If You Can't Explain It, You Can't Model It

Sadly Vicky Pope contradicted herself within a matter of a few weeks. Just last week she said that 85% of the Amazon was going to disappear because of even modest climate change. This alarmist information came to her by way of a computer model.
http://www.guardian.co.uk/environment/2009/mar/11/amazon-global-warming-trees
The study, which has been submitted to the journal Nature Geoscience, used computer models to investigate how the Amazon would respond to future temperature rises.

Aron,
I suspect it is somewhat easier to model the impact of a pre-defined temperature change on a particular ecosystem, than it is to model what the temperature change is likely to be over time.

Steven,
But on what basis can they predict that 85% of the Amazon will disappear when most of the deforestation has been from logging and nobody can tell if the feedback effects of warming will result in drought or increased humidity. It seems they approached the subject with the expectation that a positive feedback effect would result in drought, without even considering that it might be the other way around. We could tell a model that warming will result in increased precipitation, and thus rainfall. We could also tell the model that the Amazon river will overflow because of rising sea levels and thus cause floods. Or we could get a model to give us a less alarming result.

I’m curious why the poll is present. Sure it’s a bit of fun but it is entirely useless. For one, it doesn’t have an answer I would have chosen. The closest is
“No, they are not adequate at all.” The problem is that they’ve never been tested for conformance to reality except in hindsight so their adequacy is indeterminate. The same can be said about their uncertainty. If they truly are identical models run from alternate starting points then the output indicates they are no better than a random generator or predicting the temperature next year the same as this year +/- 1C.

In a prior life I created a computer model of the human visual system as a commercial product. When tuning the engine I tweaked the sensitivities and relationships of visual primitives to predict the class of objects in the field of view. I would not make a tuning move that wasn’t understood on the basis of first principles. The further I strayed from first principles on tuning any data set, the worse the performance on other data sets.
The need to understand the process in order to model it is true only where the model is expected to work on multiple data sets.
If you will tolerate a little sarcasm:
The less you know about something the easier it is to model. Just use a neural net and the model can get very good results on the training data set. Even without a neural net it takes very little skill to tweak sensitivities and relationships to obtain good correlations with the training data set.
The GCM’s developed by the IPCC were tuned to model the climate with the data that was current at the time. And sure enough the models could predict the past. Since the IPCC models were tweaked to show that global temperature rises with an increase in CO2, the models have failed (been disproved) in the years since with falling temperatures and rising CO2.

If the underlying principals are not well understood, the model can only spit out guesswork. The effort, though herculean, is rather misdirected. Focus on doing the work that connects and follows all the paths. They did quite the job on DNA. The same amount of work needs to be done on climate before the models can be used for practical purposes.
We have had quite enough of hitting the panic button both ways: Ice Age Coming and Global Overheating.
Enough of this already.
Get back to work.

The IPCC model is a very expensive video game. Something the kids would play on Wii or Nintendo. We can ill afford for grown men to be wasting time playing with such things. The CO2 lag was already known from the Ice Cores.
Get back to work.

If this “experiment” to teach people about ocean “acidification” is anything to go by “Take a clam shell and put it in vinegar”!!!
pH vinegar about 2.5
pH seawater about 8
This “demo” exagerates by at least 5 orders of magnitude,
A real quality site

Save us from agenda funded yet, brilliant scientists and well-meaning idiots with inadequate computer models.
This whole article is a very very good analysis of GIGO. Garbage in garbage out. Well meaning idiots relying on inadequate computer models have destroyed the global economy and are hell-bent on preventing any recovery due to planned excessive carbon taxes.
Can we ever hope to return to reality based science?

Don Keiller,
This may come as quite a revelation to you, but as you neutralize an acid with pH 2.5, the pH traverses through all intermediate levels on the way to it’s final value.
Sometimes you have to think a little for yourself, though it can be painful for some.

Quote:
“The study, which has been submitted to the journal Nature Geoscience, used computer models to investigate how the Amazon would respond to future temperature rises.”
—————————–
Did the models account for the carbon used by lots and lots of petrol driven chainsaws? or the action of their teeth? It is not the (mostly) natural and modest level of climate change that is harming the Amazonian rain forests. It is the action of thousands and thousands of loggers cutting the trees down, leaving huge gaps in the canopies that do not trap evaporating water and the ground dries out so that the rivers feeding the mighty Amazon also dry up.
Mankind’s activities are indeed damaging the Amazon rain-forest, but it is NOT our production of CO2 that is to blame.

During the 1980s and 1990s, the earth warmed at a faster rate than it did earlier in the century.

I don’t think this statement is supported by any reliable evidence.

Don Keiller (11:55:42) :
Where? And what’s the point?
If burning all the fossil fuels currently known to exist fails to make the ocean acidic (it would actually end up slightly alkaline, assuming sea critters and plants did nothing to sequester any of it) what possible purpose is gained by such a demonstration?

I understand if you bundle 100 sub-prime mortgages you get a great investment opportunity.
Models without validation are just so much arithmetic without meaning. Build your models, set T0 = 1 AD and predict the 2000 years that follow. That’s what real engineers would do.

Dr Vicky Pope also contradicted herself with a MET OFFICE press release for the recent Copenhagen conference. The first sentence reads :-
“If greenhouse gas emissions continue to rise at current rates, then global temperatures could rise by more than 6C over this century”
The last sentence is slightly modified :-
“Dr Pope warns: If the world fails to make the required reductions. it will be faced with adapting not to just 2C rise in temperature but to 4C or more by the end of the century”
To me this is the very same alarmist propaganda which she has earlier criticised.

On the subject of processing power, many of Hansen’s predictions were based on very early models running on computers that were woefully underpowered compared to today’s. Yet years later he is still standing by the output of that crude technology.

John Philips,
The cooling trend which NOAA’s Isaac Held was referring to above, has been over the last decade.
Since 2002, RSS and UAH both show cooling at a rate of nearly 4C/century.
http://www.woodfortrees.org/plot/uah/from:2002/trend/plot/rss/from:2002/trend
Which model predicted that?

Slightly OT, though the question of scientific veracity versus personal belief systems and associatesd personal actions are relevant.
Is Dr. Hansen on a sabbatical?
I read that he is going to lead another demonstration – this time in the UK.
http://www.timesonline.co.uk/tol/news/uk/article5908377.ece
Perhaps our alleged Prime Minister could arrange to meet him and ask him to take the DVD’s Mr. Obama loaned him on his recent trip to Washington back the the White House video library. Brown must have had time by now to watch all of them. I assume Barry’s gift was just a holding gesture whilst he arranged to make Hansen available.
Why IS the US government paying one of its employees (one way or another) to act as a focal point for troublemakers in another country? Is this a new direction for foreign policy?

If all the Amazon rain forest is cleared it will get hotter because the sun is now shining on exposed soil. Maybe CO2 might do something as well, but the sun will heat the ground with immediate affect. In climate models forest is given the same albido rating as cities. I do not believe this is correct. I used to go gliding and became reasonably proficient at staying up by using thermals, on one case for over 6 hours. The strongest thermals were always from buildings, roads, car parks etc. The next source was open farmland. I never experienced any thermals from forest although I understand more experienced pilots can get them.
What concerns me is we will focus on fixing CO2 and at the same time continue all the other land clearing activities including draining, that will definately make it hotter. We view all these activities as local and therefore can be dismissed. When such clearances can be measured in size by using countries for scale then the effect ceases to be local.
The arguments over GW have become partisan and are not helping anyone. Is this how it was on Easter Island? Maybe they new something was not right but they cleared all the trees anyway.

John Philip,
You said that some of the models did predict the recent cooling.
What was the reason for the cooling, and what do those same correct models forecast for the remainder of the century?

