This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.
Objection:
Why should we trust a bunch of contrived computer models that haven't ever had a prediction confirmed ? Talk to me in 100 years.
Answer:
Of course, given the absence of a few duplicate planets and some really large time machines, how can we hope to test a 100 year temperature projection today? Well, we can't, but does this mean that the models can not be validated without waiting 100 years? I don't thinks so.
The climate is a very complex system and our observations of it are by no means complete, even insofar as what is going on today. This is a shortcoming we need to work hard to correct, but it is also an opportunity for validating model predictions. See what the models say some measurement we have never taken should be, then go take it and compare. But before getting into that, there are actually some global temperature predictions that have indeed been validated. We can start with one of the pioneers in climate science. Over 100 years ago, in 1896 Svante Arrhenius predicted that human emmisions of CO2 would warm the climate. He used a much simpler model than current Ocean Atmosphere Coupled Global Climate models that run on super computers, of course, and he actually overestimated the climate's sensitivity to CO2 by a factor of 2. At the same time, he hugely underestimated the degree of warming, thinking CO2 would rise very slowly (how could he have ever predicted the emissions that the future held!) but this is still a pretty impressive very early success.
Running the clock forward, in 1988, James Hansen of NASA GISS fame predicted that the temperature would climb over the next 12 years, with a possible brief episode of cooling in the event of a large volcanic eruption. He made this prediction in a landmark paper and before a Senate hearing, which marked the official "coming out" to the general public of the dangers of Anthropogenic Global Warming. 12 years later, he was proven remarkably correct, requiring an adjustment only for the timing difference between the simulated future volcanic eruption and the actual eruption of Mount Pinatubo.
And let's face it, every year that goes by with an ever increasing global mean temperature trend is one more year of success for the climate models that tell us this will continue to happen until CO2 concentrations stop rising. As well, the predicted acceleration of the rise is also apparent, though to be fair decades will need to pass before confirmation of this is unarguable.
But putting global surface temperatures aside, there are some other significant predictions of enhanced greenhouse gas warming that have been made and confirmed:
- the warming at the surface should be accompanied by cooling of the stratosphere and this has indeed been observed
- as well as surface temperatures warming, models have long predicted warming of the lower, mid and upper troposphere even while satellite readings seemed to disagree. But it turns out the satellite analysis was full of errors and on correction, this warming has been observed
- models expect warming of ocean surface waters as is now observed
- models predict an energy imbalance between incoming sunlight and outgoing infrared radiation. This has been detected
- models predict sharp and short lived cooling of a few tenths of a degree in the event of large volcanic eruptions and Mount Pinatubo confirmed this.
- models predict an amplification of warming trends in the Arctic region and this is happening
And, to get back to global temperatures where we started, models predict continuing and accelerating warming of the surface and so far they are correct. It is only the long term predictions that come with severe consequences that needs the passage of time to prove or disprove them, but frankly we don't have that time at our disposal, action is required in the very near term. We must take the many successes we have already seen as the strong validation that it is.
But if we seek even more confidence, there is another way to test a model's "predictive" power over a long time period and that is called hindcasting. By starting the model at some time in the past, say the turn of the 20th century, and running it forward from that point, all the while feeding it the data about how GHG and aerosol and solar and volcanic and albedo forcing all did play out according to observation, we can directly compare modelled behaviour with actual observations. This of course has been done many times. Have a look at this page and judge for yourself how they did. Would a prediction of temperature for year 2000 made in 1900 have been validated? Would politicians in 1900 have been wise to heed the warnings of science had science been able to do this at that time? Clearly, yes.
This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.
"The Models are Unproven" was first published here, where you can still find the original comment thread. This updated version is also posted on the Grist website, where additional comments can be found, though the author, Coby Beck, does not monitor or respond there.
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Having had a look at the GRIDA page, I am stunned that anybody would consider it a vindication of any hypothesis (except perhaps that the parameters were estimated with the same data as was fed to the model).
Think of it like this: you use a set of exogenous data to estimate the parameters in a dynamic model, and you then plot the estimated values of the endogenous variables. That is all that's been done in that chart.
So if, in other words, the model is a good fit AND the exogenous variables fed into forecasts are EXACTLY WHAT ACTUALLY HAPPENS, the future is likely to look like the model forecast.
How many exogenous variables are there in a climate model and what is their joint distribution? How are they forecast?
I can make a dynamic macro-econometric model tell me anything I want it to - without deviating any of the parameters from plausible values, and using absolutely cast-iron numbers for exogenous variables: if you know the model, you know what things to tweak to give a specific set of answers. And if you want funding, you provide the answers the client wants. If your client is the government, that goes double.
I like your site - it is a very handy resource that shows that there is massive hand-waving and appeal to authority underlying virtually all arguments which 'counter' the questions raised by 'denialists' (did the ADL advise you on how to smear?).
Cheers
GT
Posted by: Geoffrey Transom | December 9, 2008 6:36 PM
"And if you want funding, you provide the answers the client wants. If your client is the government, that goes double."
Right, the US gov't wants there to be global warming. That's why they suppress reports and muzzle their scientists.
"except perhaps that the parameters were estimated with the same data as was fed to the model"
What parameters are you talking about?
Posted by: coby | December 9, 2008 9:20 PM
the global climate models encapsulate our current understanding of atmospheric dynamics. of course the output is based on the input, what else would be expected??? the denialists attack the models by focusing on the uncertaintities due to gaps in our knowledge. they do not, however, attack the underlying scientific bases that form the foundation of the global climate models. their shallow attacks do nothing to counter the two overlying issues: 1) the earth is warming and 2) greenhouse gas emissions are a principal cause.
Posted by: Larry Wilson | December 21, 2008 3:33 PM
Lets take a closer look shall we Coby,
Here are a couple of model predictions that you forgot, Arctic and Antarctic sea ice is at record levels (link needs to be updated).
When sats showed no warming in defiance of the models you simply invalidated near 30 years of data WTF!!!!
But hey if you can predict a volcanoe eruption then who am i to judge.
But enough of this frivolity, lets get down to the real issue.
Firstly if we can prove the IPCC predictions of C02 are over cooked then nothing else matters so lets start there shall we.
The IPCC report of 2000 guessed (using some hidden exponential method)the levels of C02 in the atmoshpere in 2100 would be 836 ppmv with an upper and lower level of 1040 and 720 respectively.
