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Post by donmartin on Apr 8, 2009 22:36:54 GMT
In respect of "models," John von Neumann said, 'give me four parameters and I can tell you everything you wish to know about an elephant. Give me a fifth parameter, and I can show you that the elephant can fly.' ( or words to that effect).
Models and their apparent importance or necessity derive from the easy and simple pragmatism of totalitarian regimes, be they political, scientific, legal, business, or whatever. They avoid judgment, valuation, and rational criticism. They are not the stuff of messy democracy, creativity, and progress.
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Post by socold on Apr 8, 2009 23:50:11 GMT
A physical model is constrained by physics. It's not possible to produce a model of the solar system with planets travelling in elephant shaped orbits for example. I don't believe von neumann was talking about models anyway.
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Post by icefisher on Apr 8, 2009 23:53:04 GMT
A physical model is constrained by physics. It's not possible to produce a model of the solar system with planets travelling in elephant shaped orbits for example. I don't believe von neumann was talking about models anyway. How do you know that the Ptolemaic model didn't have orbits shaped like elephants. As I understand it it had planets moving forward and backwards?
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Post by FineWino on Apr 9, 2009 1:13:32 GMT
A physical model is constrained by physics. It's not possible to produce a model of the solar system with planets travelling in elephant shaped orbits for example. I don't believe von neumann was talking about models anyway. I have not yet posted on this board, as I have not yet felt a need to add to the discussions, but the above statement is SO wrong, I am compelled to respond. socold, REALITY is constrained by physics, and we understand some of the laws of physics better than others, some not at all. That is why the pursuit of science never ends. Models are constrained by nothing except the modeler's imagination. That is why they are models. They are designed in order to test hypotheses about things that we do not understand. Copernicus was a "denier" of the Ptolemeic model of the universe, and was persecuted accordingly. His model was eventually demonstrated to be correct. One COULD design a model of the solar sytem where the planets move in orbits shaped like elephants. We could then compare that model to reality, and reality would disprove the hypothesis that the planetary orbits are shaped like elephants. The scientific method has told us that the model is INVALID. Likewise, if I were to design a climate model that shows the average temperature of the earth increases as the concentration of CO2 in the atmosphere increases, I look to reality to see if my model is valid. If the concentration of CO2 in the atmosphere increases, and the average global temperature does not increase, the model is INVALID. Very simple, end of story. The entire AGW scam is a case of a cadre of dishonest, unethical individuals purporting to practice "science" and convincing an ignorant public that the MODEL is REALITY. Based on your earlier comments and this latest post, I am convinced that you do not understand that the MODEL is not REALITY.
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Post by jimg on Apr 9, 2009 6:00:30 GMT
But if your model that shows temp increasing as CO2 increases.
Then looking to the real world and see the same results doesn't mean that your model is correct. The correlation is there, but it may not be causation.
Are the rising temperatures causing CO2 to increase?
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Post by glc on Apr 9, 2009 8:17:30 GMT
Are the rising temperatures causing CO2 to increase? Almost certainly not. Rising temperatures does result in higher CO2 concentrations, but the temperature rise over the past ~150 years cannot explain the current CO2 increase. Following the last ice age CO2 increased ~100 ppm (180 ppm -> 280 ppm) while temperatures rose more than 5 deg C, i.e. ~20 ppm per deg C. From the Vostock ice core record, Hans Erren found the relationship was ~10ppm per deg C.
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Post by poitsplace on Apr 9, 2009 9:14:29 GMT
Are the rising temperatures causing CO2 to increase? Almost certainly not. Rising temperatures does result in higher CO2 concentrations, but the temperature rise over the past ~150 years cannot explain the current CO2 increase. Following the last ice age CO2 increased ~100 ppm (180 ppm -> 280 ppm) while temperatures rose more than 5 deg C, i.e. ~20 ppm per deg C. From the Vostock ice core record, Hans Erren found the relationship was ~10ppm per deg C. While I agree that MOST of the increases we've seen are from man's emissions, some may have come from degassing. A more likely scenario is that temperature increases have been lowering the uptake of CO2 by the oceans. It's a similar concept but most certainly a different concept. If we do enter into a cooling period as pronounced as the warming period (just a what-if here, not a prediction) I do think that between the elevated CO2 levels and increased solubility that CO2 uptake may increase so much that it might completely stall CO2 increases. It's a fairly unimportant point of course. The CO2 probably isn't contributing much (if anything) to global temperatures anyway.
