Freeman Dyson:
- The real world is muddy and messy and full of things that we do not yet understand. It is much easier for a scientist to sit in an air-conditioned building and run computer models, than to put on winter clothes and measure what is really happening outside in the swamps and the clouds. That is why the climate model experts end up believing their own models.
Robert Laughlin:
- The geologic record suggests that climate ought not to concern us too much when we’re gazing into the energy future, not because it’s unimportant, but because it’s beyond our power to control.
Edward Teller:
- Society's emissions of carbon dioxide may or may not turn out to have something significant to do with global warming--the jury is still out.
Frederick Seitz:
- Research data on climate change do not show that human use of hydrocarbons is harmful. To the contrary, there is good evidence that increased atmospheric carbon dioxide is environmentally helpful.
Robert Jastrow:
- The scientific facts indicate that all the temperature changes observed in the last 100 years were largely natural changes and were not caused by carbon dioxide produced in human activities.
William Nirenberg:
- The available data on climate change, however, do not support these predictions, nor do they support the idea that human activity has caused, or will cause, a dangerous increase in global temperatures. ...These facts indicate that theoretical estimates of the greenhouse problem have greatly exaggerated its seriousness.
We see that the main skeptical argument used by these eminent physicists is that climate modeling is complex and that observations do not match very well with observations. Fair enough.
But the eminent physicists do not criticize the very physics basis of climate alarmism: the greenhouse effect supposedly resulting from atmospheric backradiation. The mantra that says that doubled CO2 will cause a global warming of 1.2 C, by basic physics which cannot be questioned by anybody eminent or not.
Does it mean that the eminent physicists possess a basic physical theory supporting the mantra of the greenhouse effect and backradiation? No, it does not seem to be the case. It seems that this theory is hanging freely in the air, because upon scrutiny it evaporates into the atmosphere. Maybe it is now time for eminent physicists to make this clear to the World and its people and leaders?
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Good comment. I am amazed to see the amount of scientists conform to the belief that a doubling of CO2 would raise the surface temperature by around 1 degree C because of a positive greenhouse feedback. In the next breath they dismiss AGW with the argument that negative feedbacks are likely to dominate in nature.
SvaraRaderaAnders, 1°C would be expected in the case of no feedbacks. Observations tell us that there are both positive and negative feedbacks in the climate system, and that the net feedback is positive.
SvaraRaderaClaes, it really is bizarre behaviour to pretend that there is no theoretical understanding of the greenhouse effect. It is clear that you are totally ignorant of the literature spanning many decades in this area. That you are ignorant does not, of course, mean that everyone else is.
Ok, if physicists understand GE, why don' t they say that?
SvaraRaderaActually they all criticize climate alarmism. There is no physics basis of "climate alarmism". Basic greenhouse theory is not alarmist. It is an increase of half a degree or so over the next hundred years for a doubling of CO2. It is only with subjective and worthless climate models do they "project" absurd positive feedbacks of multiple degree increases in temperature and all sorts of calls for alarm.
SvaraRaderaRoger observations tell no such thing.
Andrew, just because basic greenhouse theory is not alarmist it doesn't mean that it is correct. If you make scientific statements like "the temperature might increase between 0 and 0.5 degrees over the next century" you havn't said anything scientific. There is no observation to support any thermodynamic effect of CO2 of the kind we are discussing here, therfore the null hypothesis is the best so far.
SvaraRaderaAgree.
SvaraRadera"Ok, if physicists understand GE, why don' t they say that?"
SvaraRaderaThey do. Your attitude seems to be like that of a small child, sticking its fingers in its ears and singing "la la la I can't hear you".
Andrew, one key observation is that the timing of ice ages is related to changes in Earth's orbital parameters. These changes occur extremely slowly, but the transitions from ice age to interglacial happen on a far shorter time scale. This tells us that there is a "tipping point", a physical bound beyond which climate change occurs very quickly.
Anders, the effect of CO2 on infrared radiation was established observationally over 100 years ago.
Roger, I wasn't talking about inrared absorption/emmision of CO2. I was talking about the hypothetical/fictional thermodynamic heatpumping effect of CO2. If you are a strong believer in this, why don't you pump in CO2 between your window panes?
SvaraRaderaNo Roger, I just showed that eminent physicists do not say anything about GE, in partilular do not say that it is a true physical effect. To say nothing about it does not mean that it is real.
SvaraRaderaClaes, denying that anyone has even studied the greenhouse effect is embarrassing. You seem to want to repeat this statement as often as you can. This is only going to turn you into a laughing stock.
SvaraRaderaAnders, please tell me that you can understand why a miles-deep atmosphere and a small gap between two panes of glass might behave differently. If you understand that CO2 absorbs infrared radiation, then what are you failing to understand? What is this "hypothetical/fictional thermodynamic heatpumping effect" that you clearly don't believe in?
Who has shown GE to be real?
SvaraRaderaNot only is appeal to authority a bad type of argument, but in this case Claes is also involved in quote mining. In the same statement by Robert Laughlin you can read:
SvaraRadera"Carbon dioxide from the human burning of fossil fuel is building up in the atmosphere at a frightening pace, enough to double the present concentration in a century. This buildup has the potential to raise average temperatures on the earth several degrees centigrade, enough to modify the weather and accelerate melting of the polar ice sheets."
Given this statements of facts, his last sentence is incomprehensible, except that he seems concerned only with a geological timescale in which all of human history is just an insignificant blip. That's not how we who live here now see it, though.
Claes, all you need to show the reality of GE is to measure the temperature of the Earth at the surface and compare that number to the blackbody temperature as seen from space.