However since Jan 2001 C02 has increased at near linear levels of 200ppmv/century and as usual after seven years the IPCC guesstimate is completely wrong so much so that real world data is way below IPCC projections, so it is safe to say that by 2100 levels of C02 will be around 580ppmv.
Then there is the question of sensitivty,
So now lets apply the formula to these figures and for those math minded of us the formula is:Delta Ts=c1n(C/Co)
Using the IPCC guess of 836ppmv this equates to a rise of 3.6c by 2100 , using the figure of 580ppmv it is only 1.9c.
Upon reading the IPCC reports here is my evaluation of the facts or lack of them to be found:
Were labs experiments conducted?, we are not told
By what method?, we are not told
What steps were taken to replicate the original experiments?, We are not told
What are the methods by which each of the 3 key variables whose product is final climate sensitivity are evaluated? again we are not told.
How did the IPCC evaluate these methods theoretically or evaluated them empirically? We are not told
This is after all the central question to the entire debate and yet the IPCC offers no evidence of how it has come to this conclusion. How does one evaluate the magnitude of the imagined effect of changes in C02 levels on temperature.
For instance the 2001 report says a typical value of the final climate sensitivity parameter is Lambda= 0.5 yet the central estimate of Lambda implicit in the 2007 report is nearly double this value, and there is no explanation for this discrepency.
You make this correct statement, "The climate is a very complex system and our observations of it are by no means complete, even insofar as what is going on today."
But despite this admission of a lack of knowledge and understanding you make the startling claim that we have the knowledge to accurately predict the future climate. On what grounds? Guesswork?
If we do not have enough knowledge as you put it "even insofar as what is going on today." Then how can we construct a model accurate enough to make such predictions?
Posted by: Crakar14 | January 15, 2009 3:16 PM
Hi Coby,
This will be my last post here, but before i go i would like to say it has been fun and somewhat entertaining. I believe sites like this are very important as it allows people to read the opinions of others so that they can become educated rather than indoctrinated. So good luck with the site, before i go i would like to leave you with a link to a story which i assume you have already read but here it is anyway.
I will not make comment on the story as it says it all (re models)
http://epw.senate.gov/public/index.cfm?FuseAction=Minority.Blogs&ContentRecord_id=1a5e6e32-802a-23ad-40ed-ecd53cd3d320
Cheers
Crakar14
Posted by: Crakar14 | January 27, 2009 8:00 PM
[replies inline]
Some basic points:
(1) If you don't include error bars, I cannot judge how accurate your predictions are. And I contend that if you don't KNOW the error bars, you don't know how accurate your predictions are, either. Example: stated solar radiation imbalance of 0.85 W/m2. No error bars. Is the result consistent with zero? No way to tell. Maybe the error bar is +/-0.01 W/m2. But I seriously doubt you could arrive at an answer with 1.1% uncertainty using the methods of this study. (See (2)). Maybe the uncertainty is +/-1.0 W/m2. No way to tell.
[What are you talking about? There are no measurements presented in this post, it is a very general overview - coby]
(2) You need to make sure your headline and the study match. Example: the solar imbalance story, in which the headline (and your summary) are extremely misleading, to the point of being marginally unethical. A careful reading of the text tells us that the parameter that was measured in the "solar radiation imbalance" study was actually ocean thermal energy content growth over the past decade (i.e. 1995-2005). What was NOT measured over the past decade was the actual solar radiation imbalance (as a quick glance at the nice CG earth might suggest). That is, the reflected and absorbed radiation rates were not the object of the study. And in point of fact the ocean thermal energy content was not even measured -- the sea surface and top layer temperatures were measured by buoys and satellites and these results were extrapolated into the ocean depth by a process not revealed in the article, other than to say it was a form of computer model. So saying "models predict an energy imbalance between incoming sunlight and outgoing infrared radiation. This has been detected..." only annoys a real scientist.
[Granted, that study was about indirect measurements and I did not describe it well. Ironically, the best hope for getting that measurement directly was put on mothballs by the Bush admin. Goggle "Goresat", it is a multi 100 million dollar satellite that is ready for launch and just sitting in storage - coby]
(3) Eyeball fits are not acceptable. You simply cannot choose a model and a dataset and say, "See, they kind of rise and fall the same way." There are any number of ways the eye can be tricked into believing there is agreement when there is in fact significant discrepancy. Example: the IPCC GMST measurements. Tell me what goodness-of-fit test you applied (chi-squared? spectral test?) and what p value you derived. DON'T TELL ME, "judge for yourself how they did." This is amateur hour. If I were your referee, I would kick your ass.
[no threats of violence please. For the statistical details please refer to the cited studies. If you can be more specific about which studies you are concerned about, I might have a link handy - coby]
(4) Averaging (or worse, bracketing) several runs to get something that eyeball-agrees with your bias is unacceptable. Example: IPCC study. Why did they show a band of four runs? What does a single run look like? What p value resulted from each of the four runs? Did any of the four runs agree with the historic record, according to an agreed pre-test alpha? What would a band of twenty runs look like? Again, this is the kind of thing first-year grad students get whipped over -- why is this showing up in "authoritative" publications?
[Again, not clear what you are referring to. "IPCC study" could mean any of dozens if not hundreds. But (if this is what you are talking about) the reason multiple runs of GCM's are averaged together is because of the large natural variability in the system. A single run, like the single realization of climate trajectory that is the observed planet earth, contains a lot of randomness. Combining many runs simply gets you a "most likely" averaging. - coby]
(5) Read the abstract before concluding it supports your assertion. Example: 20th century SST trends. "Recent theoretical studies have predicted such a pattern as a response of the coupled ocean-atmosphere system to an exogenous heating of the tropical atmosphere. This pattern, however, is not reproduced by the complex ocean-atmosphere circulation models currently used to simulate the climatic response to increased greenhouse gases." Apparently it is not obvious to you that this study suggests that the models are NOT currently capable of retrodicting SSTs.
[I don't see a problem with this, it supports the general conclusions. Don't forget that as the saying goes, "all models are wrong, but some are useful". So the generation of models this study looked at is not useful for analyzing the PDO and other ocean dynamics, but it is useful for total heat content changes on decadal scales. - coby]
BTW the ghcc link is 404.
[Thanks, I'll try to fix that - coby]
Unlike you, Coby, I'm actually a scientist. So I'm a professional skeptic. Trying to talk down to me (like calling me a "denialist") when you don't know the first thing about scientific discourse only pisses me off. I don't care if you've been blogging about climate change for two years. I'm sorry if I sound self-important -- that's not my intent at all. I came here to learn something about the state of climate modeling. And I'm leaving disappointed.
