air quality standards (NAAQS). If a state allows activity that impairs another state to comply with NAAQS, then under the Clean Air Act it must institute plans to prevent it (known as the “good neighbor” provision).
http://www.mlive.com/environment/index.ssf/2010/07/post_31.html
— July 07, 2010, Saulius Mikalonis

Willis, thanks for another great post. Statistics is largely a mystery to me, but is it possible to adjust other parameters (such as CO2 sensitivity) in Lacis’ model, to see if doing so produces a better fit?

Alec Rawls says:
December 29, 2010 at 11:32 pm
Houston wrote: “the aerosol ‘knob’ needs to be turned down a bit.”
……..
When discussing models, parametisation and ‘knob turning’ with my students one of them commented, ” a bit like etch a sketch”. How true.

randomengineer says:
December 29, 2010 at 10:48 pm
Willis –
I don’t get what the problem is. Seems to me that what you want the model to do is know precisely what compounds were emitted and in what volumes. From there as per George E.P. Box (all models are wrong but some are useful) the model shows that it’s useful. Did it get the eruption perfect? No. Would I expect it to? No. Dr Lacis says the signs were right which I take as being on the right track.
——————–
Sure would like to know where you work random… I want to avoid products and services from your company at all costs!
If I gave a prediction or forecast to my company that was off at its peak by 100% they’d show me the door.
Here’s the crux: if the model was off 100% when modeling a fairly well understood (and relatively rare) climatic event, how far off will it be in modeling far more complicated and nuanced events? Two hundred percent? Three hundred percent? More? Less?
Here’s a simple test of the voracity of your trust in the model: run the model today and have it predict the average global temperature for 2013. Will you bet a years pay that the model will be correct?
KD, PhD Engineer and former modeler

“”””” JohnWho says:
December 30, 2010 at 8:01 am
I agree – “Prediction is hard, especially of the future.”
Much easier to predict the past. “””””
Well unfortunately, climate models don’t even predict the past. Surely if the models were any good, they would be able to recalculate the missing climate data that the EA CRU couldn’t fnd space to store, so they trashed it.
Well since they completely ignore the Nyquist Sampling Theorem, in their data gathering; there is no way they can even reconstruct the past; they can’t even correctly recover the averages.

Willis Eschenbach says:
December 30, 2010 at 12:38 pm
randomengineer says:
December 30, 2010 at 9:27 am
—————————————
Thanks, you saved me a lot of typing with your (excellent) response to random.
Random, it may surprise you to know that I have been in corporate R&D as well as product engineering and software engineering. I hold seven patents. My work is in products you can buy today, specifically in very high tech medical imaging devices.
I can assure you the requirements for accuracy in the world where the companies I’ve worked for would contemplate investing millions of dollars is much higher than a 100% error. Again I ask, where do you work?

Willis Eschenbach says:

Thanks, Mosh. If you take a look at Fig. 3 you’ll see that during the time in question, the control run varied little from zero. As a result, there is little difference between what I show, and the (projection minus control run) that you are talking about.

But, as you know, the control runs do not correctly predict the time and size of El Nino and La Nina events, which are extremely sensitive to initial conditions…i.e., essentially chaotic. Given that there was a quite strong El Nino event during that time and that we know what the general effect of such strong El Nino events are on global temperatures, the value that you have obtained for the response to the eruption is almost surely an underestimate…quite possibly a fairly significant underestimate.

That’s what Dr. Lacis said, that the performance of this model on Pinatubo is an exemplar.

Not really. The reason why Mt. Pinatubo is chosen is not because there hundreds of clean tests to choose from and this one happened to turn out better than the rest but rather because such clean tests when the predictions are clearly made beforehand (and thus no arguments of tuning, no matter how misguided can be made). It is an unfortunate fact that we don’t have an ensemble of earths to experiment with.

KD noted that the model was off by 100%, and (since you had previously said a 100% error was somehow acceptable)

Well, if you are going to demand very high precision, then you don’t need to do any tests. After all, different models have climate sensitivities varying by over a factor of 2, so you could just say right away, “I demand more accuracy before I am willing to do anything.” Of course, others might have a different point-of-view and say “Since the full range of model sensitivities points to the need to get off of fossil fuels, certainly before we use up anything near all the stores of coal that we have (let alone the more exotic sources like tar sands), we think we should do something now.” Large financial decisions are always made with uncertainties and using models that are imperfect. Do you think the economic modeling done to predict the impact of various tax and spending policies are better?
Essentially, only if one assigns infinite weight to the desire to burn fossil fuels unfettered and as cheaply as possible will one come to the conclusion that one should do nothing to lower our carbon emissions as long as there is any uncertainties about the effects (which means, of course, forever).

Well there is something that might have thrown off their calculations. From 1989 to 1992 anthropogenic SO2 emissions dropped around 15M metric tons, somewhat negating the Mt. Pinatubo SO2 injection. This happened after a 15 yr. plateau in emissions since the early ’70’s.