SvaraRaderaUse one thermometer based on Stefan Boltmanns law. Then use another based on the Ideal Gas law. Then discover that they don't match. Then say that an ideal gas is a blackbody. Then blame everything on water vapour and CO2. Then say that all other heat pumps, except the CO2 heatpump of course, violates the 2nd law.
SvaraRaderaConvincing?
No Thomas, it is not that simple.
SvaraRadera"Who has shown GE to be real?"
SvaraRaderaAs always, you simply ignore it when people point out serious flaws in your logic, knowledge and understanding, and ask a different question instead. You've asked this one before, and you can find your answer in "The Discovery of Global Warming" by Spencer Weart.
Anders, I cannot make any sense of your paragraph. I imagine it is supposed to describe what you think the scientific understanding of the greenhouse effect is. If so, you're what is known as "not even wrong".
You are repeating yourself. Time to quit.
SvaraRaderaRoger, it is you who is "not even wrong" and incredibly arrogant to boot about your inability to provide any specific answers to questions beyond "read Weart's book and Arrhenius". Like the other true believers in your AGW religion, you point to a dogma ignorant of the basic laws of thermodynamics as the "proof". Once again, I challenge you to show us on which page Weart details the mathematics of "back radiation".
SvaraRaderaMS, Spencer Weart's book is a popular history of science, not a mathematical review. Did you realise that or not? Try reading the IPCC 4AR, WG1 report, called "The Physical Science Basis", and do bear in mind that in a complex science you are unlikely to find a complete mathematical description on a single page of any paper or textbook.
SvaraRaderaRoger, thanks for making my point - when Claes et al ask for the mathematics behind your claims you tell him to read a popular history of science containing no mathematical description. Now that you have switched to the AR4, I again challenge you to show us the pages containing the mathematics of "back radiation".
SvaraRaderaRoger, Yes indeed I understand why a miles deep atmosphere displays other features than a small gap between window panes. The effect is called gravity. I agree that CO2 has the ability to absorb and emit IR-light, could you though please work out the QED equations or Magnetohydrodynamics to show why it has the ability to transport heat from the stratosphere to the troposhere, when apparently it lacks the ability to transport heat from the colder outside of the window pane to the warmer inside.
SvaraRaderaMS, what do you do when someone preposterously claims that no physicist has ever understood the greenhouse effect? I, personally, point them in the direction of a popular history of the subject. The particular popular history I recommended has hundreds of references to scientific papers for anyone who wants to know more. I never claimed that Weart's book contained any maths at all. You must have misunderstood something.
SvaraRaderaYou do not seem to realise that "the mathematics of "back radiation"" is rather an enormous subject. It's not clear what you are looking for or what you expect. Why does the IPCC WG1 report not suffice?
Anders, you claim to understand the difference between an atmosphere and a small gap between window panes, and yet your last sentence again shows that you don't. And you claim to understand that CO2 absorbs infrared radiation, and yet your words make it clear that you don't. If the atmosphere is emitting radiation, how is the Earth supposed to avoid absorbing some of it? How is it supposed not to get warmer as a result?
Roger, since I presume you like 20th century physics let me try to explain in the language of QED why the heating effect you are talking about is not likely to exist. One of the major discoveries of the 20th century was that photons have momentum and thus its primary function is to excert a force in the direction of its propagation on anything that absorbs it. However, as we know already from Newtons mechanics, every force is associated with another force directed in the opposite direction. In other words, if something goes down, something else must go up. If the atmosphere excerts a radiation pressure downwards it must be compensated by a reaction upwards, thus reducing the pressure from direct molecular interactions (heat conduction). Or to put it in another way: The radiation diagrams that you are referring to are nothing else than diagrams of radiation pressure, not heat transfer. Now, pressure is completely governed by the mass of the parcel above you, and if the force of gravity doesn't equal the upward force the atmosphere expands or contracts. Now I've helped you a little bit on the way, please work out the Navier-Stokes equations from this point and demonstrate why your supposed effect increases the ground temperature.
SvaraRaderaAnders, try calculating the radiation pressure of the radiation and compare it with the conventional pressure. It's a totally negligible effect.
SvaraRaderaThomas, you are right that it is small compared to the total pressure excerted by the atmosphere. The point is though that if you hypothesize radiation diagrams like the GE ones, then it should be treated as a pressure and not as a heat flow. The first thing that happens is that the atmosphere expands, (do not forget that every layer radiates), then maybe by dissipation some of this is turned into heat somewhere. The expansion probably leads to a decrease of temperature at the ground and in the end you probably wind up with an isothermal atmosphere.
SvaraRaderaAnders, radiation pressure is irrelevant. The simple fact is that the atmosphere re-emits energy that it has absorbed. How could it do otherwise? The ground absorbs some proportion of the radiation that falls on it. Again, how could it do otherwise?
SvaraRaderaExtremely basic observations contradict your views. When that happens, your views must change. If they do not, then it turns into a question of faith, not science.
Roger, you ask why AR4 WG1 does not suffice and yet again fail to provide any page numbers which show the mathematics of "back radiation". So I did some more searching and found 2 old posts by Steve McIntyre on his search for the same information and the pathetically poor scientific basis:
SvaraRaderahttp://climateaudit.org/2008/01/04/ipcc-on-radiative-forcing-1-ar11990/
http://climateaudit.org/2008/01/06/ipcc-and-radiative-forcing-3/
All trails lead back to Hansen's "seminal" 1988 paper, which is simply based upon fudge factors:
http://hockeyschtick.blogspot.com/2010/03/hansen-mars-challenge.html
You do not seem to realise that "the mathematics of "back radiation"" is rather an enormous subject. It's not clear what you are looking for or what you expect.
SvaraRadera