I learned the following from the perspective of chemical measurement instrumentation and field theory instead of photonic (i.e., particle with no mass) theory.
When a so-called “greenhouse” gas molecule passes through a field of full spectrum long wave infrared radiation (LWIR), such as that which is continuously upwelling from earth’s surface, the molecule may possibly absorb one or more quanta of LWIR at one or more of its characteristic vibration frequencies at different amplitudes. For absorption of that LWIR to occur, the intramolecular vibration frequencies, that is the vibrations of one atom in the molecule relative to one of more atoms in the same gas molecule, e.g. CO2, must correspond precisely to frequencies/wavelengths in LWIR field and those vibrational bands or quanta in the gas molecules must be at ground state, i.e., must not be already occupied (not excited, not saturated) from previous LWIR absorption.
We know these vibrations, frequencies and wavelengths for almost all known molecules with high certainty by the measurement instrumentation science known as infrared spectroscopy; the mathematics of this technique became very precise and accurate by use of the Fourier transformation infrared spectroscopy (FTIR), a significant improvement compared to previous dispersive spectroscopy techniques.
The CO2 gas molecule in air at standard temperature and pressure (STP, 25C, 1 atm) has 4 possible vibration frequencies(1) which are very precisely and accurately known. Frequencies precisely convert to wavelengths or wavenumbers. If and only if one or more of the CO2 molecule’s 4 vibrational frequencies are at ground state (i.e., in tune – in coherent resonance- with the surrounding gas temperature/pressure) when the molecule intersects with a LWIR field containing the same frequencies, then this CO2 molecule will absorb 1 wavelength of LWIR at the precise frequency that is coherently in tune with one of the 4 specific vibration states of the CO2 gas molecule. Absorbing that LWIR frequency/wavelength at one of those 4 frequencies is considered analogous to absorption of a photon, or a quantum. The result is the frequency of the internal vibration between two atoms in the CO2 is increased by a known quantum, i.e., a measurable frequency and amplitude. There are levels of excitation or quanta for increasing frequency and amplitude but the levels are discrete and change only by discrete quantum shifts between the levels. When the CO2 molecule absorbs a photon or quantum of LWIR, this CO2 molecule is now in an “excited state” where its potential energy is higher than previously. This occurs when a molecule absorbs energy, causing its electrons/bonds and atoms to move to a higher vibration level. Importantly, the absorption event does not change the vector directional velocity of the CO2 gas molecule as it moves through the atmosphere and the LWIR field. Nor does the emission of that photon by itself slow (or cool) the vector velocity of the CO2 gas molecule. The LWIR photon (or wavelength of LWIR) which was absorbed has no mass, so a collision does not change the direction or velocity of the CO2 molecule. Thus the CO2 gas molecule has not been warmed by the absorption of LWIR except in the purest sense of its increase in potential energy above absolute zero Kelvin scale.
Within a tiny fraction of a second after absorption of the LWIR, our CO2 gas molecule in its elevated state will collide with a N2 molecule (based on a probability distribution), or next probably an O2 molecule, or next a surface on earth, or next a water vapor molecule, and so forth down the probability distribution for collisions. Our excited CO2 gas molecule is unlikely to collide with another CO2 gas molecule since CO2 concentration in air is only ~0.04%. When our CO2 gas molecule at its elevated state is flying through air, its velocity and vector direct was determined by the temperature/pressure of the surrounding gases and its last previous collision geometry. Our CO2 gas molecules collides with a N2 molecule (which is also traveling through space at a velocity and vector determined by the temperature/pressure of the surrounding gases and its last previous collision geometry most probably with another N2 molecule), for example, which disrupts the energy status of our CO2 gas molecule. Due to this disturbance, probably the CO2 molecule will emit one wavelength (or photon) of LWIR into 3D steradian space and our CO2 gas molecule will “relax” to its ground state characteristic vibration mode. The wavelength and frequency emitted will exactly the same as that which was absorbed, but the emission is into the surrounding 3D steradian space. The abundance/amplitude (Watts/m2 ) of the LWIR emitted is distributed over 3D steradian space, that is, the total emitted Watts is the same as absorbed and as held in the quantum energy level, but the W/m2 is reduced at any one point very significantly because the total watts is distributed across a much larger area, i.e., the surface of an expanding 3D steradian solid geometric sphere. About 50% of these watts is emitted vertically toward sky and about 50% is emitted toward earth’s surface.