Ric Werme (12:37:55) :
I don’t see the chaotic effects as being significant – we’re not forecasting the weather, we’re forecasting the boundary limits and chaotic attractors, i.e. climate.
The divergence from reality (from unknown quantities of ‘natural variation”) at present being one level of uncertainty.
The level of mathematical skill from the “proprietors” of “state of the art gcm” being another as Dymnikov 2007 observes.
” It should be emphasized that most of the scientific community concerned with climate models are generally not interested in mathematical problems and treat a model as a specific finite-dimensional construction with a specific description of physical processes, thus reducing the study of the model’s quality to a numerical experiment alone “….
…It is necessary to prove some statements for the system of partial differential equations describing the climate system’s model.
I. The global theorem of solvability on an arbitrarily large time interval t.
Unfortunately, there is presently no such a theorem in a spherical coordinate system with “correct” boundary conditions. This is not a consequence of the absence of such theorems for three-dimensional Navier–Stokes equations. The equations of the state of-the-art climate models have a dimension of 2.5 because the hydrostatic equation is used instead of the full third equation of motion.

Why IS the US government paying one of its employees (one way or another) to act as a focal point for troublemakers in another country? Is this a new direction for foreign policy?
That’s nothing. Ed Milliband said young British activists should take Direct Action to other countries to bully them against using their resources. Talk about imperialism. I am a very patriotic Brit and this kind of thing is completely out of line with post-imperial British values.

Which model predicted that?
I would be more inclined to rely upon the natural world around me, like the behavior of animals & plants, rather than on a computer model.
The flora & fauna are properly programmed, the computer models are at best guesswork based on incomplete information. They are in thier infancy.

John Philip (12:35:05) :
“Global climate models are extraordinarily useful tools, and among other things have successfully predicted the rise in temperature as greenhouse gases increased, the cooling of the stratosphere even as the troposphere warmed, the increase in the height of the tropopause, polar amplification due the ice-albedo, and other effects, and greater increase in nighttime than in daytime temperatures, and the magnitude and duration of the cooling and the water vapour feedbacks caused by the eruption of Mount Pinatubo. ”
I am always amused to read these kinds of claims, only to find that it’s just another climate hindcast. That is, you know the answer before you run your model. Nothing wrong with that, except it is NOT a prediction! It does allow you to tune you model to get perfect agreement with the past (imagine that)…
For those who want a more sober assessment of the predictive skill of modern climate models should read this:
http://climatesci.org/2008/11/14/are-multi-decadal-climate-forecasts-skillful-2/

Steven Goddard (13:53:32) :
John Philip,
You said that some of the models did predict the recent cooling.
What was the reason for the cooling, and what do those same correct models forecast for the remainder of the century?
You beat me to the question, Steven. The second and third questions then are, which output is correct and how do we choose?

John Philip (12:35).
I wanted to take a look at one of the references you gave (Lucia). Most of it is outside my area of expertise. But the author also said this.
“However, it is worth nothing that at a significance level of 90%, the best estimate of the underlying trend in GMST based on the average of 38 runs is inconsistent with the observed trend. Using the language of the IPCC, the result of this test suggests we should have very low confidence that model projections based on this sort of multi-run average are correct.”
“So, what we are finding is that if I try hard enough, I can currently hunt around for methods of averaging that fail to falsify the models.”
This sounds inconclusive. But I am willing to try other references. (or be corrected).

With advance apologies Hope this gives a chuckle or two.
Not so long ago I began working on computer models using my old, but trusty Commodore PET with the aim of predicting exactly of what the moon is made.
As it turns out the models, LCM’s [Lunar Cheese Models] ran very well., but with some differences in output, depending on the milk type, temperature, salinity, and bacterial type used. Sometimes the output indicated the moon was made of Swiss cheese – which fit well with the observed cratering; possibly from earth sourced atmospheric bleed-over of CO2. Other times the model runs suggest a composition closer to double cream Brie, which, with minor solar irradiation would flow and form the observed maria. Other runs are consistent with a sharp crumbly English cheddar [aged at least two years] resembling the lunar mountains.
But, puzzlingly often, the LCM output indicated a new cheese with a very foul “runaway smell” index. To this runaway smell cheese I have tentatively assigned the folk taxon Moon cheese.
Now, after running these models many times, I am absolutely sure they yield the correct basic chemistry of the moon — in spite of real data returned from Tranquility Base through Taurus-Littrow.
No, before you ask, I will not make public the data input for these models or how I may have adjusted them to get the proper output. Nor will I answer questions about the model’s accuracy. Just trust me.
And now, given that my models are correct, I intend to lobby Congress and the executive branch to immediately stop all attempts to return to the moon as any large scale lunar commerce would represent a dire threat to earth based cheese makers. If successful in lobbying, I shall submit proposals for grants for further research in Moon cheese.
The LCMs also predict that Moon cheese will occur from time to time on the earth itself and probably in ever increasing amounts. We should, therefore, take immediate and strong action to prevent this from happening as the runaway smell could easily make the earth uninhabitable within the next few decades. Curbing the runaway smell output might well be enforced by requiring every citizen to buy “cut the cheese credits” [CTCC’s]. The obvious benefits of CTCC’s to all mankind are self-evident.
We have at most 5–7 years before reaching the tipping point for this phenomenon Many readers may have doubts about the seriousness of the imminent runaway smell problem, but let me suggest that if you have ever been “mooned,” you probably recognize the smell whereof I write. So keep careful watch and do your best to avoid the Moon cheese! And watch where you step too.

@Mike T (12:51:52) :

“Just a shame that in the UK’s Kings North power station vandalism trial only one view was on show. The prosecution wasn’t about to disturb the consensus and put up anyone to dispute Mr Hansen’s views.”

I agree, it would have been great to have a well-spoken, knowledgeable expert to provide balance.

Paul S,
Yes – the logic seems to go.
1. The IPCC uses a wide range of model outputs, ranging from little warming to a lot of warming.
2. Because the measured temperatures were close to some of the lower forecast models, that validates the higher forecast models.
3. Thus we can expect 6+C warming this century
I predict that the stock market will either go down, up or stay the same next week. Those are my three scenarios, and I’m sticking with them through thick and thin.

TonyB said:
“As a Brit I really resent the fact that a govt employee of a friendly power can be sent to its major ally to cause trouble and try to tip us into the dark ages through denying us much needed energy. Can’t you control the guy?”
Many of us Americans certainly resent it to. Hansen is an embarrasment to science, to NASA, and to the U.S.A.
I have to say…when the cat left, the mice started to play.
As dislikable as the Bush Administration was to many in the world, notice Hansen did not really start going hog-wild, until AFTER the current president took over the White House.
Why does Hansen do it? Because he knows he can.
But we share your sympathies. Fire him….and TRY him, if necessary.
Try him for what? MALFEASANCE, INCOMPETENCE, and WANTON DISREGARD FOR PUBLIC OFFICE.
History will not look too kindly of him….or his chums Gore or Holdren.
But they are one in the same: politically driven-ideologues who squelch free thought and TRUE scientific discipline.
The shameful “American Inquisition” in action!
The fact that the climate models have failed to even extrapolate a warming trend in the past 10 years, and still, in spite of that, where they not backing down…can only mean one thing: megalomania.
Too bad there is not a model to accurately predict the behavior of politically-driven scientists as to what they might do next!
Latest Hansen Short and Long-range Forecasting Outlook:
HANSEN POLITICAL DEVIATIONS ABOVE NORMAL ARE APPROACHING RECORD MAXIMA SINCE RECORDS HAVE BEEN KEPT.
PROTEST IN THE U.K. HIGHLY LIKELY AND IMMINENT. OTHER PROTESTS ARE POSSIBLE IN THE LONG-RANGE, BUT THE EXACT TIMING AND INTENSITY OF THOSE HANSEN APPEARANCES WILL DEPEND UPON OTHER FORECASTING VARIABLES DOWNSTREAM IN THE LONG RANGE AND GENERAL MODEL AGREEMENT AFTER SUCH EVENTS HAVE MATERIALIZED.
THIS IS A HIGHLY VOLATILE AND UNSTABLE SITUATION…STAY TUNED TO YOUR LOCAL WUWT FORECAST FOR DETAILS IN THE EVENT A WARNING IS ISSUED….
Chris
Norfolk, VA

Correction “true scientific DISCOURSE.” Although I guess the word “discipline will work LOL

sod – am I right in thinking that scenario A is the one in which CO2 emissions continue to increase unabated (“BAU”), scenario B is for CO2 emissions stabilised at around 1990 levels, and scenario C is for CO2 emissions drastically cut?
The observed temperatures are closer to scenario C than either of the others, but where are the observed CO2 emissions?