KD: I am not saying that climate change is not a monumental and in some ways unique challenge. However, there are potentially large costs either way. The most intelligent thing to do is not to wait until we know exactly what will happen for sure before doing anything but to hedge our bets so that we have maximum flexibility to either speed up or back off on the transformations of our use of energy (and implementation of sequestration). If you think making the transformation will be expensive if we do it gradually over the next several decades, imagine how much more expensive it will be if we continue on our orgy of burning fossil fuels at ever-increasing rates and then have to do a crash-diet once we find out that, yes, the problem is about as serious as most scientists have thought it to be.
Also, the prediction aspect is not as dire as you make it sound. It’s not like we need a weather forecast for a hundred years out. In that case, you would have errors that accumulate in time. Here, we just need (at least as a first understanding of the scope of the problem) to understand roughly how large a perturbation we would be making to the climate system. For that, all we need to understand is if the basic picture of radiative forcings governing things is correct and roughly how large the climate sensitivity is. And, the evidence from Mt. Pinatubo, along with evidence from the glacial – interglacial periods, and so forth tend to confirm this view and to point to at least a moderate climate sensitivity.

Matt G: Your statement is not quite right. You are right that for the SO2 from volcanoes, it is that which makes it into the stratosphere that has most of the effect because of the quick removal of that which stays in the troposphere. However, human SO2 (and other aerosol) emissions are emitted continuously and thus at any time there is some that is not yet washed out…and this concentration is enough to have an effect on global temperatures too. What is true is that SO2 concentrations in the troposphere are essentially proportional to current emissions, as opposed to CO2 concentrations that are essentially proportional to the cumulative amount of emissions (i.e., the integral of emissions with respect to time).
It is also worth noting that, while there is considerable uncertainty in regards to the radiative forcing due to aerosols in the troposphere, there is less uncertainty for the radiative forcing due to aerosols in the stratosphere. This is primarily because of the so-called “indirect effect” of aerosols in the troposphere due to their effect on the nucleation of liquid droplets and hence on clouds. I think another issue is that to the extent that aerosols absorb rather than reflect solar radiation, this doesn’t really produce a negative forcing when in the troposphere but do when they are in the stratosphere. (This is because the heat produced when the energy is absorbed in the troposphere can mix down to the surface.)

Joel Shore says:
December 30, 2010 at 8:50 pm
KD: I am not saying that climate change is not a monumental and in some ways unique challenge. However, there are potentially large costs either way. The most intelligent thing to do is not to wait until we know exactly what will happen for sure before doing anything but to hedge our bets so that we have maximum flexibility to either speed up or back off on the transformations of our use of energy (and implementation of sequestration). If you think making the transformation will be expensive if we do it gradually over the next several decades, imagine how much more expensive it will be if we continue on our orgy of burning fossil fuels at ever-increasing rates and then have to do a crash-diet once we find out that, yes, the problem is about as serious as most scientists have thought it to be.
Also, the prediction aspect is not as dire as you make it sound. It’s not like we need a weather forecast for a hundred years out. In that case, you would have errors that accumulate in time. Here, we just need (at least as a first understanding of the scope of the problem) to understand roughly how large a perturbation we would be making to the climate system. For that, all we need to understand is if the basic picture of radiative forcings governing things is correct and roughly how large the climate sensitivity is. And, the evidence from Mt. Pinatubo, along with evidence from the glacial – interglacial periods, and so forth tend to confirm this view and to point to at least a moderate climate sensitivity.
——————
So no example the? Falling back on the precautionary principle? Assuming there is no consequence or opportunity cost to the path you propose?
Wish there was enough wealth in the world to throw $s after the POSSIBILITY that there may be a problem, but in the world I know there isn’t. Just a bit of a financial crisis these days.
Love your last paragraph. Don’t need to project out 100 years, just a few. But the model has shown us a 100% error in just a few years. So why should we believe it? Better still, why should we base policy decisions on it?
I find your arguments to be lacking of facts and circular in nature. Given that, I’ll keep my money and my carbon fuels for now, thank you.

I still don’t see how this simulation is representative of the capability of climate model predictions.
The Pinatubo forcing change was a reduction in solar radiation of -4.1 watts/m2 (eventually OLR fell as well as we ended up with a net forcing change of -2.9 watts/m2).
Temperatures declined by 0.4C or 0.1C/W/m2 to 0.14C/W/m2
The climate models are saying +3.7 W/m2 in GHG forcings eventually results in +3.0C in temperature increases or 0.81C/W/m2.
How exactly does a short-term climate response of 0.1C/W/m2 confirm 0.81C/W/m2.
If anything, Hansen had 5 or 6 volcanoes from history which could be used to guess at a 0.4C or 0.6C decline. So, when the first GISS Model runs were done (in the 1980s) and came back with -2.0C for a Pinatubo-like valcano – they just adjusted the forcing by two-thirds to get them closer to the -0.5C (see GISS “efficacy of forcings” paper – they just changed it).
So, it does not validate the basis of the climate models. It invalidates them.

I had a random thought for your thunderstorm hypothesis Willis. Have you considered that changing radiation may change the residence time of water vapor in the atmosphere?
Hotter water vapor will rise faster, release its energy to space, and fall. This would mean that warming can actually shrink the amount of time that water vapor resides in the atmosphere.
Likewise, colder water vapor will rise slower, releasing less of its energy to space, and precipitate less.
Observations bear this idea out, but the idea of changing the residence time of water vapor hasn’t been factored into any discussion I have been a part of. Stephen Wilde’s assertions about speeding up the hydrological cycle seem to be a grasp at this concept, and are part of what made me think of this. I’d like to see what you make of this, given that you have the time/patience I lack to tinker with the models. What happens when you assign a variable to, what I assume to be constant in models, the constant of residence time for H2O that increases the residence time when colder, and decreases the residence time when warmer? This would be a great mechanism for maintaining energy in=energy out. And a new wrinkle for the man behind the curtain.