[I have never encountered bbbeard before, so have never called you personally a denialist. If you want to learn the details of the science, I recommend RealClimate for current issues but you can not do better that starting with the IPCC report and following up with the cited studies, this is really not the place for a technical education, nor was it ever intended to be.
As for your self important tone, I accept your apology, but maybe you can work on that? Thanks for the comment.
- coby]
BBB
Posted by: bbbeard | February 24, 2009 11:09 PM
Hey Dr. Science,
No one really believes the only thing standing between you and a new Prius is a few error bars on a climate modeling chart. I've seen your right wing blog, and you demonstrate classic angry AGW denier symptoms...like rants against government health care and economic stimulus. Your denier agenda may be couched in technical complaints, but your political agenda is loud and clear.
Leaving disappointed Doc? I doubt it. You dropped by for some quick venting, so mission accomplished. No reason to be disappointed. Maybe if you head over to realclimate the real climate scientists will play this fun game with you... but I doubt it.
Posted by: mikatollah | February 25, 2009 6:28 AM
Mikatollah:
So... because I know something about economics, and criticize bad economic decisions... that invalidates my scientific criticism... or something. Drop the label-maker before you hurt something -- like your credibility.
Because I'm a scientist who is angry about the politicization of science, of which this blog entry is an example... my comments about the politicization of science must be demonized. Gee, because I'm "right-wing", I guess that means sloppy science is "left-wing".
I have a suggestion -- why don't you take a critical look at how climate change science is being done, instead of just trying to crib talking points. Science is about skepticism, not agendas.
BBB
Posted by: bbbeard | February 25, 2009 7:00 AM
Come on Doc, admit it... you are still angry about the election and you are scared to death of the climate legislation that will be coming out of the senate this summer.
You aren't angry about the politicization of science, you are angry because it is about to stop. The Republican war on science (good book by the way) has no more soldiers since the voters turned you out, so you think you can change minds here?
Unlikely...
Posted by: mikatollah | February 25, 2009 7:49 AM
BBB: please see my reply inline.
Posted by: coby | February 25, 2009 9:23 AM
Hi Coby,
Okay, I'm calmer now after some spicy beef salad and eggrolls at Surin Madison. ;-)
Most of my comments were directed at links in your post, not at what you wrote in your text.
So, e.g. in the article you linked "Scientists Confirm Earth's Energy is Out Of Balance" the following sentence appears: "The current imbalance is 0.85 watts per meter squared (W/m2) and will cause an additional warming of 0.6 degrees Celsius (1 degree Fahrenheit) by the end of this century." My complaint about such pronouncements is that they are typically provided without an uncertainty estimate. It may be that the original technical article has an error bar, but my experience over the last ten years of chasing down such climatology articles is that most don't (many of the IPCC figures do, however!). If you have access to the original article could you please look up the uncertainty? What were the primary contributors to the uncertainty?
The IPCC GMST article I referred to was one of the ones you linked, http://www.grida.no/climate/ipcc_tar/wg1/figspm-4.htm. IIRC (the link won't open at the moment) the authors ran a total of 4 trajectories and provided a grey band that represented the spread of the trajectories. As I pointed out, providing a line that crosses a band multiple times is not a good way to capture goodness-of-fit.
My complaint about the SST abstract (http://www.sciencemag.org/cgi/content/abstract/275/5302/957) was that it contradicted the assertion that GCMs have been validated for SSTs. Your text actually only claimed "models", not GCMs in particular. But this begs the question, doesn't it? Why do you trust GCMs to set policy when they don't agree with observations?
GCMs, for me, anyway, are at the root of my skepticism about global warming. I have pretty wideranging experience with numerical models, including everything from lattice gauge theory to computational fluid, thermal, and structural dynamics. Validation is absolutely crucial, and you have to be absolutely painstaking. The minimal test for a GCM, it seems to me, is that it must successfully retrodict a significant period of recent historical global climatology using unfitted historical inputs. And "successfully" in this case means that it must pass a standard goodness-of-fit test chosen a priori, with a significance level chosen a priori. (Eyeball fits do not meet this criterion.) I would not design an airplane with an unvalidated code, much less commit trillions of dollars of GDP to climate amelioration. (Of course, a trillion dollars ain't what it used to be.)
Even so, there are lots of ways system models can produce divergent output that doesn't correspond to real world behavior. Eliminating spurious phase transitions and capturing actual divergences is far from trivial. It's a real problem pushing models into unknown territory.
Best regards
BBB
Posted by: bbbeard | February 25, 2009 8:20 PM
This is an interesting story the title is "If you cant explain it, you cant model it"
http://wattsupwiththat.com/2009/03/15/if-you-cant-explain-it-you-cant-model-it/#more-6220
Now i have not read all 172 comments and do not subscribe to them so if you are going to pelt me with peanuts from the gallery please base your comments on the article alone.
Cheers
Crakar
Posted by: Crakar14 | March 16, 2009 5:06 PM
That quote from one of the sources referenced by your linked article really tells the whole story. Climate models model climate. Climate is a 30 year average of weather conditions. If you ask a climate model what the temperature will do over the next 10, or 15 years, the answer will be unreliable. As you get closer and closer to lengths of time in the 30 year range, your answer gets more and more reliable.
The biggest reason to place confidence in the state of the art GCM's is their ability to hindcast the 20th century.
Posted by: coby | March 16, 2009 7:53 PM
Hi there Coby, how long to go before your new arrival? Hope everything is going well.
In regards to your post the quote makes sense, is it relavent? probably not, why would you ask a model to do something outside of its abilities?
In regards to hindcasting i am not aware of any with this special ability. Even your statement does not make sense in regards to 30 year, 15 year etc.
How can a 30 year prediction be more accurate than a 10 year one. Small errors will become a lot bigger in 30 years than in ten. But i suppose the best thing about a 30 year prediction is that half the people you tell will be dead and the other half would have forgotten in that time frame, its called covering ones arse.
Here are some quotes to justify my POV
Thus IPCC lead author for the Working Group 1 science report, Kevin Trenberth, writes
on Nature’s Climate Feedback blog that “The state of the oceans, sea ice, and soil
moisture has no relationship to the observed state at any recent time in any of the IPCC
models. There is neither an El Nino sequence nor any Pacific Decadal Oscillation that
replicates the recent past; yet these are critical modes of variability that affect Pacific
rim countries and beyond”. Accordingly “... there are no (climate) predictions by IPCC
at all. And there never have been”, but instead only ““what if” projections of future
climate that correspond to certain emissions scenarios”.