Tamino thinks that the models forecast rapid warming since 2002.
http://tamino.files.wordpress.com/2008/03/rahmstorf2.jpg

sod (14:33:18) :
http://www.realclimate.org/images/Hansen06_fig2.jpg
but you knew that, of course?!?
But scenario’s A & B are the ones promoted. Perhaps we should dismiss those scenarios for scenario C, seeing as they are currently, note, currently, closest to reality.

Well, call me simple minded or whatever, but when the amount of experience, time, money and people involved in near-time weather forecasting cannot accurately predict what the conditions are going to be 5 days from now, why should I trust our Climate experts to be accurate 10 – 20 – 50 – 100 years from now? I know a lot of the experts claim that Weather forecasting and Climate Forecasting are different things entirely. Well, Math and Physics are also separate, but if you can’t do the math accurately you aren’t going to answer many physics questions.

Question for Anthony possibley concerning models. I believe that it was almost a year ago that you published a letter regarding the Aqua Satellite results. As I recall, they were not being released pending further peer review since the findings were at odds with current thinking [models?]. Any update on the status?

JohnG, In my experience giant code is often not “just bloat” — it’s hacking. Like for instance “if the surface of the ocean at the tropics freezes force fix the data…” That’s the kind of thing I’d be looking for if I audited the code. I agree that the code really *should* be simple to have any hope of validity.

I have always had a few questions regarding the modeling processes used by the IPCC, and although these questions are argumentative in that they reveal my opinion about the usefuness of climate models, perhaps someone here is in a position to address the factual bases for these questions or explain why the questions might be misplaced.
Based on a very cursory reading of the latest IPCC report, it is my understanding that the conclusion of a causal effect between GHGs and warming is premised in part on a finding that exising climate models cannot simultate current climate trends without a substantial CO2 warming effect. Due to the chaotic nature of the climate system, and the unknown nature of what initial conditions to use in the models, a model is “run” many times with different intial conditions to produce a range of climate trends, and the reasoning is that, because none of these model runs show the existing warming trend without the modeled CO2 sensitivity, then it is reasonable to conclude that the existing warming trend in the real world is caused by CO2.
My first question is whether I have fairly summarized both the modeling process of the IPCC, and the reasoning behind it’s finding of a causal effect between CO2 and warming; because if so, this logic seems flawed. All this exercise demonstrates is that the models used by the IPCC require a substantial CO2 contribution to temperature in order to reasonably fit known climate trends. Nothing more. It certainly does not demonstrate that NO climate model could be constructed that both reasonably fits known climate data and uses an insignificant sensitivity to CO2. In other words the premise that models A, B, and C cannot simulate climate trends without relationship 1 does not logically support the conclusion that relationship 1 holds true in the real world system that the models A, B, and C attempt to simulate. Models A, B, and C may be simply wrongly constructed in one or more respects.
This leads into the second question. Has anyone actually tried to construct a model that has little or no CO2 effect, and then spend as much effort tweaking it to best fit past and current climate, as has been spent tweaking climate models that DO assume substantial warming.
My last two questions are a little more general. What possibile utility is there in modeling a relationship that cannot be physically measured, either directly or indirectly, e.g. the temperature response of the Earth as a function of CO2 concentration? If you don’t have the ability to measure a physical system at a level of detail that you need to perform a task, why would someone think that this deficiency could be overcome by simply modeling the system at the desired level of detail and testing the model against the things you can measure?
Finally, given that a computer does nothing more than what the programmer instructed it to do, how can merely running the computer model tell you something that you did not already know or assume about the system modeled? I can accept that a computer model can be highly useful as a shortcut in performing tasks too complex to be reliably done manually, once it has first been established that the computer model is accurate with respect to the specific task at hand. I have a much harder time believing that a computer model can TEACH you anything about the system modeled, particularly with respect to modeled relationships that can’t be independently verified apart from the simulations.

John Philip,
Given the seven year drop in temperatures, I take it that you are predicting a rapid rise over the next year or two to get back on the scenario A curve?

“… it would not get much better until they had supercomputers 1,000 times more powerful than at present.”
The “we just need more computing power” line is both tired and false. Increased computational power does not convey increased understanding.

I wonder what the systemic error of the model is given the very large elements they use and what is the systemic error due to feedback of the errors?
My guess is that its very, very large and the feedback completely dwarfs any meaningful analysis.
I know the current numerical models used by NWS and others suffer from tremendous feedback issues.

“when . . . people involved in near-time weather forecasting cannot accurately predict what the conditions are going to be 5 days from now, why should I trust our Climate experts to be accurate 10 – 20 – 50 – 100 years from now? I know a lot of the experts claim that Weather forecasting and Climate Forecasting are different things entirely.”
Lets say that I have a very weak, repetitive, audio signal that I’m sending across the country. On it’s path, that audio signal is subject to quite a bit of random noise. When received, over short intervals the signal is going to represent mostly the random spurrious noise, and reconstructing the repeating pattern will be almost impossible. With sufficient time, however, the original signal can be reconstructed because it’s pattern holds over time while the random noise cancels itself out. Once reconstructed, you can acurately predict the up and down trends of the signal so long as they are avereraged over a sufficient interval, but accurately predicting any instantanous point will be impossible.
Notice in this example, however, that the source of the signal and the source of the random noise are mathematically uncorrelated. This is what permits you to separate the short term random noise from the long term repeating signal. The same physical phenonena that produces weather however, produces climate. In fact, weather is nothing more than the instantaneous manifestation of climate. Those who argue that long term climate is predictable even though short term weather is not, are essentially making an unstated assumption that the chaotic nature of the earth’s climate system fades out over frequencies longer than four decades or so.
Which side of the argument you take depends on how reasonable you think this assumption is. I think it’s a lousy assumption. For example, when I look at long-term climate reconstructions, I don’t see any pattern in the various climate optimums and minimums. The standard deviation for the length of ice ages/interglacial periods, from eyeballing these reconstructions, also seems a lot longer than four or five decades. All of this seems to indicate to me that there is a lot of randomness in the Earth’s climate system that is not removed by taking averages over a period of decades.

The less you know about something the easier it is to model.
That’s very encouraging. Now that my solar system orbital simulation model is working tolerably well, and I have a planet Earth in it spinning once every sidereal day, and orbiting just about once every year, I’m thinking that I may extend it to include the terrestrial atmosphere, which I’ll divide up into layers in some sort of grid. Knowing the thermal conductivity and heat capacity of air, sea, and land, and the incident solar radiation at any point on the planet surface, and the heat losss from the planet interior, I’ll be able to work out the conductive heat flow vertically to outer space at absolute zero, and horizontally through the atmosphere and ground.
I’m not sure at the moment what to do about air flows using this grid system. I’m wondering if, instead of having a fixed rectangular grid, I might have mobile air masses which would ‘jostle’ with each other as they expanded and contracted, no doubt forming warm and cold “fronts” surging to and fro, and spinning clockwise and anticlockwise under the influence of coriolis forces, and very likely northern and southern “jet streams” as well.
That should all be working by next Thursday. Then I’ll add in clouds and precipitation. I’ve heard this is difficult to do, but I can’t see any big problem there. As my mobile air masses jostle with each other, the warmer lighter humid ones will float to the top of the atmosphere, and will turn white as the water in them condenses into clouds and rain. I expect I’ll have cirrus and stratus and cumulus clouds appearing shortly after that. And I’ll be able to make weather predictions for the next few days, although obviously not quite as accurate as the Met Office’s (or perhaps more so?).
It should be early April by the time that’s working. Looking at climate over a long period of time should be straightforward. I’ll just have to leave the laptop running all night under my bad where Twinkle can’t find it and started treading on the keyboard like she enjoys doing when I’m working on it.
Mid-April now. And then there’ll be the final tweak to get the CO2 and global warming working, maybe just by decreasing air conductivity a bit, or boosting solar insolation by the same fraction.
Finally, in early May, I’ll release the results of my GCM to the world in a series of increasngly panic-stricken press releases that will describe how all my mobile air masses have been jostling and bumping into each other to produce the entirely new and hitherto unforeseen phenomenon of Global Swelling, which is what happens when warm sticky air masses form a “traffic jam” around the equator, and pile up higher and higher on top of each other, before rolling downhill towards the poles again, very likely destroying entire civilizations in the process – unless governments Do Something About It Before It’s Too Late – like buy me a newer and faster laptop with WiFi and BlueTooth and all the other latest fancy trimmings.

