Basics – Emissivity and the Stefan Boltzmann Equation | The Science of Doom
The Stefan-Boltzmann equation can be derived from Planck's law with some assumptions. However, the emissivity and absorptivity needs to be considered in . I have been tying to get this meme to stick for over a year now. In heat transfer, Kirchhoff's law of thermal radiation refers to wavelength-specific radiative . Average and overall absorptivity and emissivity data are often given for .. "On the relation between the radiating and absorbing powers of different. The term ε' in the Stefan-Boltzmann equation is not really a constant. of the computation with produces the ubiquitous K meme in the box on . I pointed out the difference in directional emissivity/absorptivity of the Earth.
Since neither the earth nor the atmosphere is a big reflector of IR, they are applicable. Yes Tom, and that means that neither of the radiation terms from either surface are heat. It means that heat is only the difference between the energy terms.
The only time energy is heat is when it is the remaining difference between energy terms. The energy is remaining in the system, not being returned to the system. No paper can make those emissions not happen, and no model of the atmosphere can be correct if it does not quantify the emissions of atmospheric molecules and the distribution of energy by altitude that results from them. H2O in all of its phases has much higher heat capacity than most other Earthly substances, hence when H2O is present things will cool and also heat at a slower rate than if they are not present.
It would certainly change the dynamic of surface temperatures, but the earth would still cool quite well again, look how efficient the moon is at shedding heat while only using radiative emission as its method. Radiative greenhouse effect debunked! Thanks for confirming what the Slayers are saying about the deep fraud of climate alarm and its radiative greenhouse effect. Not aware of anyone doing that.
Your description of heat flow and reference to the textbook, and your comments about emissivity, which are identical to what the Slayers have been saying, take into full account the radiative properties of molecules, etc.
I think our efforts have converged, which is great, finally!
A Note on the Stefan-Boltzmann Equation
Not aware of anyone ignoring that there are TWO terms in the radiant heat flow equation, but I am aware of people trying to say that the second cooler term returns heat to the surface and acts like a radiative greenhouse effect, which of course is nonsense as you have kindly explained here.
Temperature and the emitted intensity dependence on it, IS the whole theory. The other included terms like wavelength, grey or black, displacement of the emission curve etc. They are facets on the diamond, but they all obey that relationship. If you say that emission in a investigated situation not is dependent on temperature, our response to that, and your own, should be that you have miscalculated, not to ignore a law that has been standing through most part of the evolution of modern physics.
I think it can be considered to be the strongest consensus there is in all science of all kinds. It is very clearly written, and it consists of so few parts that if you just read every word in that one sentence you know how to apply it. The emission depends on temperature only. Which part of it and why do you say is wrong. A statement about that must be connected to evidence disproving that very mechanism, and as far as I see it, there is only one mechanism in there.
From that law of thermal emission from any body of any kind, we can safely assume that a claim where the emission from a somewhat hot surface depends on the decreased emission of a cold gas surrounding it, can be said to be untrue.
I think this law have been overlooked. It is the entire theory, that radiation depends on temperature, not the other way around. And the other terms are jabout the characteristics of the emission in higher resolution. Heat transfer is the only theory that should be used for temperature and the relation between emitting bodys. It will fit the temperature profile of earth, we can rely on that. It has been standing for a long time. So your warm food is cooling at the same rate in a refrigerator and in a warm room.
The temperature of the surrounding gas matters for the emission of the gas. The emission of the surface depends on its internal state. That is what the theory say.
Kirchhoff's law of thermal radiation
It is a bit misleading to say that it is cooling. The food emits depending on its temperature. Whatever assumption you make, it has to fit that law. Emissivity less than 1 allows us to adjust the S-B equation so that it agrees with observations. The S-B is used to calculate emission of radiation from the surface of the planet. The Schwarzschild equation is derived from Einstein coefficients assuming LTE and those coefficients turn into absorption cross-sections.
Einstein used thermodynamics in general as his base for developing his theory. Non-equilibrium is not helping the greenhouse theory, it makes it worse. That a transparent atmosphere emits and absorbs poorly in relation to solids means that it is colder and emits less heat, or energy overall. Non-equilibrium doesnt make heat go backwards and disconnects temperature from emitted intensity.
If you still claim they do, your have to attach a reference from the theory of thermal radiation, where changes happen that makes the relationship invalid. Emissivity does not allow such processes where temperature is disconnected from emission.
Emissitivity says that emission and absorption is a fraction of the radiation around the body. It is very clearly explained that if absorption is 0. That would be a remarkable discovery.
Radiation properties - Wikipedia
How the radiation is changed happens within the fact proven in many experiments over and over again, that the emission is dependent on temperature alone. It has no function where the emitters internal state is dependent on the absorbing body or molecule.
The emitted intensity is dependent on temperature alone. It has never been questioned or proven wrong. Circumstances sometimes make it less distinct and the term emissivity is used for those situations.
Are you saying that the law of thermal radiation where the emission and absorption is not dependent on the internal state? Technically, you should not use it or the SB eqn where equilibrium does exist — in the atmosphere.
Planck ignores the fact that real molecules absorb and emit different wavelengths very differently. Einstein coefficients encompass these aspects of the behavior of molecules that are ignored by Planck. I would think that if an imbalance happens, it would always involve a relationship between two ore more bodies, and originate from these relations.
It is pretty clear that it is the decrease in the troposphere emission that is the initial cause of temperature rising in the greenhouse theory.