This view is reinforced by
another WG1 lead author, Jim Renwick, Renwick, responding to an audit which showed
that the climate forecasts issued by New Zealand’s National Institute of Water and
Atmosphere (NIWA) were accurate only 48% of time. In other words, one can do just as
well by tossing a coin. Renwick’s comment was that “Climate prediction is hard, half of
the variability in the climate system is not predictable, so we don’t expect to do
terrifically well”.
A third blow to the credibility of IPCC GCM forecasts was delivered by Armstrong and
Green (2007) in an audit of Chapter 8 in the latest IPCC report. They find that “in
apparent contradiction to claims by some climate experts that the IPCC provides
“projections” and not “forecasts”, the word “forecast” and its derivatives occurred 37
times, and “predict” and its derivatives occur 90 times in the body of Chapter 8”. Having
analyzed the IPCC’s approach in detail, Armstrong and Kesten’s conclusion is that
“because the forecasting processes ..... overlook scientific evidence on forecasting, the
IPCC forecasts of climate change are not scientific”.
I think i have made my point.
Cheers
Posted by: Crakar14 | March 16, 2009 11:55 PM
mikatollah, February 25 2009, above, refers to the politicisation of science.
This is the inevitable consequence of the political funding of science. Given that virtually all climatology is politically funded, we cannot reasonably expect anything but a systemic skewing of such science such so as to favour political action over inaction, by providing a rationale for further expansion of the state, and thus also the power, wealth and status of climatology's political paymasters.
Reinforcing the political bias in today's science, is that grants for science are far more likely to go to those who come with apparent problems to solve, compared to those who say all is well, or at least question the basis for alarm.
It may of course turn out that climate alarmism is objectively rather than merely politically justified, but I cannot but wonder what the prevailing view would be if instead of the alarmist faction getting 99% of the funding, it was instead split 50-50.
Posted by: BFJ Cricklewood | March 17, 2009 7:41 AM
Re: Crakar's references.
Kevin Trenberth's article
http://blogs.nature.com/climatefeedback/2007/06/predictions_of_climate.html
I don't think he's saying here what you think he's saying. Taking quotes out of the context of the post may make your argument seem good superficially, but reading the article gives you a very different sense than what you're trying to imply about it.
Audit of NIWA's data
http://nzclimatescience.net/index.php?option=com_content&
task=view&id=38&Itemid=34
EXTRA EXTRA READ ALL ABOUT IT!! SCIENTISTS CAN'T PREDICT WEATHER! ALSO, WATER IS WET AND ANIMALS NEED TO EAT!
Seriously, he's making a claim about climate prediction, and here NZ Climate Science is grading him based on weather. And EVEN then, the predictions were right (according to NZ Climate Science's methodology, which I have issues with) half the time!!!
Couldn't find your last reference, can you provide a link?
Posted by: Adam | March 17, 2009 10:51 AM
BFJ Cricklewood -
It may of course turn out that climate alarmism is objectively rather than merely politically justified, but I cannot but wonder what the prevailing view would be if instead of the alarmist faction getting 99% of the funding, it was instead split 50-50.
This is an interesting claim. Funding is given to climate scientists, not 'alarmists' or 'skeptics'. And, in fact, climate scientists overwhelmingly come to the conclusion that the earth is warming, and humans are the likely cause. It's not some global conspiracy to levy more taxes so scientists can jet off to the Arctic for Aurora Borealis Gazing Parties. I'm especially confused by the tax claim (not that you're making it, but others are), because it seems governments are bending over backwards to avoid levying carbon taxes.
Posted by: Adam | March 17, 2009 11:04 AM
Crakar, it is hard to respond properly to your long comments, they contain too many assumptions and cover too many topics. I stopped reading the on above at this line:
Perhaps we can focus on this and try to have some points of understanding. This is a common misconception and the problem resides in the difference between weather and climate. For instance, can a 4 month prediction be more accurate than a 4 day one? The answer is yes. Yes, I can predict with a very high degree of confidence that the temperature here in Vancouver will be substantially higher in 4 months, but I can not say the same for four days from now. Weather prediction is about initial conditions and how they will evolve. In weather prediction the further out in time you go the less accuracy you can expect. Climate prediction, like seasons, is about the range of possible states a system can have given some general properties. The initial state does not matter, as time passes averages emerge more clearly. The NH of the earth will be leaning more towards the sun in 4 months so I know it will be warmer, it does not matter if it is 3oC, 5oC or 10oC today.
We are in a period dominated by short term weather phenomena, specifically La ninas, but there is no reason not to expect the average trend to be reestablished. The articel you referenced was casting doubt on climate models because they have failed to predict the current stasis of global temperatures. My quotation was making the point that climate models are not designed to make 10 year predictions, so don't ask them for that.
Can we agree on this? If not, please make a focused counter argument!
Posted by: coby | March 17, 2009 2:46 PM
"...given the absence of a few duplicate planets and some really large time machines, how can we hope to test a 100 year temperature projection today?"
The answer to that is simple. Feed in the past 100 years worth of data into the model and see if it accurately predicts the actual climate we have today. If it doesn't, then it is a pretty good indication that the model leaves something to be desired. None of the models currently being used to predict the future are good enough to predict the past or the present. There is a scientific explanation for that state of affairs: garbage in-garbage out.
Posted by: Tom | March 17, 2009 7:42 PM
Tom, please continue reading to the bottom. Click the last link. The models do a very good job of reconstructing the 20th century.
Posted by: coby | March 17, 2009 10:31 PM
Adam: Funding is given to climate scientists, not 'alarmists' or 'skeptics'.
Maybe in theory. In reality, state-funded employees will tend to favour the state, and thus skew their findings to promote the state. It's not objective science, it's politicised science; science funded by, and therefore primarily serving, the interests of the state. Rather like the tobacco scientists who came up with studies skewed against any cancer link.
And climate scientists overhwhelmingly conclude the same thing, because they're overwhelmingly funded from the same institution in society. No conspiracy is needed to explain anything here, it's just systemic bias. All the so-called peer-reviewing, is from other beneficiaries of the same skewed system.
Yes, governments are indeed balking at the ruinous levels of taxation and regulation being demanded (on top of the already huge financial system 'rescue' measures). But only because they fear for their popularity, not because they don't like the idea.