My first question is whether I have fairly summarized both the modeling process of the IPCC, and the reasoning behind it’s finding of a causal effect between CO2 and warming;
You have.
This leads into the second question. Has anyone actually tried to construct a model that has little or no CO2 effect, and then spend as much effort tweaking it to best fit past and current climate, as has been spent tweaking climate models that DO assume substantial warming.
All attempts to produce numerical predictions of future climate are models. I think what you are asking is, are there Global Climate (Circulation) Models that have little or no CO2 effect?
The simple answer is we don’t know, because models are proprietary and only selected model runs are published.
However, with reference to your question 1, this means the IPCC’s case is built on an unverified and unscientific assumption. Namely, the published runs are representative of all possible runs.
What possibile utility is there in modeling a relationship that cannot be physically measured, either directly or indirectly, e.g. the temperature response of the Earth as a function of CO2 concentration? If you don’t have the ability to measure a physical system at a level of detail that you need to perform a task, why would someone think that this deficiency could be overcome by simply modeling the system at the desired level of detail and testing the model against the things you can measure?
The IPCC used to be upfront about the fact the models are wildly wrong on almost every climate metric except temperature. They then bizzarely concluded we can trust the model’s temperature predictions.
Anyone can see that the reason they get temperature right (when hindcasting known data) and all other values wrong, is the models are tuned to the temperature data.
Finally, given that a computer does nothing more than what the programmer instructed it to do, how can merely running the computer model tell you something that you did not already know or assume about the system modeled?
You are correct, a computer model doesn’t tell you anything you don’t already know or had assumed.
How the computer models work, is they iteratively process datasets with the output of one iteration becoming the input of the next iteration. Each iteration being a time period.
What computer models allow you to do in theory is to produce predictions of much greater accuracy.
There is no empirical evidence that climate models do in fact produce more accurate predictions than for example, drawing a line on sheet of graph paper or the computer equivalent.
The IPCC’s belief in the temperature predictions of the climate models is purely faith without any scientific basis.

I am curious as to whether one of the modelers has recalibrated his model to the now 10 years of stagnation in warming.
If this has been done, I’ve not heard about it.
If not, then why not? (Other than, of course, it would mean the sensitivity of CO2 would need to be cranked way down!)

How can someone simultaneously say that natural variability is strong enough to supress the climate signal from GHGs for possibly the next 30 years, while also maintain that the climate signal from GHGs has been observably distinguished over natural climate variability in our temperature record. In the mid to late 70s, the earth was winding up a cooling trend, and the case for global warming was based primarily upon the large temperature increases in the 30 years since then. If, despite the increase in annual CO2 emissions, global warning is not yet strong enough to counteract natural climate cooling in the 30 years going forward, then how can anyone look at the past 30 years and conclude that any particular amount of the warming trend of the last 30 years was or was not natural? Has somebody proven that the claimte naturally cools more strongly than it warms?
In my mind, this is an admission that there is no proof of manmade global warming that can be taken from the Earth’s temperature record.

@kurt (17:29:07) :

We flogged away at this question a few days ago on another thread (see WUWT 2/19/09, http://wattsupwiththat.com/2009/02/19/when-you-can’t-believe-the-model/ ) with two camps emerging: One, computers cannot do any more than their human programmers tell them; and Two, computers can determine things no human ever could do. I am firmly in both camps, having written and tested both sorts.
The theory and practice of Artificial Intelligence holds that there exists several classes of problems in Camp Two for which there are no known solutions, some are so large that even a computer the size of a galaxy would require millions of years to solve.
A more tractable example of Camp One is where no direct solution exists to a given problem, hence trial and error must be used. Further, the number of iterations can continue for a very long time with successive results improving only in the very small decimal places. Therefore, some sufficiently small difference is allowed between iterations, and the answer is declared at that point. Some problems have sufficiently numerous variables, and complex calculations that they can only be solved iteratively. Humans can do this, but it takes a very long time and is prone to calculation errors
A simple analogy from engineering is the heat loss from the surface of an insulated pipe carrying a hot fluid, calculated by determining the temperature gradient through the insulation and the wall of the hot pipe. One can establish the internal temperature of the pipe, for example, carrying hot steam at 900 F. The pipe wall thickness is known, and its thermal conductivity is also known based on the type of material. One also knows the temperature of the surrounding air, for example it may be 40 F. The thickness of insulation is known, and its thermal conductivity is known.
To solve this, one makes an initial guess for the temperature at the outer edge of the insulation, then solves the various heat-balance equations, including radiation heat losses. A calculated temperature at the outer edge of the insulation results, usually not the same as the initial estimate. One continues to input the new temperature, re-solve, and check to see if the old temperature is sufficiently close to the new temperature.
Now, extrapolate this simple problem into an atmospheric model, where the atmospheric volume is divided into a grid of thousands of cells, each cell having three dimensions. The heat transferred from one cell to another, in all three dimensions, must match the heat received from other cells.
Temperatures are a measure of heat, so the model (had better) solve for temperature. Further, the properties of the air in a cell change with temperature, as the volume increases as temperature increases. This creates a mass-transfer that must be properly calculated and solved iteratively. Further, there are moisture issues, or humidity, with rising vapor from oceans entering the appropriate cells.
There is heat input from the sun, which varies not only by the time of day, but with the seasons as the earth orbits and the axial tilt changes with respect to the sun. The day-night changes in heat input also are important. Clouds act both to reflect daytime sunlight, and as a thermal blanket at night.
The iterations must continue for some time because we are interested in very small changes over very long time periods, so solving to 1 degree C probably is not going to pass muster.
Other considerations are water vapor condensation as rain releases heat in upper cells, and rain falling to the earth that may absorb CO2, or it may evaporate somewhat as the drops fall through less humid air, or it may fall to earth. Also, the water droplets may freeze and fall as sleet or hail, or they may initially form as snow. Albedo effects from snow and ice are of course important.
One can appreciate that this gets fairly complicated, thus the need for a computer to solve all the equations. It may be possible that humans could solve the equations, but the organization and time required would be immense.
From my readings on the subject, not all of what I just described is modeled, and there are other important things I have not included. One such thing is CO2 levels increasing with time. Also, methane levels increasing. Also, dust or smoke from desert winds or cooking fires. Also, aerosols from both natural sources, such as volcanoes, and man-made sources. One effect from warming is that frozen methane hydrates may thaw and enter the atmosphere. The recent stories on methane bubbles in the Arctic are on point.
I don’t know if this helps any, but it is how I view these models, and remind myself that these modeling guys may be making heroic efforts and good progress relative to where they were 10 years ago, but they are really kidding themselves, and especially elected officials, with any predictions of the future.

FatBigot,
Ah yes, thanks for that link. A good read! And now it makes perfect sense why an opposing view would not be heard. I must have missed that part, if it was indeed reported.

A couple of points to keep in mind.
1. Had 2007 been the hottest year on record as the Met Office and Hansen predicted, it would have been cited as proof that the models were correct. Instead, 2007 saw temperatures drop by more than 0.5C and was discounted as “natural variability.”
2. Looking at the graph of the last 30 years, one would have to have a very active imagination to see 6C of warming in the next 90 years.
http://www.woodfortrees.org/plot/uah/from:1978/plot/rss/from:1978/plot/uah/from:1978/trend/plot/rss/from:1978/trend
Defenders of the AGW faith attempt to bury these inconvenient truths in statistical games, but we are not as gullible as they are hoping.

kurt,
From my understanding all the models employ a “forcing” which is a positive number that says how much T changes when [CO2] changes. The main function of individual models is just how minor perturbations about that trend appear. The prediction of rising T is simply an expression of the assumption that “forcing” is positive, not zero. So, yes, the ouput is just the assumption in disguise.

