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Post by icefisher on May 18, 2010 0:40:19 GMT
There is no separation. Climate is deterministic and chaotic. I think you are confusing determinism with predictable This discussion is about what is predictable and what is not. You might want to run away from that but I suspect you will be back supporting yet another prediction. and you seem to also be thinking of determinism vs free will, which is rather irrelevant to this topic. Explain why it is irrelevant. I have no idea to be honest, I just didn't see where the evolution and creator part of the discussion came from. I was discussion metaphysics which is relevant to all science even if not well understood. Religious beliefs step into discussions when one begins to argue conceptually like in your comment: "No, I am saying that cloud properties are deterministic and depend on things like temperature, humidity, etc. Cloud properties won't just change on their own by magic. It will require a change in temperature, humidity, etc. Any sustained change (many decades) will require a sustained change in temperature, humidity etc. That will require a globally sustained external forcing. Temperature cannot stay elevated without additional energy coming into the system."
In the above comment you assume temperatures are elevated. They may well be adjusting from an anomalous low. A hundred years and a 1% difference in cloud cover isn't sufficient to claim anything unusual without even understanding where heat goes on the planet. You say it isn't magic but you look as befuddled as a magician's audience. I would suggest thats exactly what magic is and you are a victim of it. So you resort to GCMs to explain it to you. That is beyond metaphysics and very clearly into the territory of religion.
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Post by icefisher on May 18, 2010 4:40:55 GMT
There is no separation. Climate is deterministic and chaotic. I think you are confusing determinism with predictable and you seem to also be thinking of determinism vs free will, which is rather irrelevant to this topic. I have no idea to be honest, I just didn't see where the evolution and creator part of the discussion came from. SoCold - (sit down now) I am going to agree with you - in many ways you could claim that Chaotic systems are deterministic. BUT (note the big BUT) .... for an observer to be able to _Predict_ the behavior of the chaotic atmospheric system is not possible. This is because not all the variables are known (we do not know anywhere all there is to know about the behavior of the atmosphere) nor are the precise states of all the variables known and even the smallest tiniest difference in initial state can make the chaotic behaviors totally different. Some of these variables exhibit a 'Levy flight' behavior that _might_ be caused by some other potentially deterministic variable but they are not all known yet and even if they are their behavior is not forecastable. So yes the system may be deterministic to the extent that you can look back and after much work - you _ might_ be able to have some inkling _why_ it did what it did; but there is no chance whatsoever of forecasting what it will do from our current position of ignorance. You appear to be under the misapprehension (or faith) that a simple single vector applied in one direction will _eventually_ cause a similarly simple deterministic behavior in a complex chaotic system. This is not a hypothesis I have seen proven. Good post but I would leave out the part about "that Chaotic systems are deterministic. " While I agree this is the only point you agreed with Socold on, the definition of "deterministic" is "not random". So a deterministic chaotic system is an oxymoron.
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Post by poitsplace on May 18, 2010 7:13:50 GMT
A common mistake, icefisher. Deterministic does in fact mean "not random" (more or less) but it doesn't say anything about a system being "unpredictable".
Random means even (magically) knowing and somehow being able to compute to infinite precision the interactions...we could not work out what was going to happen.
Unpredictable can be random...but it can also mean you simply lack sufficient knowledge to work out the resulting behavior.
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Post by latecommer on May 18, 2010 16:54:32 GMT
I can think of a very easy solution to judging the reliablity of these models...give us a 1 year, 5 year, 10 year, and 20 year prediction of real climate on the virtual climate machine which is the GMC. In ten years we will have a pretty good idea of how reliable it is. I know that climate has to judged on a longer term, but the cowardice of predicting something one can never be called on deserves to be noted and the conclusions simply ignored.
Since there is no evidence that man has adversley effected climate, and since models are NEVER EVIDENCE, there is no evidence period.
If you further consider that today's climate is not the optimal climate for man; I am pulling very much for a general warming over the next century, and trusting the established model of climate, not the totally failed hypothesis of AGW, leads me to believe I will be disappointed.
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Post by nautonnier on May 18, 2010 23:12:09 GMT
SoCold - (sit down now) I am going to agree with you - in many ways you could claim that Chaotic systems are deterministic. BUT (note the big BUT) .... for an observer to be able to _Predict_ the behavior of the chaotic atmospheric system is not possible. This is because not all the variables are known (we do not know anywhere all there is to know about the behavior of the atmosphere) nor are the precise states of all the variables known and even the smallest tiniest difference in initial state can make the chaotic behaviors totally different. Some of these variables exhibit a 'Levy flight' behavior that _might_ be caused by some other potentially deterministic variable but they are not all known yet and even if they are their behavior is not forecastable. So yes the system may be deterministic to the extent that you can look back and after much work - you _ might_ be able to have some inkling _why_ it did what it did; but there is no chance whatsoever of forecasting what it will do from our current position of ignorance. You appear to be under the misapprehension (or faith) that a simple single vector applied in one direction will _eventually_ cause a similarly simple deterministic behavior in a complex chaotic system. This is not a hypothesis I have seen proven. Good post but I would leave out the part about "that Chaotic systems are deterministic. " While I agree this is the only point you agreed with Socold on, the definition of "deterministic" is "not random". So a deterministic chaotic system is an oxymoron. Then you will have to join the ranks of the non-mathematicians who use chaotic and random as synonyms. A chaotic system IS deterministic - its just that a complex chaotic system behavior cannot be forecast (unless you are Laplace's Daemon) See en.wikipedia.org/wiki/Chaos_theory and 'What is the Difference Between Random and Chaotic Sequences In everyday language, people tend to use the words “random” and “chaotic” interchangably. You will recall from the text that chaotic sequences are in fact generated deterministically from the dynamical system xn+1 = f(xn)" www.math.tamu.edu/~mpilant/math614/chaos_vs_random.pdfThere's lots more - chaos theory is a really interesting area to study
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Post by scpg02 on May 19, 2010 3:54:07 GMT
Good post but I would leave out the part about "that Chaotic systems are deterministic. " While I agree this is the only point you agreed with Socold on, the definition of "deterministic" is "not random". So a deterministic chaotic system is an oxymoron. Then you will have to join the ranks of the non-mathematicians who use chaotic and random as synonyms. A chaotic system IS deterministic - its just that a complex chaotic system behavior cannot be forecast (unless you are Laplace's Daemon) See en.wikipedia.org/wiki/Chaos_theory and 'What is the Difference Between Random and Chaotic Sequences In everyday language, people tend to use the words “random” and “chaotic” interchangably. You will recall from the text that chaotic sequences are in fact generated deterministically from the dynamical system xn+1 = f(xn)" www.math.tamu.edu/~mpilant/math614/chaos_vs_random.pdfThere's lots more - chaos theory is a really interesting area to study It also made for an interesting character played by Jeff Goldblum.