Posted by: BFJ Cricklewood | March 18, 2009 2:19 AM
BFJ -
I'm not really sure how a government is put at an advantage for promoting global warming if it doesn't exist. What's the motivation of a politician to advocate for dealing with global warming if it's not actually a problem? Levying additional taxes? We've already seen (and you acknowledge) that they go to great lengths to avoid doing that.
It's not objective science, it's politicized science; science funded by, and therefore primarily serving, the interests of the state.
Do you also feel the same way about evolutionary biologists, astronomers, research oncologists, geologists and particle physicists? If not, why not? If so, maybe you will acknowledge that state-funded science can actually produce good results.
Posted by: Adam | March 18, 2009 6:05 AM
Adam:
Modern governments do not "go to great lengths to avoid levying taxes". They do the exact opposite. That there are some taxes they feel they cannot get away with, does not alter the point.
"What's the motivation of a politician to advocate for dealing with global warming if it's not actually a problem?"
It provides an excuse to impose more state control over society. When the state's paid lackeys come up with reasons for expansion of the state, you'd have to be nuts to credit them with objectivity.
Politically-funded science is defiled by politics to the extent the issues it deals with have political ramifications. Climatology clearly ranks high in this respect, the other disciplines you mention perhaps less so.
Posted by: bfj cricklewood | March 18, 2009 9:59 AM
BFJ -
Modern governments do not "go to great lengths to avoid levying taxes". They do the exact opposite. That there are some taxes they feel they cannot get away with, does not alter the point.
I only meant that they have (thus far) avoided levying taxes specifically for dealing with climate change. I certainly didn't mean it as a general observation.
It provides an excuse to impose more state control over society. When the state's paid lackeys come up with reasons for expansion of the state, you'd have to be nuts to credit them with objectivity.
Okay, so, if the government was going to invent something to exert more state control over lives, why would it be something as complex, subtle, and long-term as global warming? There are far more things that are 'immediately' scary than climate change. If you want to scare people into accepting more state-control, you don't threaten them with something where the worst effects happen 50+ years from now.
We've seen the immense difficulty in actually getting climate change legislation passed (mostly, I'm talking about the US, I haven't followed other countries as much), and if government officials are as manipulative, sinister and intelligent as you think they are, I'm sure they would have tried to scare us with something else, if that was their intention. unless, of course, they KNEW I would think that, and therefore are doing it because it seems so difficult to accomplish (this is where paranoid thinking leads you, to these endless layers of conspiracy and double-secret motives and misdirections. But, thankfully, modern governments are not Adrian Veidt).
It really makes no sense for some government cabal to push the Global Warming 'myth' as a way to attain more power.
But, as with everyone else, if you have some specific qualm with the science (other than nebulous conspiracy theories), I'd be happy to discuss them with you.
Posted by: Adam | March 18, 2009 11:09 AM
Here is the link to the article from which i got the quotes;
http://scienceandpublicpolicy.org/sppi_originals/the_myth_of_dangerous_human_caused_climate_change.html
It is a very good article written by one R.M. Carter Ph.D, he touches on several topics one being computer models. He talks about two types of models, one being GCM's (used by the IPCC) which project/predict a warming climate and a second which is considered the more accurate of the two which projects/predicts cooling. However they both suffer from the Kelvin fallacy or in other words if you cant explain it you cant model it. Now i dont expect us to agree on everything he says but i am sure on some topics we will.
To Adam, you can disagree with me when i say the models dont work thats fine, i except that it is only my unqualified view of things, however Messers Trenberth and Renwick have a qualified view you need to accept it. Your argument of "taking out of context" is very weak. Both links you supplied prove that nothing was taken out of context and the harsh reality is that the models DO NOT model climate very well.
Cheers
Posted by: Crakar14 | March 18, 2009 5:49 PM
Hi Coby,
First of all make sure you get the Anti-colic teats for the baby bottles (i am very tired today).
In regards to models and projection/predictions i think i understand what you are trying to say.
We have weather models that give us a reasonably accurate 7 day forecast on the nightly news and we have climate models that project/predict the climate in 30, 50, 100 years? Am i right so far? If so then.........
If you produce a model that lets say predicts among other things a temp rise of 3C by 2039. Now this is a 30 year model so regardless of what happens in the next 29 years my model is still accurate because my model cannot predict El Nino, La Nina, PDO, AMO,IPO and i assume cloud formation etc. If the temp is below 3C the following year because you cannot predict previously mentioned drivers then you are wrong but who cares, you, i and everyone else we knew will be dead or suffering from dementia or just lost interest and forgotten about it.
Here is my view on this logically flawed approach if i produce a model using the same scenario and i cannot account for the climate drivers listed above then what hope have i got of producing an accurate result?
What in heavens name makes you think that a model does need to or cannot be accurate for 10, 15, 20, 25 years but somehow as if by magic it has the IPCC garantee that it is accurate at 30 years? How can this be?
You have two lead authors of the IPCC telling you the IPCC cannot predict climate but yet still here we are debating a moot point.
Cheers
Posted by: Crakar14 | March 18, 2009 8:10 PM
The Science and Public Policy Institute are a couple of right wing political hacks who will say and do anything to deny the science of AGW. They carefully hide the sources of their funding out of fear they will be discredited when people discover their true agenda.
They conduct no climate science and are unqualified to be considered experts on computer modeling. What they are experts at is manipulating opinions of the uninformed.
Wait, I'm being too kind... they are dogfaced liars.
Posted by: mikatollah | March 18, 2009 9:37 PM
Of course they are Mikatollah, anything that opposes your views fits into this catagory.
I notice you made no attend to address the issues of the post, you just sat in the gallery and started throwing peanuts as usual. If you are serious about religion i here the bible is a good read, better than anything the IPCC has produced anyway.
Posted by: Crakar14 | March 18, 2009 10:26 PM
"What in heavens name makes you think that a model does need to or cannot be accurate for 10, 15, 20, 25 years but somehow as if by magic it has the IPCC garantee that it is accurate at 30 years? How can this be?"
There is no magic guarantee, nor is it a sudden switch at 30 years. The more time that passes, the more confidence there is in the prediction, because the less influence natural variability will have.
ENSO, PDO etc are not long term climate drivers, they are weather patterns.
Posted by: coby | March 19, 2009 1:02 AM
Coby is far more patient with deniers than I am Mr. Crakar. Your complaints about climate models have all been expressed before and I see nothing new here to comment on.
Give us one thing that we haven't all heard before...
Posted by: mikatollah | March 19, 2009 6:05 AM
You have two lead authors of the IPCC telling you the IPCC cannot predict climate but yet still here we are debating a moot point.
