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Post by enough on Oct 17, 2009 15:20:08 GMT
Here's the reference for the 3.7W/m^2 number. New estimates of radiative forcing due to well mixed greenhouse gases Gunnar Myhre et al GRL 1998 I have read this paper. It is the usual. It says they ran the model and got this result. That is was with in 7% of the other models but theirs is better. Absoluly no insight as to how it works. Only a ref to the NCAR model. S o I am assuming it (NCAR) is the basis for their model. Try reading a discription of the NCAR model and walk away with an understanding. Did you not read this from Goody: "This is more an article of faith than an demonstrable proposition. It is also possible that the numerical complexity hides or introduces it own sources of error, in addition to making it impossible to penetrate the algorithms of another investigator" |
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Post by steve on Oct 17, 2009 15:40:22 GMT
The whole basis of the validity of a 3.7 warming is models. That is the best that we have at this time. That's 3.7 Watts/m^2 forcing, not warming. And there are lots of different types of "model". This is a simple sort that even most of the scientist sceptics accept because it's really not that hard to model if you know the basic structure of the atmosphere to a rough degree. Lots of sceptics like to confuse this sort of modelling with climate models because they know they get more traction this way. But just because one sort of model is hard to do doesn't mean all models are hard. Some of the sceptics think the actual warming would be 1C or less. Most of the scientists think it will be more and could be a lot more. |
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Post by icefisher on Oct 17, 2009 16:28:35 GMT
Everyone agrees about the cloud issue. There is uncertainty but that is not a reason for the whole AGW theory to be ignored or dismissed. Cloud variability is a given but a number of sceptics seem to be relying on the fact that clouds may come to the rescue. They might - but then again they might not. We have not yet got sufficient evidence to say either way. Cloud variability is tied up with wv feedback which some think will be positive others think negative. There is nothing wrong with considering all possibilities. But, the fact is that, if all other factors remain the same, doubling the CO2 concentration is likely to warm the earth by about 1 deg. That shouldn't be a problem. But there's a strong possibility that all other factors will not remain the same. Other factors could act to 1. Enhance the warming 2. Reduce the warming There's your "uncertainty". It's your call. But remember this is not an experiment on another planet. Come to the rescue? Enhance the warming? Reduce the warming? What warming? What warming needs to be reduced? The warming in your imagination? Natural systems are by nature dynamic not static. There is no visible static warming going on. Its like predicting that a sleeping athlete is going to overheat when he starts running. There is zero evidence that is going to happen. One has to marvel at the egos at work here to override basic observing what is going on. Indeed its possible to override natural systems. . . .but step outside bud, look at the climate. . . .there is no radiation deficit! No warming to stop. If you ask me this is more likely the result of watching too many Saturday morning cartoons. |
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Post by jimcripwell on Oct 17, 2009 16:36:46 GMT
steve writes "To save Jim's time, Jim thinks it's all a load of unscientific nonsense,"
This is simply untrue. I dont know whether it is nonsense or sound science. I cannot find the reference, as I have stated over and over again, that proves radiative transfer models can give a valid estimate of radiative forcing. If this reference exists, and it is sound science, then Myhre el al is sound science. Since I suspect the reference does not exist, then I also suspect that Myhre et al is, indeed, nonsense.
However, the warmaholics on this board, e.g. steve, socold and glc, refuse to address the issue of this missing reference. Where is the science to show that radiative transfer models are a valid way of estimating radiative forcing? And why will no-one address this issue? Surely it is fundamental to the whole IPCC approach of relying on radiative forcing as a valid measure of greenhouse effectiveness.
