Heat Cannot Be Trapped Because It Radiates Away Constantly
Obviously, the air cools at night. Why would some of the heat be trapped while the rest cools?
Most heat gets into the atmosphere through conduction, convection (wind blowing over the surface) and evaporation. Why doesn't it get trapped? Some scientists used to claim that greenhouse gases are the only means for getting heat into the atmosphere. They stopped saying that recently, but activists didn't notice.
When a molecule of carbon dioxide absorbs radiation, it re-emits the radiation in femto seconds (83 femto seconds at an average wavelength of 25 microns). The time can be calculated based on wavelength of the radiation. Each wave of emitted radiation is a vibration by the molecule emitting it.
A wave of black body infrared radiation being emitted is stronger than a wave of fingerprint radiation being absorbed, which means radiation is emitted as fast as it is absorbed. All matter emits black body infrared radiation constantly. Otherwise, there would be nothing for carbon dioxide to absorb.
Carbon dioxide absorbs 8% of the black body bandwidth, which means it is 8% as strong as the black body radiation being emitted. This is because the "fingerprint radiation" being absorbed by carbon dioxide only influences part of the molecule causing bonds to be stretched, while black body radiation is emitted by the entire molecule as it vibrates between the molecules around it. This means energy absorbed by carbon dioxide is re-emitted as block body radiation as fast as it is absorbed.
This is why "heat trapping gas" had to be contrived as a propaganda statement. If the heat isn't trapped, it can't be spread to the 2,500 molecules around it.
The amount of black body radiation emitted by all matter is based on the temperature as indicated by the Stefan-Boltzmann constant.
As molecules vibrate, they impart some kinetic energy to the molecules which they strike, and they emit some energy as radiation. The exact ratio varies with conditions and is too complex to determine exactly, but it can be guessed at for a rough estimate.
This image shows how energy is re-distributed when radiation is absorbed by carbon dioxide.
When a molecule of CO2 in the atmosphere absorbs fingerprint radiation (the only thing in question) it increases in vibratory motion, which is heat. As it bumps into surrounding molecules (mostly nitrogen gas), it imparts some motion, which reduces its own motion, while increasing the motion of the other molecule. This bumping goes from molecule to molecule, as the energy spreads through the atmosphere.
The vibrating motion of molecules sends out waves of infrared radiation. As the molecular motion decreases, the intensity of the radiation and its frequency get lower.
The amount of such bumping and re-emitting that must occur to lose the energy gained by absorption depends upon how strong the radiation is that is absorbed, which is determined by the temperature of the emitting molecules. Emissions from the surface of the earth into the atmosphere would go from warmer to colder. For short distances in the atmosphere, the emitting temperature would be about the same as the absorbing temperature.
Absorbed radiation (fingerprint radiation) is weaker than emitted radiation (black body radiation), because 8% of black body radiation is fingerprint radiation absorbed by CO2. In the top image, 8% of the horizontal distance is CO2, as tested during the early fifties.
When temperatures are equal for emission and absorption, radiation absorbed by carbon dioxide would be re-emitted within the time required for five wavelengths or bump cycles. Five times 83 femto seconds is 415 femto seconds. But most emission occurs during the first bump, which means the total is closer to 83 than 415 femto seconds.
Why five cycles? CO2 absorbs finger print radiation in three peaks, the strongest one at 15 microns of wavelength. It then emits the energy as black body radiation due to the vibration of the molecules. Weak radiation is absorbed and stronger radiation is emitted, except that kinetic energy (heat, when averaged) is also being imparted to nearby molecules at the same time. Those molecules also emit radiation. By the time five bumps occur, the initial radiation energy would be re-emitted.
Since each CO2 molecule in the atmosphere is surrounded by 2,500 air molecules, it would have to be 2,500°C to heat the surrounding molecules to an average temperature of 1°C, which is absurd. The CO2 molecules cannot be much different in temperature than surrounding molecules.
What would actually occur is that the CO2 would only be heated trillionths of a degree centigrade, and no greenhouse effect would occur. Why trillionths of a degree? Because radiation is extremely weak. It's energy is dissipated in femto seconds. The energy cannot build up. This effect rides on top of normal temperatures, which are mostly produced through conduction, convection and evaporation.
It is equilibrium that determines the temperature of the atmosphere, which is independent of how the heat gets into the atmosphere. Equilibrium means the temperature builds up until the amount of radiation into space equals the amount of radiation entering from the sun. Some persons say greenhouse gases shift the equilibrium temperature upward, but this is where the trillionths of a degree enter in. Radiation would escape into space almost as fast after striking a few CO2 molecules.