We've been over this already. You are either misrepresenting their statements that modeling is not a perfect science, or taking their comments out of context (also known as quote-mining, another denialist favorite).
Posted by: Adam | March 19, 2009 10:31 AM
Ok lets call this one a draw,
Although if you are interested we could continue. How about rather than me try to convince you the models are wrong, why dont you try and convince me the models are right.
You could show real world data (sea ice, temp trends etc)that have already been predicted by the models in the past.
Mikatollah,
I had a look at Hotberry, are you Mike? Nice pics.
Cheers
Crakar
Posted by: Crakar14 | March 19, 2009 7:16 PM
Crakar -
It's probably useful to define what exactly a climate model is in this case. This is a useful guide
http://www.realclimate.org/index.php/archives/2008/11/faq-on-climate-models/
http://img507.imageshack.us/img507/7062/ar4fig95lger2.jpg
The ability to hindcast the 20th century (as has been pointed out numerous times on this thread) is probably the
main reason to have some degree of trust in the models.
Coby also has some links in the main post that you can take a look at for model predictions.
Posted by: Adam | March 19, 2009 8:44 PM
Adam: Okay, so, if the government was going to invent something to exert more state control over lives, why would it be something as complex, subtle, and long-term as global warming?
Because complex things can be said to be comprehensible only by (our, state-paid) experts, so don't argue back, Mr Lay Citizen.
For anyone remotely interested in getting to the bottom of this, wilfully blinding oneself to the correlation between the facts that
* 99.9% of climatology is state-funded
* climatology is being used to justify expansion of the state
is just plain madness.
And one need not posit a conscious conspiracy here, one need merely consider how control over funding might translate into systemic control over findings and research agendas.
Posted by: bfj cricklewood | March 20, 2009 6:40 AM
BFJ -
Yeah, all that pretty much sounds like boilerplate tinfoil hat stuff. And if, by some twist of fate, you are correct and its all true, then clearly the government is far smarter than I give it credit for (being able to orchestrate such an elaborate scheme) and I gladly bow before my new Climatological Overlords.
Posted by: Adam | March 20, 2009 10:08 AM
Adam-
As mentioned, you don't need to assume smartness or conspiracy. You just need to be realistic about what effect holding the climatology purse strings would tend to have, particularly as regards conclusions relating to the state's role and legitimacy.
Posted by: bfjcricklewood | March 20, 2009 11:37 PM
http://www.rocketscientistsjournal.com/2009/03/_internal_modeling_mistakes_by.html
Interesting reading, this guy lists 8 reasons why the models dont work. I would be interested in hearing other peoples thoughts on this.
Crakar
Posted by: Crakar14 | April 5, 2009 9:57 PM
Crakar -
Statements like this:
CO2 HAS NO MEASURABLE EFFECT ON CLIMATE
are just so monumentally stupid that I didn't even bother to read the rest of his post.
Posted by: Adam | April 6, 2009 10:17 AM
Just typical of you Adam, anything which contradicts the AGW theory is ignored out of hand. This closed mind mentality of yours is based on what? An untested theory promoted by the IPCC?
I actually feel sorry for you, i cannot imagine what it would be like to go through life not questioning anything that is put in front of you, not having the capacity for free thought. It must be horrible.
Posted by: Crakar14 | April 7, 2009 7:31 PM
Coby,
I have a few problems with the models:
First, the models call for polar amplification.
Polyakov shows that the Arctic warming trend is only slightly higher than the Northern Hemisphere trend. He also shows that the Arctic is cooler now than it has been in the 20th century.
Polyakov et al (2003) The composite temperature record shows that since 1875 the Arctic has warmed by 1.2°C, so that over the entire record the warming trend was 0.094°C decade−1, with stronger spring- and wintertime warming. The Arctic temperature trend for the twentieth century (0.05°C decade−1) was close to the Northern Hemispheric trend (0.06°C decade−1). The oscillatory behavior of Arctic trends results from incomplete sampling of the large-amplitude LFO. For example, the Arctic temperature was higher in the 1930s–40s than in recent decades, and hence a trend calculated for the period 1920 to the present actually shows cooling. Enhancement of computed trends in recent decades can be partially attributed to the current positive LFO phase.
Serreze realized this problem with the climate models and attempted to show that ice loss would actually start the Polar amplification.
Serreze et al (2006) Rises in surface air temperature (SAT) in response to increasing concentrations of greenhouse gases (GHGs) are expected to be amplified in northern high latitudes, with warming most pronounced over the Arctic Ocean owing to the loss of sea ice. Observations document recent warming, but an enhanced Arctic Ocean signal is not readily evident. This disparity, combined with varying model projections of SAT change, and large variability in observed SAT over the 20th century, may lead one to question the concept of Arctic amplification.
Then we look at the Antarctic. Once again studies show that the Antarctic was the warmest in the 1930-1940s. Further, the Antarctic has been cooling for the last 40 years.
So there is currently no polar amplification. The only way to show one is to cherry pick your start date, as was done for the Antarctic to show warming.
Once you address this point I will be glad to talk about the others.
Posted by: Vernon | May 14, 2009 11:00 AM
Coby,
No comments yet?
Posted by: Vernon | May 18, 2009 8:49 AM
Sorry Vernon, to busy to answer properly. But lets see what discussion we can scare up here.
Posted by: coby | May 18, 2009 12:13 PM
".. in 1988, James Hansen of NASA GISS fame predicted that the temperature would climb over the next 12 years, with a possible brief episode of cooling in the event of a large volcanic eruption."
Yes but his prediction was remarkably WRONG by 300%, which is "scenario A". Scenario A was business as usual, which has been the case since then.
" 12 years later, he was proven remarkably correct,.." No he was proved remarkably wrong ... being 300% off is being remarkably wrong.
He later said "and the facts show that the world has warmed up more rapidly than scenario B, which was the main one I used..." Not so Mr Hansen you have backtracked from your original testimony.
And in any case even scenario B has since moved higher than reality and lets see over the next few years.
Posted by: Richard | May 26, 2009 9:52 PM
"another way to test a model's "predictive" power over a long time period and that is called hindcasting"
This statement is complete rubbish. If the models are built to take all available data into account, then feeding them just part of that data as input will inevitably see them spew out results that match. The ONLY valid test for a model is to have it predict now what is going to happen in the future.
Secondly, just having models predict 'warming' is not enough. To be valid, they have to predict a precise (within reason) change that can be measured in degrees per unit time. For example, James Hansen's 1988 models predicted temperature rises orders of magnitude greater than those actually observed.
