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Post by icefisher on May 21, 2009 18:44:49 GMT
the thing is doomed in the first few lines. . . .no ocean model. Climate modeling has been reduced to guys like Hansen saying the warming is in the ocean and the measurements are incorrect and not picking it up. In other words folks. . . . . the best available science says CO2 isn't an issue and that Hansen is wrong. Indeed you can complain the science is inadequate but there isn't much more to say about greenhouse effects until we have a new ocean monitoring system complete with a few years to work the bugs out and ground truth it. Even if we get a Super El Nino Hansen has acknowledged the inadequacy of the monitoring. Steve has expressed astonishment that the science community would overlook obvious stuff. But here we have a golden example of how they overlooked for a couple of decades having adequate monitoring of the most important source of heat accumulation on this planet. I mean this is the equivalent of forgetting your anniversary. They are dog meat.
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Post by socold on May 21, 2009 18:56:56 GMT
the thing is doomed in the first few lines. . . .no ocean model. Because this is the documentation of the atmospheric model. The documentation of the ocean model, and the coupling between them is at other urls.
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Post by tacoman25 on May 21, 2009 20:03:16 GMT
Well then, the models MUST BE perfect and undoubtedly realistic! Wish they would transfer these perfect calculations over to weather models, since they tend to lose accuracy quickly into the future... This is moving on from nautonnier's original claim that the scientists somehow ignore evaporation and convection. The hydrological cycle is reasonably well modelled (that's what the forecast models do). This is what helps define the temperature and humidity profile of the atmosphere. The uncertainty is in the small changes to the cycle that occur as a response to warming and which affects the radiative balance by changing water vapour levels and clouds. When it comes down to it though, the earth is roughly a closed system except for radiation in and radiation out. And the amounts of radiation in and radiation out at any one time are not affected by the amount of energy being shifted about the sysem through convection and the like at that same moment. Ok...so then why have there been vast natural differences in climate in earth's history?
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Post by Pooh on May 21, 2009 21:24:17 GMT
The uncertainty is in the small changes to the cycle that occur as a response to warming and which affects the radiative balance by changing water vapour levels and clouds. ... And the amounts of radiation in and radiation out at any one time are not affected by the amount of energy being shifted about the sysem (sic) through convection and the like at that same moment. Ok...so then why have there been vast natural differences in climate in earth's history? Perhaps the models have no clue about storage, lags in response, or the chimney-like Iris effect. Or perhaps the differences are due to having half-vast models? socold, I took a look at your link reference: "Eulerian Dynamical Core"? Differential and integral equations with gradients as terms? Undefined terms? This Forum is not a mushroom farm. I was once presented with a page of formulas as a customer requirement. I looked it over and asked her if what she wanted was "present value". It was. Take-home: Don't present "How" without presenting "What" and "Why" first.
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Post by icefisher on May 21, 2009 23:52:37 GMT
the thing is doomed in the first few lines. . . .no ocean model. Because this is the documentation of the atmospheric model. The documentation of the ocean model, and the coupling between them is at other urls. So they scab in parameters from ocean models, good for them. When do you think they are going to get the ocean models fixed after finding out the ocean is not working as predicted?