Those climate computer models aren’t proper models. This is a model.
Some bright folks are working on golf ball design and how the dimples affect air flow around the ball, and are trying to create accurate computer models of a golf ball in flight. Working out the solution to these equations — even on the fastest personal computers today — is not feasible since it would take more than 15 years of computing time just to get a glimpse of the flow around the golf ball for a fraction of a second.
Now all we have to do is find out all the climate drivers, then plug them into a computer model, hit the “Run” button and sit back and wait…

kurt, G. Alston, and others:
You seem to have some misconceptions about the climate models.
1) CO2 sensitivity is not an input parameter in the models. The CO2 sensitivity is determined from the RESULTS of the models.
2) The GISS model itself, along with the inputs and results of their model runs, are freely available at the GISS website. (I don’t know about how open other climate models are.)
3) The climate models were not “written from the ground up to simulate climate response to CO2”; they were written to simulate the climate change from ANY forcing- solar, albedo, aerosols, ozone, etc…, not just CO2.
4) Many models have been run both with and without anthropogenic CO2 (there’s a section about it in the IPCC report). Needless to say, the two scenarios yield very different results.

Reed Coray (19:53:28) :
Henry Phipps’. I have a question. Were the birds “purple” before or after they flew into the cold north?
Reed, the birds were purple, the science is settled, and we have no time for debate about this.
What IS distressing is that parts of the ornithologists who observed the birds in the blizzard have also turned persistently purple.Looks to be a rather tame Christmas party at the Department of Ornithology this next holiday season.
Best regards, Henry

deadwood (18:34:45) :
I am curious as to whether one of the modelers has recalibrated his model to the now 10 years of stagnation in warming.
If this has been done, I’ve not heard about it.
If not, then why not? (Other than, of course, it would mean the sensitivity of CO2 would need to be cranked way down!)
http://www.nature.com/nature/journal/v453/n7191/abs/nature06921.html
They added the PDO to their GCM to get
“Our results suggest that global surface temperature may not increase over the next decade, as natural climate variations in the North Atlantic and tropical Pacific temporarily offset the projected anthropogenic warming.”
It is called :” moving the goal posts” . Or,” the pot of gold is always at the end of the rainbow”.

kurt,
“Could the results be used to better tell you what the thermal conductivity of the pipe wall is, if it were not possible to meause that thermal conductivity in the real world?”
Actually, I believe the answer to that is yes, but only if one is able to measure the outer wall temperature, that is, the edge of the insulation exposed to the atmosphere. If one is unable to measure that outer wall temperature, the problem becomes indeterminant. There would be too many unknown variables, and not enough equations.
Part of the GCMs’ problem is no one can truly test or verify the models, as we cannot easily add 100 ppm of CO2 to the atmosphere without waiting for a good many years, and we cannot cut 50 ppm CO2 from the atmosphere very easily, if at all. These changes in CO2 are the step-tests that should be conducted to determine the physical responses to a change in a control system, and thereby verify the models. Therefore, every modeler is guessing, based on some estimates of how laboratory science scales up in the large atmosphere. I refer, of course, to CO2 absorption of certain wavelengths of infra-red radiation from the earth’s surface, and subsequent re-radiation.
Similarly, it is difficult if not impossible to perform step-tests for albedo changes (zero polar ice), cloud cover (zero cloud cover and 50 percent of the earth), volcanic gaseous and particulate emissions (like babies, they keep their own schedules), and so on.
The skeptics have devastating claims as, for example, Steven Goddard among others, with the evidence that none of the GCMs predicted the current cooling trend that is reported by the four major measurements. Such cooling should be impossible due to increasing levels of CO2, if the GCMs are correct. Cooling is predicted from major volcanoes, and decreases in CO2, neither of which occurred.
This fact alone should be hammered home to the elected officials who are drafting climate change legislation.

All I can say is AMEN and as an engineer who has done incredibly simple mechanical models covering minutes of simulated time, observing the errors involved in even the simplest and shortest of runs, it strikes me as incredibly amazing and arrogant that climate modellers think they have an accurate climate model for 100 years out. The models can help you do many useful things but it is not a crystal ball; it is not soothe-saying proxy.

It seems most commentators on this site have the mistaken impression that a model is only useful if it can provide accurate predictions. However, they are missing an important aspect of the modeling endeavor. In many cases the purpose of a model is not so much to make accurate predictions as to provide a means to test the basic assumptions upon which the model is based. In short, a model provides a means to relate one set of observables to another set of observables and to understand these relationships. The model also provides a means to test the limits of these relationships (or assumptions) and to determine when they break down.
In this sense much of the climate modeling work has been hugely successful in that scientists have been able to rule out some unimportant relationships and have greatly expanded our understanding of both climate and weather. They have also been able to test various scenarios and make predictions. Of course if some of the underlying assumptions are incorrect their predictions will be incorrect, but this is still a valuable exercise in that it provides a way to evaluate their assumptions and later analyze which of those assumptions broke down.
Unfortunately, most people don’t grasp the fundamental value of the modeling exercise in expanding our understanding of a phenomenon. Because of this, there is tremendous pressure on modelers to produce predictive models. Unfortunately, this can often lead the less careful modelers to overestimate and overstate the abilities of their models and to overlook or even hide known flaws. Furthermore, the situation becomes exacerbated when the media or government officials take modeling results out of context and try to formulate policy based on a hypothetical prediction.
The bottom line is that models are extremely valuable tools even when they are not predictive. However, it is critical to understand their limits and to be very cautious when applying a model’s results outside of these limits.
I think many climate scientists are doing a great job in developing their models. However, it seems to me that some experts in the field are a bit too confident, especially when we all know there are severe limitations for modeling so many incredibly important phenomena, such as cloud formation, humidity, aerosols, etc…

I would like to coin a new word – “weathersuckers” – anyone who thinks they can predict weather or climate beyond a few days into the future. It has a nice ring to it don’t you think?
Then of course there are the “coolweathersuckers” (CWS) and the “warmweathersuckers” (WWS). You know who you are 🙂

Roger Sowell (18:58:49) :
The theory and practice of Artificial Intelligence holds that there exists several classes of problems in Camp Two for which there are no known solutions, some are so large that even a computer the size of a galaxy would require millions of years to solve.
Reminds me of Hitch hikers guide to the Galaxy. The question posed was “What is the meaning of life” 🙂

You’re correct to say that models are more complex than they are sometimes presented to be. Gore simplified the message to highlight the importance of carbon emissions, but the truth is that increasing anthropogenic CO2 and natural cyclicity of insolation each affect year-to-year variations in climate and the weather we experience.
That’s pretty simple to understand. The addition of a steadily rising curve with a lower amplitude sinusoidal signal produces a stepped but broadly rising profile — in other words, a general warming trend with broadly predictable (but lesser scale) oscillations around that.
Here are a couple of references which amply illustrate that point:
http://www.realclimate.org/index.php/archives/2004/12/just-what-is-this-consensus-anyway/
http://greenfyre.wordpress.com/2008/12/03/global-warming-is-over-once-every-decade-or-so/
The truth is that the cold weather which you highlight so assiduously and correctly on this site is entirely on schedule and as predicted by any scientific model which takes account of those two processes.
I’d warmly congratulate you for reminding us that insolation effects must also be considered in climate modelling, but I’d advise strongly against any kind of hubris that a few recent and impressive spells of cold weather contradict a general warming trend. Because they really don’t.
Kind regards from London.

SemiChemE (00:12:18) :
I think many climate scientists are doing a great job in developing their models. However, it seems to me that some experts in the field are a bit too confident, especially when we all know there are severe limitations for modeling so many incredibly important phenomena, such as cloud formation, humidity, aerosols, etc….
I think you are being too kind in a situation that requires as much ruthlessness as that shown by the politicized AGW crowd as regards the repercussions of denying energy to billions of people mainly in the third world.
Climate scientists who do not speak up at the misuse of modeling are equally guilty as the ones that are pushing modeling as modern day prophecy, so why treat them with gloves? It is not the models that are at fault, but the use made of the outputs.