Posted by: James | July 1, 2009 7:37 AM
Posted by: dhogaza | July 1, 2009 7:47 AM
As dhogaza says, simply false, James.
http://scienceblogs.com/illconsidered/2006/04/hansen-has-been-wrong-before.php
Posted by: coby | July 1, 2009 8:53 AM
James -
This statement is complete rubbish. If the models are built to take all available data into account, then feeding them just part of that data as input will inevitably see them spew out results that match.
It's always amazing to me how casually denialist trolls will accuse scientists of severe, serious fraud without a shred of evidence other than the results don't show what they [denialists] want. It's great that you're exercising your first Amendment rights, James, but it'd be nice if you used them for something other than libel.
The ONLY valid test for a model is to have it predict now what is going to happen in the future.
Considering we don't know what the inputs should be (volcanic eruptions, major storms, emissions, etc, etc) then, no, this isn't a good way to validate a model. Hindcasting, where we know both the inputs and the outputs, provides an excellent set of data to test models with. The fact that you are unable to accept the results, frankly, says more about you than it does about the models (and I certainly don't mean that it says something positive, just to be clear).
Posted by: Adam | July 1, 2009 9:30 AM
I don’t know why everyone still praises Hansen’s model. To me it is a very poor model. Considering that he was able to “predict” effects of Pinatubo as described, I find it almost appalling that no indication of El Nino (1998) peaking is represented in his model outputs. A linear extrapolation of past 20 years of data would yield you much the same result well within noise and instrumental error to be as good of a match (but not a good model)
Posted by: ThomasC | July 14, 2009 3:43 PM
ThomsC, Hansen's model did a pretty good job of predicting the temperature rise. Note that the models feature forcings. That is why volcanoes are included since the sulphate aerosols emitted affect the forcing by reflecting SW radiation and thus preventing it from reaching the earth, being absorbed by the earth and being re-emitted as LW radiation (heat).
The El Nino, La Nina cycles do not involve forcing but are effects caused by rearrangement of the heat. During an El Nino the surface of the ocean is heated and thus heats the air. During this heating phase evaporation occurs and the water becomes more saline (higher density). A point is eventually reached where the surface water, though warmer than the water beneath it, sinks and removes ocean heat content from the surface to the abyssal depths of the ocean.
Cold abyssal water is displaced and makes its way to the surface where it cools the air. Note that during these cycles there is no real change in energy content of the ocean or the air only a rearrangement.
Since the models are based on forcings they cannot predict El Nino events. Hopefully, newer models will be able to include these events once they are better understood and measured.
Scenario A was not 300% wrong as Richard claims, this was a figure which featured in Crichton's work of fiction. Hansen also indicated that he felt that Scenario B was the most likely to be followed in the real world.
It is too bad that so many deniers try and distort the actual data and interpretations of the data that the scientists provide. It is much better to actually read the papers as printed in the scientific literature and discussed by the scientists actually working in the area.
Posted by: Ian Forrester | July 14, 2009 4:30 PM
The model output you've seen is almost undoubtably the averaging of many runs, as this approach better meets the needs of researchers trying to answer questions like "what's the climate sensitivity to a doubling of CO2?". Not "will the first El Niño of the 22nd century occur in 2110 or 2115?". The averaged output is typically what is plotted and presented in reports like those from the IPCC.
Aerodynamic models have exactly the same problem - yet airplanes fly.
Modeling the physics that goes on inside a hydrogen bomb has exactly the same problem - yet the bombs blow up.
Posted by: dhogaza | July 14, 2009 5:07 PM
Please don't be frightened away by the title of this video?
Please watch it right through?
To quote the youtube poster:
"David Evans worked for the Aust Greenhouse office as a modeller and established the worlds best method of carbon accounting. He also started to realise CO2 is not the cause of dangerous global warming. Here he explains why... "
http://www.youtube.com/watch?v=rTUDWy6T050&feature=channel
Posted by: Michael | August 16, 2009 7:05 PM
I doubt they watched it Michael, Evans is no doubt a liar and a nutjob like Monckton.
By the way i have just completed writing a computer program which predicts the winners of the AFL grand final and the super bowl 100 years (2109) from now, and the winners are.....drum roll....Geelong and the Seahawks.
It will be difficult to prove me wrong as 99.99% of the population will not be alive to see my predictions come true and the remaining 0.01% will not be aware of the milestone reached due to senility.
Now this program takes into account millions of different ever changing parameters of things that we dont fully understand and no i will not give you access to the source code.
However i challenge anyone to prove me wrong, and no calling me a liar and a nutjob does not prove me wrong OK.
So get to it then.
Cheers
Crakar
Posted by: crakar14 | September 28, 2009 10:53 PM
David Evans is an engineer, not a scientist, and has no credentials in climate science.
He famously claims to be a "rocket scientist" but has never worked in the aerospace industry, or with rockets, space program, etc.
When called on it, he gave this explanation:
That's laughable.
So why should I believe what an electrical engineer says about the physics of CO2 rather than trust what physicists have learned over the last 150 years?
Should I also accept his views on evolution? Economics?
Rocket science?
Posted by: dhogaza | September 29, 2009 9:35 AM
You can find the source code to GISS Model E linked to from this page. Why can't I see the source to yours? What's your point?
I find it, and the high-level documentation, very useful when countering claims that "the models don't include clouds", etc.
Some things are easier to predict than others. Your snarky sports prediction is an example of in essence weather prediction, and no one claims that models can do so.
On the other hand, I can predict with certainty that as long as the business structure of american major league baseball remains the same, that as of 2100 the New York Yankees will still have won more championships than any other team.
This is more similar to climate projections than your snarky one. Climate projections are about long term trends (as is my long-term prediction about the Yankees), not about individual weather events in a particular year. The projections are based on axiomatic preconditions (in my case, the business structure of MLB doesn't change; in the case of climate models, that CO2 emissions track a certain projection, no asteroid hits the earth, sun doesn't supernova, etc).
If you don't think models are useful - don't fly. Modern airliner design is heavily model-driven.
That's why they're so much safer than the old British Comet or Boeing 707.
Posted by: dhogaza | September 29, 2009 9:44 AM
Dogaza just when you start to show your humorous side you let me down, the only way you could have proven my model to be incorrect was by saying that the seahawks can never win the SB.