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Post by steve on May 22, 2009 11:13:28 GMT
the thing is doomed in the first few lines. . . .no ocean model. Climate modeling has been reduced to guys like Hansen saying the warming is in the ocean and the measurements are incorrect and not picking it up. In other words folks. . . . . the best available science says CO2 isn't an issue and that Hansen is wrong. Indeed you can complain the science is inadequate but there isn't much more to say about greenhouse effects until we have a new ocean monitoring system complete with a few years to work the bugs out and ground truth it. Even if we get a Super El Nino Hansen has acknowledged the inadequacy of the monitoring. Steve has expressed astonishment that the science community would overlook obvious stuff. But here we have a golden example of how they overlooked for a couple of decades having adequate monitoring of the most important source of heat accumulation on this planet. I mean this is the equivalent of forgetting your anniversary. They are dog meat. You didn't need socold to go out and find an example model for you. You could have found a number of them yourself quite easily. So why look at what socold has found, and criticise it, without trying to find out more yourself? Two comments: 1. As I've said before, models are tools that can be used in many different ways to understand processes that go on in the earth system. You don't need to model everything for every experiment. 2. These days, many models are modular, and connected together by couplers. An atmosphere can be run by itself forced by a sea surface temperature dataset, or it can be run alongside different ocean models. [quick google...] here is the coupler for the CCSM model: www.ccsm.ucar.edu/models/ccsm3.0/cpl6/
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Post by magellan on May 22, 2009 11:34:48 GMT
the thing is doomed in the first few lines. . . .no ocean model. Climate modeling has been reduced to guys like Hansen saying the warming is in the ocean and the measurements are incorrect and not picking it up. In other words folks. . . . . the best available science says CO2 isn't an issue and that Hansen is wrong. Indeed you can complain the science is inadequate but there isn't much more to say about greenhouse effects until we have a new ocean monitoring system complete with a few years to work the bugs out and ground truth it. Even if we get a Super El Nino Hansen has acknowledged the inadequacy of the monitoring. Steve has expressed astonishment that the science community would overlook obvious stuff. But here we have a golden example of how they overlooked for a couple of decades having adequate monitoring of the most important source of heat accumulation on this planet. I mean this is the equivalent of forgetting your anniversary. They are dog meat. You didn't need socold to go out and find an example model for you. You could have found a number of them yourself quite easily. So why look at what socold has found, and criticise it, without trying to find out more yourself? Two comments: 1. As I've said before, models are tools that can be used in many different ways to understand processes that go on in the earth system. You don't need to model everything for every experiment. 2. These days, many models are modular, and connected together by couplers. An atmosphere can be run by itself forced by a sea surface temperature dataset, or it can be run alongside different ocean models. [quick google...] here is the coupler for the CCSM model: www.ccsm.ucar.edu/models/ccsm3.0/cpl6/You are avoiding the issue again. Climate models are highly parametrized (fudged), so why keep pretending they aren't?
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Post by steve on May 22, 2009 12:07:03 GMT
Magellan,
How am I avoiding the issue. Comment 1 in my last post pretty much says what you did.
You are avoiding the issue, that climate models have been highly useful in improving the understanding of many processes in the atmosphere.
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Post by magellan on May 22, 2009 12:48:31 GMT
Magellan, How am I avoiding the issue. Comment 1 in my last post pretty much says what you did. You are avoiding the issue, that climate models have been highly useful in improving the understanding of many processes in the atmosphere. Socold and other warmers argue climate models are predictive tools and contain the relevant physics accurately to simulate weather/climate. Do you agree or disagree that climate models are highly parametrized? A simple yes or no will do.
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Post by icefisher on May 22, 2009 12:51:00 GMT
Magellan, How am I avoiding the issue. Comment 1 in my last post pretty much says what you did. You are avoiding the issue, that climate models have been highly useful in improving the understanding of many processes in the atmosphere. Indeed Steve. They have taught us the Al Gore claim that CO2 warming had overridden natural variations was a complete load of crap! LOL!
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Post by steve on May 22, 2009 14:42:22 GMT
Magellan, How am I avoiding the issue. Comment 1 in my last post pretty much says what you did. You are avoiding the issue, that climate models have been highly useful in improving the understanding of many processes in the atmosphere. Indeed Steve. They have taught us the Al Gore claim that CO2 warming had overridden natural variations was a complete load of crap! LOL! I think there should be a new variant on Godwin's law that applies when people bring up things that Al Gore is alleged to have said.
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Post by Pooh on May 22, 2009 15:11:37 GMT
Indeed Steve. They have taught us the Al Gore claim that CO2 warming had overridden natural variations was a complete load of crap! LOL! I think there should be a new variant on Godwin's law that applies when people bring up things that Al Gore is alleged to have said. No, Steve. "Godwin's Law" does not apply where the reference is appropriate to the issue. This Board and Topic is appropriate. (BTW, "Godwin's Law" remains a meme to shut down discussion; it is not a "Law".) Besides, the AGW adherents already have such memes: "the science is settled", "incontrovertible", "as every thinking person knows", .... I grant that icefisher might have cited the source of Al Gore's comment to salve your doubt that he actually said, published or testified to it.