All matter is emitting radiation constantly based upon its temperature. The Stefan-Boltzmann constant says the amount of radiation emitted is determined by the temperature for all matter. Small adjustments are made for "emissivity" and "absorptivity."
This means, in the atmosphere, all molecules are approximately emitting the same amount of radiation in a local area where their temperatures are the same. The carbon dioxide is emitting the same amount of radiation as the oxygen and nitrogen, according to the Stefan-Boltzmann constant. The Stefan-Boltzmann constant has a lot of problems with it, but for this purpose, the difference between the radiation emitted by carbon dioxide and nitrogen and oxygen is not relevant.
These atmospheric molecules pick up their energy by bumping into each other, which is conduction. The energy gets into the atmosphere mostly through conduction, convection and evaporation, as wind blows over the surface of the earth. A very small amount, 1-3% of the energy results from absorption of black body radiation. Climatologists attribute 79% of the energy to black body radiation, but the number is so crazy they can't live with it, yet they can't change it, because it is locked in place by an absurd Stefan-Boltzmann constant which shows 20-50 times too much radiation being given off by matter at normal temperatures.
In addition to absorbing black body (wide bandwidth) radiation, all molecules absorb "fingerprint radiation." Usually, the amount of fingerprint radiation is so small that it is considered to be zero. But for some molecules, such as carbon dioxide, it is significant.
The difference between back body radiation and fingerprint radiation is that black body radiation is absorbed by the whole molecule, while fingerprint radiation is absorbed by components of the molecule. With carbon dioxide, the ability of bonds to oxygen to stretch and vibrate causes fingerprint radiation to be absorbed. With nitrogen, the two atoms are locked together more uniformly, so variations do not absorb significant radiation.
The net effect is that all molecules in the atmosphere are emitting radiation constantly and approximately uniformly in a localized area and acquiring energy through conduction and black body radiation constantly and uniformly, while carbon dioxide absorbs fingerprint radiation also.
So the question is, how much temperature increase results from the addition of fingerprint radiation to the energy of carbon dioxide. As the CO2 gets warmer from absorbing fingerprint radiation, it emits more black body radiation due to its increased temperature. At the higher temperature, radiation outflow equals radiation inflow, which is called equilibrium. All dynamic systems in nature adjust to effects upon them through equilibrium, unless something breaks. Energy systems don't break, so they always adjust to equilibrium.
So some climatologists say greenhouse gases shift the equilibrium temperature upward. To some extent, the statement must be a truism. But it is in the trillionths of a degree range, and it is inappropriate to place a significance on nonsignificant numbers, which means it is zero.
The persons who say the equilibrium temperature shifts upward are not only wrong about the significance of zero, they are also wrong in explaining the quantitation derived through radiative transfer equations, which say the number is 3.7 w/m² upon doubling the amount of CO2 in the air. That number is a non-equilibrium number. There is no number for equilibrium. Every molecule shifts its energy slightly to achieve equilibrium. Non-equilibrium is an impossibility for atmospheric energy over time. There are seasonal accumulations of energy, which can offset the equilibrium process for several weeks, but most of that energy is stored in the solid matter on the surface rather than the air.
Why then would the net temperature increase due to CO2 absorbing fingerprint radiation be in the trillionths of a degree range? There is a dynamic explanation and a number crunching explanation.
The dynamic explanation is this: The fingerprint radiation being absorbed would be small compared to the black body radiation being emitted, because only 8% of the black body radiation is fingerprint radiation which can be absorbed by CO2. But the proportionalities don't matter, because even if more radiation is absorbed than emitted, conduction moves the energy to surrounding molecules with each bump, which occurs in about 83 femto seconds at a wavelength of 25 microns. If five molecules are bumped, then five molecules are emitting the radiation instead of just one. It means, for each CO2 molecule absorbing fingerprint radiation, several molecules around it are emitting that energy. With 2,500 air molecules surrounding each CO2 molecule at 400 parts per million CO2, five molecules warming slightly is no significant average increase for the entire atmosphere.
To crunch numbers by a more real method than radiative transfer equations, the known energy quantities have to be divided up into several categories. After dividing several times, the total amount of energy that can be attributed to CO2 is in the trillionths of a degree range. This process is shown on this web page (220x10-12°C).