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Post by poitsplace on May 19, 2010 8:25:38 GMT
Has anyone checked into the models' moisture content data? Someone commented in another thread about the simple temperature being a poor measure and temperature plus water vapor content (or latent heat) being a better measure of heat...which made me think about how models would have to get both areas right to be remotely correct. I seriously doubt they did.
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Post by icefisher on May 19, 2010 12:37:44 GMT
Good post but I would leave out the part about "that Chaotic systems are deterministic. " While I agree this is the only point you agreed with Socold on, the definition of "deterministic" is "not random". So a deterministic chaotic system is an oxymoron. Then you will have to join the ranks of the non-mathematicians who use chaotic and random as synonyms. A chaotic system IS deterministic - its just that a complex chaotic system behavior cannot be forecast (unless you are Laplace's Daemon) See en.wikipedia.org/wiki/Chaos_theory and 'What is the Difference Between Random and Chaotic Sequences In everyday language, people tend to use the words “random” and “chaotic” interchangably. You will recall from the text that chaotic sequences are in fact generated deterministically from the dynamical system xn+1 = f(xn)" www.math.tamu.edu/~mpilant/math614/chaos_vs_random.pdfThere's lots more - chaos theory is a really interesting area to study You have to love it when somebody names someone like a fat guy. . . .Slim. Indeed there are what is known philosophically as compatiblists; which might better be described as a "comfort zone" since the scientific method requires experimentation to establish cause and effect and a chaotic system defies it. Here comes the Al Gore sandpile theory. I can only imagine what ran through Al's mind when he read about the flapping wings of a butterfly in Brazil causing a tornado in Texas and arrived at the conclusion you just can't allow a bunch of ruffians to run loose because you do not know what damage they can wreck.
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Post by magellan on May 19, 2010 23:29:08 GMT
Then you will have to join the ranks of the non-mathematicians who use chaotic and random as synonyms. A chaotic system IS deterministic - its just that a complex chaotic system behavior cannot be forecast (unless you are Laplace's Daemon) See en.wikipedia.org/wiki/Chaos_theory and 'What is the Difference Between Random and Chaotic Sequences In everyday language, people tend to use the words “random” and “chaotic” interchangably. You will recall from the text that chaotic sequences are in fact generated deterministically from the dynamical system xn+1 = f(xn)" www.math.tamu.edu/~mpilant/math614/chaos_vs_random.pdfThere's lots more - chaos theory is a really interesting area to study You have to love it when somebody names someone like a fat guy. . . .Slim. Indeed there are what is known philosophically as compatiblists; which might better be described as a "comfort zone" since the scientific method requires experimentation to establish cause and effect and a chaotic system defies it. Here comes the Al Gore sandpile theory. I can only imagine what ran through Al's mind when he read about the flapping wings of a butterfly in Brazil causing a tornado in Texas and arrived at the conclusion you just can't allow a bunch of ruffians to run loose because you do not know what damage they can wreck. Clouds are deterministic, they just can't be modeled in a GCM
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Post by nautonnier on May 20, 2010 16:29:05 GMT
Some pertinent quotes:
Laplace's Daemon:
"An intelligent being who, at a given moment, knows all the forces that cause nature to move and the positions of the objects that it is made from, if also it is powerful enough to analyze this data, would have described in the same formula the movements of the largest bodies of the universe and those of the lightest atoms." P.-S. Laplace Theorie Analytique des Probabilitès (Courier, Paris, 1820)
"the reductionist hypothesis does not by any means imply a ''constructionist'' one: The ability to reduce everything to simple fundamental laws does not imply the ability to start from those laws and reconstruct the universe." P.W. Anderson More is Different, Science 177 393 (1972)
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Post by trbixler on May 22, 2010 13:42:51 GMT
"Is Global Warming Really Cause for Alarm?" As they say, follow the money. Remember Indiana Jones’ immortal words: “Fortune and glory.” "Equally interesting, the researchers based their findings not on actual experiments, but on yet another computer model that allegedly predicts future temperatures. When they tweaked various assumptions about the physiological effects of CO2, global air temperature over land increased 0.7 degrees F (0.4 deg C) above what supposedly would occur just from doubled CO2 levels directly increasing the greenhouse effect. But just six months earlier, the same authors tweaked the same model differently – and got only 0.2F (0.1 deg C) of additional warming. The authors now say this earlier result is “unrealistic.”" icecap.us/index.php/go/joes-blog
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