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Post by icefisher on Apr 9, 2009 13:24:04 GMT
Are the rising temperatures causing CO2 to increase? Almost certainly not. Rising temperatures does result in higher CO2 concentrations, but the temperature rise over the past ~150 years cannot explain the current CO2 increase. Following the last ice age CO2 increased ~100 ppm (180 ppm -> 280 ppm) while temperatures rose more than 5 deg C, i.e. ~20 ppm per deg C. From the Vostock ice core record, Hans Erren found the relationship was ~10ppm per deg C. Do you have a source on that GLC?
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Post by icefisher on Apr 9, 2009 13:29:12 GMT
A physical model is constrained by physics. It's not possible to produce a model of the solar system with planets travelling in elephant shaped orbits for example. I don't believe von neumann was talking about models anyway. How do you know that the Ptolemaic model didn't have orbits shaped like elephants. As I understand it it had planets moving forward and backwards? Come to think of it. . . .with those IR emissions bouncing around like a pong game. . . .maybe they are making shapes like elephants. ;D
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Post by steve on Apr 9, 2009 13:52:16 GMT
Are the rising temperatures causing CO2 to increase? Almost certainly not. Rising temperatures does result in higher CO2 concentrations, but the temperature rise over the past ~150 years cannot explain the current CO2 increase. Following the last ice age CO2 increased ~100 ppm (180 ppm -> 280 ppm) while temperatures rose more than 5 deg C, i.e. ~20 ppm per deg C. From the Vostock ice core record, Hans Erren found the relationship was ~10ppm per deg C. While I agree that MOST of the increases we've seen are from man's emissions, some may have come from degassing. If you calculate the extra amount of CO2 in the air each year and compare it with CO2 emissions calculated from statistics of oil, coal and gas burning, you find that the latter is 2 to 3 times larger than the former. So there is definitely no room for "degassing.
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Post by steve on Apr 9, 2009 14:04:10 GMT
Although the climate models may be made on physical processes, that doesn't mean that assumptions were not made. Yes I agree. Assumptions are made that certain processes do not affect the climate - eg. levels of cosmic rays. If someone proves that cosmic rays have an effect, they can be added to the models to see what effect they have. [/quote] What has been seen as occuring in the climate that has been attributed to CO2 is much more likely the combined effect of many other forcings/feedbacks that we don't fully understand yet. 5 percent off in magnitude here and there would add up. But since we don't understand it, it must be CO2.[/quote] No that is wrong. The effect of CO2 has a physical basis that appears to be strong enough to cause the observed warming. Assuming the CO2 effect has been somehow modelled wrong and that really the warming is caused by an UNKNOWN PROCESS, is merely invoking a god-of-the-gaps type argument. I'm not claiming that we can map our destiny. I'm claiming that it is obvious that CO2 must cause warming, it is obvious that warming is occurring, it is obvious that there are few other validated explanations for the warming.