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Post by icefisher on Oct 17, 2009 16:43:50 GMT
That's 3.7 Watts/m^2 forcing, not warming. Even thats an overstatement! Its an imagined forcing that assumes no clouds or other natural systems don't get in the way and block it. What we are dealing with are expert propagandists that build dynamic conclusions into static concepts using our imperfect language. Its a Bernie Madoff illusion as he hands a few investors handfuls of bucks. Its like "look its real"! But its not. Its a con! Bottom line is its too warm when its too warm. This is more about worrying what other people are doing than worrying about what you are doing. Some of the sceptics think the actual warming would be 1C or less. Most of the scientists think it will be more and could be a lot more. What a laugh that is. There was a time when an accountant could vouch for stuff with impunity. . . .but the world decided that it would be better off to limit con games. Today when an accountant vouches for stuff he puts his net worth and his freedom on the line. When scientists decide to do that they will be more convincing rather than just sort of banding together like a bunch of pigs at the slop trough. Today being a scientist is becoming more and more about faith than science. Evidence is seen in the number of errors that the profession is putting out, references to flawed studies as if they were the gospel is really getting out of hand. |
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Post by socold on Oct 17, 2009 17:06:15 GMT
Here's the reference for the 3.7W/m^2 number. New estimates of radiative forcing due to well mixed greenhouse gases Gunnar Myhre et al GRL 1998 I have read this paper. It is the usual. It says they ran the model and got this result. That is was with in 7% of the other models but theirs is better. Absoluly no insight as to how it works. Only a ref to the NCAR model. S o I am assuming it (NCAR) is the basis for their model. Try reading a discription of the NCAR model and walk away with an understanding. Then refer to the NCAR model. Papers build on each other, a paper is a layer on top of other papers, it isn't a spike through an entire discipline. For the validation of the underlying models used you need to look at the model documentation and papers specific to those model. Eg here's one line by line radiative transfer model rtweb.aer.com/lblrtm_description.html |
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Post by steve on Oct 17, 2009 17:14:54 GMT
steve writes "To save Jim's time, Jim thinks it's all a load of unscientific nonsense," This is simply untrue. I dont know whether it is nonsense or sound science. I cannot find the reference, as I have stated over and over again, that proves radiative transfer models can give a valid estimate of radiative forcing. If this reference exists, and it is sound science, then Myhre el al is sound science. Since I suspect the reference does not exist, then I also suspect that Myhre et al is, indeed, nonsense. However, the warmaholics on this board, e.g. steve, socold and glc, refuse to address the issue of this missing reference. Where is the science to show that radiative transfer models are a valid way of estimating radiative forcing? And why will no-one address this issue? Surely it is fundamental to the whole IPCC approach of relying on radiative forcing as a valid measure of greenhouse effectiveness. I've shown you references that test the theory which you've ignored. You've ignored the fact that scientific sceptics who are have the expertise to look into these areas (Spencer, Lindzen) accept the figure. You've ignored the fact that the calculation is no more complicated than rocket science. You've ignored the fact that most astrophysics (which you appear to be happy to accept) is dependent on the same calculations of radiative forcing. You've ignored me when I've pointed out that you've confused this calculation with modelling to ascertain climate sensitivity. |
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Post by radiant on Oct 17, 2009 17:28:19 GMT
As i have shown on the nitrogen oxygen thread C02 emissions will be absorbed in 0.01mm of Precipital Water Vapour or PWV. solarcycle24com.proboards.com/index.cgi?board=globalwarming&action=display&thread=886&page=6#32230Further the lowest concentration of PWV on earth is the exstraordinary low amount found at Ridge 'A' of 0.6mm which is 3 times less that of the South pole itself Upper atmospheric gas IR emmissions cannot penetrate the freezing cold upper trophospheric water to warm the lower atmosphere. Any warmth received from emissions in the upper freezing upper troposphere will be radiated back to space with only a fraction reabsorbed by the gases higher up. There is no mechanism to warm the lower atmosphere because of the extraordinary power of water to absorb frequencies above 1.8 micrometre in only 1mm pmv and frequencies of 10 and above in less than 0.1mm of PWV |
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Post by sigurdur on Oct 17, 2009 17:30:20 GMT
The whole basis of the validity of a 3.7 warming is models. That is the best that we have at this time. That's 3.7 Watts/m^2 forcing, not warming. And there are lots of different types of "model". This is a simple sort that even most of the scientist sceptics accept because it's really not that hard to model if you know the basic structure of the atmosphere to a rough degree. Lots of sceptics like to confuse this sort of modelling with climate models because they know they get more traction this way. But just because one sort of model is hard to do doesn't mean all models are hard. Some of the sceptics think the actual warming would be 1C or less. Most of the scientists think it will be more and could be a lot more. OoOPPPs......proofread Sigurdur.........proofrread. Thank you Steve. I didn't mean to indicate 3.7C of warming......rather the 3.7W of forcing. The rest of the post stands. |
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Post by socold on Oct 17, 2009 17:34:32 GMT
That's 3.7 Watts/m^2 forcing, not warming. Even thats an overstatement! Its an imagined forcing that assumes no clouds or other natural systems don't get in the way and block it. The 3.7wm-2 forcing tells us the imbalance if the climate stays exactly the same but for the doubled co2. The Earth cannot maintain such an energy balance and so the climate has to change. That change is the response to the forcing. See that if there is no forcing, there needn't be a response. The forcing causes the response. Above you propose the climate response would be an increase in cloud cover or some other natural system. That would be a decrease in energy in. That doesn't make the forcing "imaginary". On the contrary: the response can only exist because the forcing is real. A truly imaginary forcing would require no response by the climate. For example if I spit in the air. Zero forcing. The climate can stay the same without going into energy imbalance. |
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Post by radiant on Oct 17, 2009 17:41:28 GMT
Perhaps somebody could be so kind to tell me what altitude all of C02's emissions are absorbed if C02 is absorbed in 0.01mm of Precipital water vapour
Do we have any links to atmospheric water content with altitude please?