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Post by steve on May 22, 2009 15:12:50 GMT
Magellan, How am I avoiding the issue. Comment 1 in my last post pretty much says what you did. You are avoiding the issue, that climate models have been highly useful in improving the understanding of many processes in the atmosphere. Socold and other warmers argue climate models are predictive tools and contain the relevant physics accurately to simulate weather/climate. Do you agree or disagree that climate models are highly parametrized? A simple yes or no will do. What do you mean by "highly parametrized"?
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Post by kiwistonewall on May 22, 2009 15:31:42 GMT
Trying to be constructive here.
The term "Scientific model" is properly used to refer to a set of concepts and equations which define a theory. Gravity is such a model. The force of gravity (as modelled) is governed by the inverse square law, and experiments show that (within experimental error) this is indeed followed, given the assumptions that (a) we are not dealing with very small objects, and (b) the objects are not moving close to the speed of light.
Our "model" is so close to reality (we think!) that most of us don't talk about gravity being a model. But model it is. Then we had the Bohr & Rutherford models of atoms (useful, but superseded) and so on.
These models are representations of reality, and do help us understand the nature of reality. They can be useful, and give us a grasp on the reality behind the model.
The computer models for weather are entirely different. they are NOT equations based on strict physical laws, but equations based on conjecture and unprovable assumptions. The formula used to compute the model have many parameters. "highly parametrized"
Using iterative procedures, these parameters can be determined from a known set of real data. In other words, given a set of actual climate values, these can be plugged into a computer program, based itself on the modellers conjecture, and a set of parameters (essentially magic numbers) can be derived. So, over a known period of climate, the "model" is forced to accurately fit that climate, using standard methods of curve fitting.
These parameters can then be adjusted (based on whatever the modeller thinks the parameters "mean") and used to create "predictions" of future state by extrapolation. None of these have been remotely successful. Often, they give the parameters many different values, and derive a set of climate futures. Sometimes, one or two of these random predictions closely matches what happens, and this used to show the success of the model.
(I have created these for biological processes, so I do understand the processes). The developer of the model tends to believe passionately in the reality of his/her model, a sort of Pygmalion obsession.
There isn't any reason to conclude that models remotely help us to "understand" climate.
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Post by steve on May 22, 2009 16:38:29 GMT
I like constructive.
Much of the climate model *is* based on and constrained by physical laws - the Navier-Stokes equation, the radiation model, conservation of energy.
Yes there are parameterisations of schemes where there is limited knowledge or computing power or observations. For example, the details of what goes on in the center of a thunderstorm is hard to know, and harder to simulate if your model resolution is high. But these parametrizations are good enough to simulate a reasonable climate in all types of weather and environment (poles, tropics, mid-latitudes).
But I would dispute that you can simply fit your model to all the observations, or that the models are only what they are because they have been fitted to the observations. Yes the models are always needing to be improved, and yes they can be inappropriately fitted to observations, but often the model proves the observations.
I do not think that the models can accurately predict 21st Century climate, and I thought socold held this view too. Fitting the model to the 20th century observations has been useful for focussing on things like the aerosols and the problems with the post-war SST data. But it doesn't prove the models are correct. But not being correct is not the same as being totally wrong. Much of the reason for the uncertainty is lack of knowledge about the impact and amounts of aerosols, not uncertainty in the greenhouse forcings.
So it seems to me that models are going to be correct in calculating the forcing from increased greenhouse gases, and they are broadly correct in predicting approximately constant relative humidity (which will result in a positive wv feedback). This means that we need to be very lucky to find that some negative forcing is going to come out of the woodwork to counteract the warming.
The best evidence that we are likely to hit 2 or 3C warming by the end of the century is from the observations not from the models. Yes the obs are a bit cool at the moment, but it really is too short a period to start talking about cooling or a lot less warming.
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