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Post by steve on Apr 9, 2009 14:36:29 GMT
Well my antenna has gone up! The models are not built on recent warming. Predictions of warming due to increased greenhouse gases were made in 1896 and refined in the 1960s and 1970s long before there was a discernable warming trend. It seems clear (also from your further post) that you don't understand the difference between a climate model and the sorts of models you have used. Can you give me a definition of a "proxy model" by the way. Are they some sort of database full of assumptions? Things like this *are* used in climate modelling - I guess the emissions scenarios that the economists came up with might be counted as "proxy models" of the behaviour of human society. The big difference I see with economic models is that climate models are by and large driven by physics, and the physical laws are fixed. If you have an economic model that tells you that inflation-targetting will improve stability such that central banks start to follow such a policy, then somewhere along the line people's behaviour changes to assume such stability and to take more risks. This change in behaviour breaks the assumptions that were used in the economic model rendering it useless. I would suggest it is you in fact that doesn't understand the difference between a financial model and a climate model in structure and probably also in presentation. The answer is very little. When doing a model to project the future you might include a variable for the democrat party moaning about the economy and you might manifest it in the model as a GDP growth rate from loss of consumer confidence that occurs periodically. A "better" financial long term model will do this as these events are periodic to some degree. It would look like a PDO estimate. . . .but it granted PDOs appear a lot more set in a cycle than democrats moaning about the economy. Did the climate models do this? Well no for the most part. Dr Easterbrook did it though. Now he didn't do that based on physics he did it based upon some knowledge of the cyclical nature of the PDO just like the economic modeler would do it. When it comes to actual physics in the model, financial models have lots of similarities there too. Amortization rates, interest rates, balloon payments, current tax rates, principal are all known stuff, some just at the start others throughout the model. Other things that might affect your model that can be less cyclic might be inflation, future tax rate increases, and prepayments. These are usually afforded a special place in the model where the modeler will make multiple runs based upon different assumptions. Because the import thing about these models is they can alert you to sensitivity or in other words risk. In the climate model this might include cloudiness and precipitation or irradiance, or even maybe CR. For this stuff no physics or cycles might be known. . . .in the case of CR maybe no affect is known. . . .but that doesn't mean there are no estimates of what it might be. . . .so a good model would at least examine it. Some times financial models just leaves stuff out, I already mentioned that regarding typical derivative models and its abundantly clear that climate models do the same thing. Your typical financial guru purchaser usually runs the models with lots of assumptions to get a feel for the investment sensitivity. Its a good way of judging risk. But when the same guru uses the model to sell the investment they might try to argue for the set of assumptions that gets the best price. Often they will even try to enlist their CPA into signing off on it. . . .which the CPA never does if he is focused on staying licensed. . . .though they often pay their CPAs a lot of money to help them develop these models in the first place. Now you tell me what major difference or similarity I haven't acknowledged. I've told you the differences. Financial models are based on confidence, sentiment, and other emotional and fickle things as well as on current circumstances that are different from last year and will be different from the next. Todays model wouldn't work in the 1970s world of nationalised industries, government controlled pay and exchange rate controls, and of course they didn't predict the credit crunch. But if you took a climate/forecasting model, along with your observation network, back to 1000AD or even the last interglacial, and ran a forecast, then likely you would get an acceptable result. Yes PDO might be hard to model, but the impact of PDO can be assessed through detailed observations, and these observations can be used to drive a climate model to see the physical effects on other parts of the system. You could not run a current model to see the effect of a credit crunch in the 1970s because the 1970s was an era of virtually continuous credit crunch where a small proportion of people owned their own houses, and you had to worship your bank manager to get a mortgage.
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jtom
Level 3 Rank
Posts: 248
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Post by jtom on Apr 9, 2009 15:52:12 GMT
Dr. Willie Soon, an Astrophysicist at the Harvard-Smithsonian Center for Astrophysics, "Based on my research, I tend to be in support of a very, very strong role by the Sun's energy input as a climate driver. If you were to ask me about the role of CO2, I would say its very, very small," he added. wbztv.com/local/solar.min.sunrise.2.979838.htmlConsidering that the sun has been the subject of worship in many cultures, then I guess this IS invoking a 'God-type' argument!
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Post by gridley on Apr 9, 2009 16:54:14 GMT
gridley: I don't think the heat flux / resistor analogy works. I'm going to take that as "I don't think the analogy applies" since the method is used in basic thermodynamics and works extremely well in a number of cases. The electrical analogue is a basic tool of thermodynamics, but like most tools does not apply to every case. I'm happy to stipulate that the atmosphere isn't one of them.
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Post by jimg on Apr 9, 2009 17:02:32 GMT
And given that the current trend is to eliminate any God/gods from society, it is only fitting that the sun has little effect. ;-)
Steve, you said that the earth is warming. Don't you mean "was" warming? Given that the current trend has reversed course?
Will it continue?
Now that is the multi-million dollar question.
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