Funny irony:
“Edward Lorenz continued to be active in his work well into his seventies, winning the Kyoto Prize for basic sciences, in the field of earth and planetary sciences, in 1991.”
http://en.wikipedia.org/wiki/Edward_Norton_Lorenz

roads — That’s pretty simple to understand. The addition of a steadily rising curve with a lower amplitude sinusoidal signal produces a stepped but broadly rising profile — in other words, a general warming trend with broadly predictable (but lesser scale) oscillations around that.
Common M.O. of the AGW adherent is to show a graph just like this. I don’t think you understand what skeptics are saying.
The graph doesn’t show anything more than correlation. Chances are you can plot temps against land use and population growth and get the same curve. But does this imply that people are raising the temps via spewing gases or are the temps a proxy for land use changes and the CO2 isn’t part of that equation?
Also, how much of that rise is natural vs the work of man? Much is made of the ability to detect the fossil fuel signal in that CO2 plot via analysis of isotopes. And yet this isn’t trumpeted far and wide. Why? because it’s 3%.
The graph may not be telling you what you think it is.

Roads (04:10:24) :
The truth is that the cold weather which you highlight so assiduously and correctly on this site is entirely on schedule and as predicted by any scientific model which takes account of those two processes.
I’d warmly congratulate you for reminding us that insolation effects must also be considered in climate modelling, but I’d advise strongly against any kind of hubris that a few recent and impressive spells of cold weather contradict a general warming trend. Because they really don’t.
There is no one contributing to this blog that would refuse the warming since 1850 or so. Nobody. What people are refuting are the Anthropogenic as in AGW. Even if Gaia had not had a sense of joke, or irritation at the hubris of AGW, and had not sent a negative PDO, the A in the IPCC models is nonsense.
1)The trends in the tropical troposphere did not warm more than the surface during the years of warming.
2) CO2 lags temperature by 800 years long term and 6 to nine months short term, again even during the warming years.
3)The humidity did not play ball as the models predicted, even during the years of warming.
In addition during the years of stasis CO2 is merrily climbing and is unable to budge the PDO, let alone stop the next ice age as Hansen had the hubris to suggest a while ago.
So we do have a good PR from PDO, as AGW had one when the PDO was warm. So?
have a look at the real prophecy:
http://en.wikipedia.org/wiki/File:Vostok-ice-core-petit.png
and look at the clockwork precision of ice ages, every 100.000 years recently. We are at a flat top that is lasting much longer than other transitions, which is oscillating within 1C from a stable temperature. This will not last. That is the true prophecy, that there will be another ice age. In a few years, a thousand or more, but that is the real danger for humanity where thought and resources should be focused. The flat top shows that we will be playing with tolerable temperatures, until the grand slide starts.

It is true that weather and climate patterns, like patterns of movement in complex economies, have so many variables that computer models to predict future trends do not work for long periods of time.
On the other hand, from what I have read, we have some strong indications that global warming is real. Sea level is slowly rising, and the melting of arctic ice is making life harder for polar bears. They may be in danger of imminent extinction. I have also read that whales are starting to starve to death because of the death of organisms at the bottom of their food chain.
Since I live in a coastal city (Long Beach, California), I am particularly concerned about the rise in mean sea level. From what I have read, glaciers in Switzerland and the Andes are receding, threatening hydroelectric-generation systems in Switzerland and fresh-water supplies in South America. (Changing patterns of rainfall are also threatening fresh-water supplies in Southern California.) And the rise in sea level also is threatening to flood small, low-lying island nations in the Pacific.
While we know that mean sea level is rising, we don’t know whether it will rise by one foot by 2100 or two or three yards (this apparently depends on the how fast the glaciers of Greenland and Antarctica melt).
Any rise at all threatens the continued viability of New Orleans, for example, parts of which lie below current sea level. Right now, it seems to me that it is foolish to try to rebuild New Orleans because it is highly likely that the city will be flooded before the beginning of the next century.
Harleigh Kyson Jr.

Didn’t have a chance to check other posts to see if this has been referenced:
…a new study by the University of Wisconsin-Milwaukee could turn the climate change world upside down.
Scientists at the university used a math application known as synchronized chaos and applied it to climate data taken over the past 100 years….Now the question is how has warming slowed and how much influence does human activity have?
“But if we don’t understand what is natural, I don’t think we can say much about what the humans are doing. So our interest is to understand — first the natural variability of climate — and then take it from there.

@ G Alston (18:16:52) :

That’s the thing. These models were written from the ground up to simulate climate response to CO2. It’s what they do; why they exist. That anyone is surprised when the answer to the question is CO2 still amazes me.

Exactly! I have often posited that these models produce warming because that’s exactly what they are programmed to do. The models don’t test the AGW hypothesis, they just illustrate how it might work, given various scenarios.

G Alston:
“The anthropogenic contribution of CO2 is 3%.”
No, it’s not. The additional flux of anthropogenic CO2 is 3% per year. That’s not at all the same thing.
Think of an account paying 3% interest. After 1 year, the proportion of interest to capital in the account is close to 3%. After 10 years, the additional flux of interest to capital is still 3%, but is the proportion of interest to capital in the account still 3%?
No. Absolutely not.

Ben Lawson,
Maybe this will help you out.
The EdGCM Project develops and distributes a research-quality global climate model (GCM)
http://edgcm.columbia.edu/
Obviously you can’t model a physical process which you can’t describe mathematically. Have you ever looked at a GCM to see how they work? Each physical process is broken down into a mathematical model of it’s behaviour, based on physics. Another fundamental rule is that magic is not permitted in modeling.
Perhaps someone needs to publish the fundamental rules of common sense.

Roads (08:19:26)
If CO2 were falling consistently over time, we might predict a new ice age in a few tens of thousands of years. But on the timescale we are considering, it isn’t — quite the converse is currently true, as above — and so we most certainly can’t.:
Again, look at this plot: http://en.wikipedia.org/wiki/File:Vostok-ice-core-petit.png
CO2 does not change the temperature. The temperatures change CO2 with a lag of 800 years, no matter what Gore told you in that movie.
If CO2 falls bellow 150ppm , most plant life will wilt and disappear, so maybe Gaia let us dig up the coal and burn it so that the CO2 that was trapped there could be released and the green stuff can keep flourishing. Green houses, the real ones, flourish with 1000ppm CO2. The alveoli in our lungs work with something like 8000 ppm, saying something about when lungs evolved: when CO2 was much more abundant. ( unless you do not believe in evolution).
In contrast to this, all estimates of CO2 doubling give a small rise in temperature, except the IPCC scaremongering with fictitious water vapor feebacks, that have been disproved by data. A 1C warmer temperature per century is within the flat top of the warm time we are enjoying before the next ice age, and it will be mostly at night time, so whats the problem with having -3C instead of -4C in winter nighttime?
Nothing will melt because of this small rise in night temperatures more than it has been melting ever since the little ice age..

I see that the confusion between climate and weather is reflected at the NOAA site, where the National Weather Service has a Climate Prediction Center that offers a 6 Day Outlook.
It is repeatedly said that the climate is an average of the weather observations, so, presumably, a climate prediction is an average of weather predictions.
It’s not surprising that climate models are actually weather models.
In my view, climate is not described by an average of the weather but by a generalisation about the weather. It’s the same sort of distinction that eluded the very enthusiastic proponents of Artificial Intelligence and natural language generation.

anna v (08:57:30):
Green houses, the real ones, flourish with 1000ppm CO2. The alveoli in our lungs work with something like 8000 ppm, saying something about when lungs evolved: when CO2 was much more abundant. ( unless you do not believe in evolution).
Dear Anna,
Yes, you’re right; and we blow out 53000 ppmV of CO2 in a single breath.

Computer models tell you the consequences of your premises.
If you can apply them to very well known causal patterns and capacities repeatedly, so that they can be tested again and again against real-world outcomes, you can reach a state where they are accurate tests of real-world outcomes. (In other words they and their constituent elements have been subjected to repeated, controlled, empirical tests.) Engineering models are in that situation.
Climate models, and financial models, are not.

jrshipley,
No one is doing any experiments with the climate.
Power plants and cars exist because people’s livelihoods depend on them. Our ancestors didn’t like freezing in the cold and dark, and didn’t have time for playing mental games about whether or nor Gaia is happy about their decision not to freeze.