Here is what Evans has achieved
http://74.125.153.132/search?q=cache:xe0KzSUKdX8J:sciencespeak.com/DavidEvans.doc+Dr+David+Evans+biography&cd=2&hl=en&ct=clnk&gl=au
Now just to clear up a few misnomers dogaza there is no such thing as a "rocket scientist" per se thats because there are many disciplines that are required to design, build and launch a rocket too much knowledge is required therefore no one man can ever call himself one.
The same goes for "climate scientist" they dont exist for the same reasons. If i have worked on rockets does this make me a rocket scientist? If so i better update my resume.
Now back to my model, if you honestly believe that the bought and paid for scientists of the IPCC dont act in any way other than with honesty and integrity then you are wrong (i dont like to call people liars like you do). Its funny but if you read the Monckton article this would be more clearer to you but alas he is a liar also. Take off your rose colored glasses for once and you will realise that many IPCC scientists do not allow others to view how they arrived at their results.
I am glad you mentioned models that design aircraft for i have a really good example i would like to share with, imagine a company that wants to design a plane that can travel at 4 times the speed of sound, how do they do this?
Well they take thier existing knowledge and a dollop or two of guess work and develope a program to design the plane. Now they know that this design will not be perfect but it will be enough for the scaled down test aircraft to fly. They can then bolt the test aircraft to a rocket and launch it high up into near space and on its return they can take thousands of measurements.
What do you think they will do with this data dogaza? Thats right they adjust the computer model, they use real life data to verify and adjust the model. As opposed to the IPCC which say "the oceans are cooling", "not if we ignore the sat data they aren't", "phew that was a close one".
Posted by: crakar14 | September 29, 2009 8:43 PM
mikatollah: In the months since you posted, the GOP has succeeded in stopping the Democrats' agenda in its tracks. There won't be any climate change legislation in 2009. It's uncertain whether there will even be health care reform legislation in 2009.
Posted by: sinz54 | October 1, 2009 7:53 AM
There won't be any climate change legislation in 2009. - Sinz54
How nice. Just as well the American southwest is going to one of the first to suffer the effects of AGW. Just desserts huh?.
Posted by: Dappled Water | October 1, 2009 11:53 AM
Methinks someone's counting their chickens before they hatch, as the agenda hasn't been brought to a halt. What's been brought to a halt is the stupid notion of "bipartisanship", which we won't get and should stop caring about.
The EPA's drafting rules which will regulate the largest sources of CO2 in the US, and is putting into place new mileage standards for cars and trucks which will also move things in the right direction. The GOP and industry (hey, check out those big companies bailing on the US Chamber of Commerce) will have a choice: support a reasonable climate bill or let Obama and the EPA set the agenda without them.
Health care? A bill's coming out of the Finance Committee soon, and with Ted Kennedy's replacement sworn in, they no longer need Olivia Snowe's vote to break any filibuster effort.
Now, is either bill going to be as strong as progressives would like? No. But they'll both represent a very large step forward from the status quo.
Posted by: dhogaza | October 1, 2009 12:31 PM
I see you left the thread that you closed this one for out to die because it could no be answered and now we are back here.
Shall I post the stuff you could not answer there here?
Posted by: Vernon | October 1, 2009 3:01 PM
And just think, English is this dude's native tongue ...
Posted by: dhogaza | October 1, 2009 5:53 PM
dhogaza said:
I noticed in the thread above that the only person who actually brought up the topic of model validation (bbbeard) was ridiculed for the politics on his blog, and his criticisms weren't actually answered. Your example of model use in aeronautical engineering is a good one. The important thing to understand about why they are so successful is the stringent verification / validation practices that groups like AIAA and ASME promulgate (and the significant amount of effort over the past few decades that's gone into the development of those best practices).
Pretending that model validation in climate science isn't an open research question, or belittling people who point out the gaps, is just advocacy not honest debate.
Posted by: jstults | February 5, 2010 6:30 PM
Let's see, I think a little issue has been over looked here
The FAA requires that flight testing be successfully completed prior to certification. And that testing will be done under the Independent eyes of FAA personnel in real time.
It's called Independent Validation.
Yet Another Naked Strawman ( YANS ) by dhogaza; short, thin, single-straw version.
Posted by: Dan Hughes | February 9, 2010 12:33 PM
What?
Posted by: skip | February 9, 2010 3:47 PM
Yes. Before certification. Not before flight testing (d'oh). When two test pilots are trained on a simulator built in parallel with the airplane, and the plane flies the first time exactly as they were led to expect by their training in that simulator, I think the model underlying the design and implementation of both the airplane and simulator may be deemed successful.
Posted by: dhogaza | February 9, 2010 3:52 PM
Thats not quite correct Dhogaza and if there was any subject i could speak on with some authority it would be this one.
Let me explain further, aeronautical engineers have a very good understanding of the physics of flight or aerodynamics.
So lets say they want to design a new plane a little bit bigger and a little heavier and maybe a litle bit faster than the old one. They can simply use a model as you said to simulate the aerodynamic forces placed on the structures of the plane because in the end not much has changed.
But lets say you wanted to design a plane that could travel at 4 times the speed of sound, at this speed the stresses could not be calculated in a model because we would not know what those stresses would be at this speed. Of course we could still model it but we would have to make some assumptions.
Now rather than just accept the model assumptions as they are and go right ahead and build a plane and hope the wings dont come off in its first flight we can build a scaled down version of our plane, bolt it to a rocket blast it high up into the atmosphere, explode the bolts and let the plane glide (at 4 X the speed of sound) back to the ground taking measurements as we go, its called empirical evidence.
We then use this empirical evidence to get rid of any assumptions in our model, this way we can have confidence in our model results. I will leave the reader to draw any comparisons between this example of a model and the climate version.
Oh and Dhogaza before you go saying this is all made up bull dust, it has already been done.
Posted by: crakar24 | February 9, 2010 8:35 PM
And then he said:
And I had assumed, perhaps foolishly, that the former comment referred to, you know, a member of the general public and scheduled commercial air travel. An excellent assumption on my part as I'm certain that no member of the general public has ever been invited along during initial flight testing, not even in a simulator.
It's all testing and it's all validation. Testing is conducted on materials and components and complete assemblies from the mine mouth to the final finished product. The materials that make a wing are tested, the assembled wing is tested, and then the wing plus aircraft is tested and so on to test flights.
It is all validation prior to allowing the product to be put into use by the general public.
Even in my work, I have found that the computer-language compilers which have been independently tested and validated and certified against the language reference specifications are among the more useful.
Posted by: Dan Hughes | February 10, 2010 5:19 AM