Thanks
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Post by glc on Oct 17, 2009 17:50:35 GMT
Come to the rescue? Enhance the warming? Reduce the warming? What warming? What warming needs to be reduced? The warming in your imagination?The warming that's likely to happen (and is probably already happening) from the increase in atmospheric CO2. The ~1 deg warming which will result by doubling the CO2 concentration. The warming that is accepted by most AGW-sceptical scientists including the following: Richard Lindzen, Patrick Michaels, Jack Barrett plus many, many others. Before you jump in with something about Richard Lindzen only thinks we'll get 0.3 or 0.6 or whatever. Richard Lindzen is arguing for negative feedbacks. He openly says that, all other things being equal, the warming will be ~1 deg (*see below), BUT he believes there will be a negative feedback which will reduce the warming (my option 2). He may turn out to be right, but how much of a gamble should we be prepared to take. * In this WUWT post wattsupwiththat.com/2009/03/30/lindzen-on-negative-climate-feedback/Richard Lindzen states "For example, if one simply doubles the amount of CO2 in the atmosphere, the temperature increase is about 1°C".
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Post by glc on Oct 17, 2009 18:05:51 GMT
Once again we see this scientific nonsense. socold keeps on repeating it as well. Just because it is repeated over and over again, does not make it correct. The 1 C rise in temperature as well as the 3.7 wm-2 change in radiaitve forcing for a doubling CO2 are both hypothetical numbers which can never be measured. They are based on the output of non-validated computer programs
They are validated by earth's emission spectra. And why come here and argue why not badger Richard Lindzen about it.
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Post by radiant on Oct 17, 2009 18:22:50 GMT
They are validated by earth's emission spectra. And why come here and argue why not badger Richard Lindzen about it. Where is this 'earths emission spectra'? Can you show me a real earths emission spectra recorded at a known time and viewing a known location with known atmospheric conditions?? |
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Post by glc on Oct 17, 2009 18:29:15 GMT
Steve wrote:
Here's the reference for the 3.7W/m^2 number.
New estimates of radiative forcing due to well mixed greenhouse gases
Gunnar Myhre et al GRL 1998
enough replied
I have read this paper. It is the usual...........
Some time ago I emailed Jack Barrett about a number of climate issues including the Myhre et al 'equation'. This is part of his reply
This simple equation is derived by Excel curve-fitting to data produced from a model for CO2 concentrations between 300-600 ppmv. It is not derived from basis physics, although one might expect the relationship to be logarithmic from the Beer-Lambert Law of light absorption. I don't regard it to be well established, but the IPCC use it as the basis of their predictions. It gives the 'forcing' without any feedbacks and it is those that give rise to the many and varied forecasts of future climate that have been sold to the policy makers. I think the equation is not far from the mark, however, and the MODTRAN program that I use gives similar results, again it is what effects the feedbacks have that give rise to the various predictions. Myhre & Co. altered their initial estimate of the coefficient in their equation, down-grading it by 15% in a later paper (attached).
Regards
Jack
Most of the leading climate scientists have come up with their own independent estimates for 2xCO2 forcing. There is nothing particularly special about the Myhre equation. It's just a simple expression to estimate CO2 forcing. But, as Jack says, it's "not far from the mark".
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