Steven. I think that matters are a bit more scientific than “guessing Gaia’s feelings”. Also, I think the alternative to changing the climate is moving into caves. Nevertheless, I understand that your retreat to hyperbole is necessitated by the untenability of your position and that a clever turn of phrase in front of an approving audience can be a source of self esteem. That is, I see why you’d say all that.
However and indeed, a simple notion of “experiment” will suffice to make my point. As has been pointed out, we cannot know with absolute certainty what continuing to increase the amount of CO2 in the atmosphere will mean for sea levels, to focus on one concern. It could be not as bad as the IPCC predicts or as recent research indicating accelerated melt rates may indicate it could be much worse. To do the experiment in this case is just to continue to dump increasing amounts of CO2 in the atmosphere. As curious as I am to find out for-absolute-certain whether [snip] who say sea level will stop rising or the conservative IPCC estimates or the more alarmist predictions are correct, I am not so curious as to risk great harm to my fellow humans.

Roger Sowell:
“Could the results be used to better tell you what the thermal conductivity of the pipe wall is, if it were not possible to meause that thermal conductivity in the real world?”
Actually, I believe the answer to that is yes, but only if one is able to measure the outer wall temperature, that is, the edge of the insulation exposed to the atmosphere. If one is unable to measure that outer wall temperature, the problem becomes indeterminant. There would be too many unknown variables, and not enough equations.”
Sorry, I should have been more clear in the hypothetical. Indirect measurements count – if you are able to calclulate the thermal conductivity using an already-proven equation along with measured values for other system elements, surely that counts as an ability to measure the thermal conductivity of the real-world pipe.

jrshipley (12:44:38) :
. As curious as I am to find out for-absolute-certain whether [snip] who say sea level will stop rising or the conservative IPCC estimates or the more alarmist predictions are correct, I am not so curious as to risk great harm to my fellow humans.
But you are willing on the off chance of IPCC being correct to bring the western economy to its knees, the populations back to the middle ages, ( life expectancy 35yrs) and condemn billions in third world countries to starvation.
An altruist for sure.

Steven, did you calculate a trend from scenario B starting around 1990?
(this sentence shouldn t have been part of the quote)
here is the link again:
http://www.realclimate.org/images/Hansen06_fig2.jpg
1973 is another nice starting point, when looking at the scenario B trend…

anna v (13:17:41) :
Hear, hear! Atta girl. Bullseye. Let him have it with both barrels!

kurt (19:49:39) :
Lots of good points in that comment, and one I want to respond to is the idea of having a theory, and a model for that theory, without corresponding observational data.
The example I have in mind is Einstein’s theory of relativity. Specifically, the portion that holds that time dilates as velocity approaches the speed of light. There was no way we knew of to obtain data to test that, until the Apollo program where spacecraft reached high speeds just before re-entry to Earth’s atmosphere. As I remember reading at the time, NASA placed one of two identical, synchronized, and highly accurate clocks in the spacecraft, with the other on the ground. The difference in time readings after the spacecraft landed was exactly what Einstein’s theory predicted, for the velocities achieved.
I am certainly no expert in theoretical physics, but from my readings I am led to believe that physicists made good use of Einstein’s theory before the time dilation tests in the late 60’s.
Another, that you mentioned, is the Bohr theory of the atom. Chemists did good work with that theory, even though the later theories of shells (s, p, d, and f, if I recall correctly) gave better agreement with experimental data.
The opposite is true, of course, as you explained regarding the helio-centric theory of the solar system.

nakedwoadwarrior (14:40:22) : said
“From what I have read on this blog (and I could be wrong here) it seems to this layman that Watts and his guest writers are attempting to explain away global warming as a bunch of liberal huey.”
You are wrong here-it is not liberal huey we object to but unscientific liberal huey: There are now so many of us living on the planet that we will cause damage to it at some point-so if you can hatch a clever plan to get rid of around 50% of the population there might be a chance to return it to the pristine state you seek. The carbon emissions-which to this day have never been PROVEN to cause the dramatic warming claimed-are the least of our problems.
Best wishes-keep reading and blogging here
Tonyb

“…but I cannot believe that our destructive habits will have no effect upon our Blessed Planet.”
I agree that the planet is blessed, but who has it been blessed by? I believe that the planet has been blessed by the appearance of man. Just as we are blessed to have this home. Not one climate realist wants to harm our planet.
Mother Earth loves CO2. The paltry 400PPM or so that exists now is a meager amount for a biosphere that thrives on 1,000PPM and more. Open the floodgates of CO2 and watch our planet return to all her green glory!
Don’t let the politicians take us into a backwards dying earth. Move forward.
“Selfishness is the bedrock on which all moral behavior starts and it can be immoral only when it conflicts with a higher moral imperative. An animal so poor in spirit that he won’t even fight on his own behalf is already an evolutionary dead end; the best he can do for his breed is to crawl off and die, and not pass on his defective genes.”-Robert A. Heinlein

This thread is titled ‘If You Can’t Explain It, You Can’t Model It’, so I am surprised that nobody in the discussion has raised an issue I have repeatedly stated; viz. the lack of evidence for the basic assumption used in the climate models.
The climate models assume that change to climate is driven by change to radiative forcing. And it is very important to recognise that this assumption has not been demonstrated to be correct. Indeed, it is quite possible that there is no force or process causing climate to vary. I again explain this as follows.
The climate system is seeking an equilibrium that it never achieves. The Earth obtains radiant energy from the Sun and radiates that energy back to space. The energy input to the system (from the Sun) may be constant (although some doubt that), but the rotation of the Earth and its orbit around the Sun ensure that the energy input/output is never in perfect equilbrium.
The climate system is an intermediary in the process of returning (most of) the energy to space (some energy is radiated from the Earth’s surface back to space). And the Northern and Southern hemispheres have different coverage by oceans. Therefore, as the year progresses the modulation of the energy input/output of the system varies. Hence, the system is always seeking equilibrium but never achieves it.
Such a varying system could be expected to exhibit oscillatory behaviour. And, importantly, the length of the oscillations could be harmonic effects which, therefore, have periodicity of several years. Of course, such harmonic oscillation would be a process that – at least in principle – is capable of evaluation.
However, there may be no process because the climate is a chaotic system. Therefore, the observed oscillations (ENSO, NAO, etc.) could be observation of the system seeking its chaotic attractor(s) in response to its seeking equilibrium in a changing situation.
Very, importantly, there is an apparent ~900 year oscillation that caused the Roman Warm Period (RWP), then the Dark Age Cool Period (DACP), then the Medieval Warm Period (MWP), then the Little Ice Age (LIA), and the present warm period (PWP). All the observed rise of global temperature in the twentieth century could be recovery from the LIA that is similar to the recovery from the DACP to the MWP. And the ~900 year oscillation could be the chaotic climate system seeking its attractor(s). If so, then all global climate models and ‘attribution studies’( utilized by James Hansen, IPCC, CCSP and etc.) are based on the false premise that there is a force or process causing climate to change when no such force or process exists.
But the assumption that climate change is driven by radiative forcing may be correct. If so, then it is still extremely improbable that – within the foreseeable future – the climate models could be developed to a state whereby they could provide reliable predictions. This is because the climate system is extremely complex. Indeed, the climate system is more complex than the human brain (the climate system has more interacting components – e.g. biological organisms – than the human brain has interacting components – e.g. neurones), and nobody claims to be able to construct a reliable predictive model of the human brain. It is pure hubris to assume that the climate models are sufficient emulations for them to be used as reliable predictors of future climate when they have no demonstrated forecasting skill.
Richard

Also, I apologise for the poor spelling. I type quickly and often forget to proof read.

The only model I believe is Heidi Klumm when she says she’s a German woman.

sod,
The model can show anything you want if you use irrelevant input data. Your argument makes no sense, because the assumptions for scenario B are not based on what has actually happened to atmospheric CO2. Plug the right numbers in and you can get an ice age if you like.
With current CO2 levels, Hansen’s model shows nearly 1C of warming since 1990. (That is what scenario A is.) Even irrelevant scenario B shows nearly 1C warming over the last decade since 1998.
http://www.realclimate.org/images/Hansen06_fig2.jpg
There is a reason why Hansen keeps forecasting the hottest year ever nearly every year. It is not because he expects cooling.

nakedwoadwarrior (14:40:22)
Either way one looks at the issue, the carbon emissions we pump into our atmosphere, along with the pollution from chemical plants, over-fishing of the oceans and deforestation of old growth forests cannot be beneficial to our quality of life or the balance of the ecosystem.
I admire that this blog is seeking to present the other side of the debate, but I cannot believe that our destructive habits will have no effect upon our Blessed Planet.
First, it is great that you are attempting to look at both sides of “the issue”. But what, exactly do you think is the issue? Because it appears to me you have allowed yourself to be hornswaggled by the Alarmist side into believing that we Climate Realists do not care about the other issues you mention, such as pollution, deforestation, over fishing, etc. That is a complete lie, and one of only many fibs they tell.
It is all a big ruse, in an effort to steer your attention away from the ACTUAL issue, which is whether or not C02, and specifically man’s contribution to C02 is driving, or indeed has ever driven climate change, and if so, to what extent? The answer, you will find, is that C02 on the whole has only a minor effect on climate, and man’s contribution of C02 has even less effect. Its biggest effect, in fact is the extremely beneficial one of increased plant growth.
The political stuff is basically a sideshow, yet important because of the harm already being caused, and the ENORMOUS HARM which will be perpetrated on already-weakened economies FOR NO REASON. This is not a Liberal vs Conservative issue, indeed many of us come from Liberal backgrounds, and only investigated because we were curious, and interested in the science. I urge you to do the same. For starters, if you haven’t already, check out Lucy Skywalker’s site, which explains things in laymen’s terms, and with some further good sites linked.

sod,
It should be clear to you by now that Hansen’s scenarios B and C were based on lower CO2. We have temperatures now that are dipping below both of those scenarios but CO2 is much higher.
Scenario A was based on CO2 concentrations similar to what we observe yet his temperature predictions are far too high.
His models are too sensitive to CO2 in other words and do not take into account nature variables that bear strong influence on the climate.

Since there appears to be a bit of down-time in the urgent exchange of cutting-edge science information, I thought a follow-up report about the little purple birds was in order. After the sad report of the freezing death of numerous little purple birds (LPBs) in a blizzard while heading toward Milwaukee, localities in SW Missouri have reported “scads of them” left over. Indeed, the Conservation Status of this species is (IUCN 3.1) Least Concern, or, for those unfamiliar with this scale, three whole levels above American taxpayers.
Jubilant carwash owners have taken to leaving bowls of highly colored berries for the birds to eat, thus preserving this species, and maximizing carwash profits. LBPs have been also called purple finches, the state bird of New Hampshire. Shortly after being named the NH state bird, the birds’ numbers plummeted, causing alarmist birders to blame the less flamboyant and harder-working House Finch of competitive endangerment. This was accompanied by a mysterious change in the coloration of the LPB females’ plumage toward distinctly greenish hues. Traditionalist birders noted that as the females became more green, they became shriller and much more irritable, thus preventing successful mating. Gender confused males, stumped by the color changes, have been known to wander helplessly in urban areas, voicing their mournful cry “Baaar-ney Fraaank!”
Knowledgeable zoologists have assured the anxious populace that the LPBs are successfully migrating toward Milwaukee in time for St Patrick’s Day, and should return to Missouri and the safety of their Bible Belt winter habitat very soon, “to sober up.” Another global warming crisis has been narrowly averted.

Hey, WoadWarrior!
I’m glad you found us, too. Don’t be concerned about not having the same decision-making information as some others here. It will come by osmosis, just reading here. The bottom line is, doubt everything Authority tells you until you can verify it. Pretty simple, really. So, welcome.
One more thing, nakedwoadwarrior. When one of your crazy buddies tries to talk you into a Mel-Gibson-total-blue-body-paint-outfit for Halloween, smack him in the head. Woad is quite astringent. It shrivels things, nakedwoadwarrior. Things you don’t want shriveled. Words to the wise.
Regards, Henry Phipps, MD

Isn’t Huey one of Donald Duck’s nephews?

Given the seven year drop in temperatures, I take it that you are predicting a rapid rise over the next year or two to get back on the scenario A curve?
For new readers, and ‘dealing with reality’ in 1988 Dr Hansen testified to Congress on global warming and as part of the presentation submitted projections of the change in global temperatures from an early version of the NASA climate model under three scenarios, A,B,C, which can be simplified to ‘High’, Medium’ and ‘Low’ [This is a gross simplification – see the original paper for details]. In practice the temperature projections under Scenario B has proven to be extraordinarily accurate – the difference in trends between the projected and the actual trend is actually less than the observational uncertainty, or to put it another way, a ‘perfect’ model would not have done better.
Now in some quarters this evidence of the predictive skill of a climate model has not gone down well, and there have been some attempts to rewrite history, notably by Michael Crichton and also over at Climate Audit, to the effect that Hansen actually believed Scenario A was most likely, or Mr Goddard’s claim that A most accurately tracks the actual forcings. Fortunately we have Hansen’s testimony …
These scenarios are designed to yield sensitivity experiments for a broad range of future greenhouse forcings. Scenario A, since it is exponential, must eventually be on the high side of reality in view of finite resource constraints and environmental concerns even though the growth of emissions in scenario A (~1.5%/yr) is less than the rate typical of the past century (~4%/yr). Scenario C is a more drastic curtailment of emissions than has generally been imagined. It represents elimination of chlorofluorocarbon (CFC) emissions by 2000, and reduction of CO2 and other trace gas emissions to a level such that the annual growth rates are zero (i.e. the sources just balance the sinks by the year 2000. Scenario B is perhaps the most plausible of the three.
Pat Micheals also testified to Congress and in doing so simply erased scenarios B and C, misrepresenting Hansen as an exaggerator. Hansen was not impressed and responded
One of the skeptics, Pat Michaels, has taken the graph from our 1988 paper with simulated global temperatures for scenarios A, B and C, erased the results for scenarios B and C, and shown only the curve for scenario A in public presentations, pretending that it was my prediction for climate change. Is this treading close to scientific fraud?
I know my answer to that particular question. Now, NASA have published estimated radiative forcings up until 2003 and comparing these to the scenarios show that Scenario B was easily the closest match to reality, tracking about 10% higher than observed – while A was 25% higher and C about 25% lower. CO2 has increased slightly faster than in scenario B, but this is offset by a reduction in CFCs thanks to the Montreal Protocols and a plateauing of methane concentrations, for reasons largely unknown.
So, to answer the question, no I am not expecting a reversion to Scenario A anytime soon.
Footnotes: You can download the scenario and forcing data from this page.
The 1988 projections are probably reaching the end of their useful lifetime – a key parameter, climate sensitivity, was set to a value about a third higher than our current best estimate. Over the first few decades this has little impact, but over time will have the effect of causing the model to overestimate temperatures, if the modern value is more accurate. Seven year and longer flat or cooling trends are not unusual in Scenario B, still the planet warms.

John Philips,
Nice long-winded attempt at at obfuscation.
You wrote : Scenario A, since it is exponential, must eventually be on the high side of reality
To date, Scenario A is on the low side of CO2 emissions, as Hansen et al constantly remind us. CO2 has risen faster than Scenario A, and temperatures have risen much slower. The fact that 30 years ago he considered scenario B CO2 to be the most plausible is irrelevant, because atmospheric CO2 has risen much faster than he expected and his prediction was incorrect.
Alarmists can’t have it both ways – claiming that lower scenarios are valid while simultaneously forecasting a 6+C rise in temperatures and “global warming much worse than predicted.” That is exactly the marketing scam which people in Copenhagen are trying to pull off.
Despite widespread concern over global warming, humans are adding carbon to the atmosphere even faster than in the 1990s, researchers warned Saturday.
http://www.huffingtonpost.com/2009/02/14/global-warming-seen-worse_n_167002.html

‘Highly divergent’ Really?

That report found emissions rose by 1.1% per annum during the 1990s rising to 3% this decade, Hansen’s scenario A used a 1.5% per annum increment, so taking into account the ‘compound interest’ effect, overall scenario A is still way higher than observed. Singling out CO2 for a moment, scenario A projected a concentration in 2008 of 464ppm, the actual was 386, so for this GHG scenario A is a 20% overestimate.
So what exactly is the origin of this idea:
To date, Scenario A is on the low side of CO2 emissions, as Hansen et al constantly remind us. CO2 has risen faster than Scenario A, and temperatures have risen much slower. ?
Bill – I assume you aware that the GISS and scenario anomalies use different baselines? It makes a slight difference, also rather then using a single (La Nina) year for your comparison, try looking at the trends