This LWIR emission from our CO2 gas molecule cannot be absorbed by the N2 gas molecule because the N2 molecule (nor O2, nor Ar) has compatible vibration modes. The CO2 vibrations are potential energy which do not change the temperature of the CO2 molecule nor N2 molecule. However, since our CO2 molecule is slightly more massive than the N2 molecule and both are traveling at about the same velocity, then the CO2 molecule may transmit some additional momentum to the N2 gas molecule thus possibly increasing the velocity/temperature of the N2 molecule (depending on the geometry of the collision.)
About 50% of the total radiative emission watts of our CO2 molecule is directed toward the surface, and 50% to the sky. Already we can say that following the second law of thermodynamics the radiative emissions of our CO2 gas molecule cannot heat Earth’s surface.
Only in the “normal” direction (i.e., perpendicular) between Earth’s surface and our CO2 molecule is the wavelength/frequency the same as the LWIR that was originally absorbed by our CO2 molecule. At all other steradian solid angles the wavelength is longer and the frequency is reduced, i.e., the W/m2 is progressively reduced by the steradian math, and steradian angles lengthen the wavelength until eventually the radiation is no longer in the LWIR (heat band). The amplitude of the emitted energy and wavelength of the emitted energy are simultaneously reduced measured at the point incidence. (The distance the LWIR travels also lengthens (red shifts) the wavelength but this does not occur in the short distances of Earth’s atmosphere so far as I know.)
At all angles including normal the watts received at the next object of incidence after emission (a molecule or a surface) is reduced by the math of steradian solid angles, and all of this occurred within a tiny fraction of a second. At sea level, the density of N2 in air is approximately 2.5 x 1025 molecules/m3. The collision cross-section for CO2-N2 collisions is around 0.43 x 10-18 m2. The collision frequency CO2-N2 can be estimated to be around 1011 collisions per second!
Upon collision with another gas molecule, our CO2 gas molecule cannot transfer its potential energy of vibrations to another gas molecule except in the extremely rare instance of a geometrically perfect head on collision with another CO2 gas molecule which also happens to have exactly compatible vibrational bands which are at ground state, not at an elevated excited state. Since these two CO2 molecules are both traveling through the same broad spectrum upwelling LWIR from Earth’s surface, the quantum energy bands of the second CO2 molecule are probably already saturated, and at the elevated state. The result is the familiar log curve of CO2 wherein additional CO2 concentration yields progressively diminishing increases in LWIR absorption since the CO2 bands are mostly already saturated by LWIR from the surface and pervasive water vapor.
When our CO2 at excited vibration state collides with a solid or liquid surface, these vibrations can transfer to the surface matrix and cause increased vibrations and heating of the molecules in the surface matrix. Ocean surface heats slightly for example by the continuous collision of atmospheric gas molecules with ocean surface. [Reflection (or albedo) of LWIR by the surface does not change surface temperature. No energy is transferred to a surface upon light reflection from the surface.] Considering the mean free path of CO2 molecules at sea level (approximately 60-70 nm) and the Earth’s radius (6.371 x 106 m), and a 2D Earth collision surface versus a 3D atmospheric gas matrix with density varying inversely with altitude, the collision frequency between CO2 molecules and the Earth’s surface can be expected to be significantly lower than the collision frequency between CO2 and N2 molecules in the air matrix.
Meanwhile, as earth’s surface is approached, the density of surrounding water vapor, CO2 and other “greenhouse” gas molecules is increasing due to gravity. [Adiabatic thermodynamics must be considered in our heat transfer discussions.] Earth’s surface is continuing to emit broad spectrum LWIR day and night. The LWIR from our CO2 gas molecule will never reach earth’s surface (to supposedly warm it) unless our CO2 gas molecule happens to be only one wavelength above the surface, in which case the watts/m2 incident at the surface will have been significantly reduced as described above. And, most of the wavelength/frequency incident at the surface is not normal/perpendicular to the surface, thus most of the incident radiation will be no longer LWIR (which could be called heat) but instead Far Infrared (FIR) or longer wavelength and lower W/m2 .
The next frequency range longer than LWIR is the Far Infrared (FIR) band. It ranges from approximately 15 micrometers to 1000 micrometers, while LWIR’s range is 8 micrometers to 15 micrometers wavelength. The FIR band is not typically associated with direct warming of the Earth’s surface. Earth’s surface is primarily warmed by shorter wavelength radiation, such as visible light and near infrared, which are absorbed and re-emitted after heat transference processes as longer wavelength radiation in the LWIR thermal range. (It is these heat transference and thermodynamics processes that I hope our group will finally receive deserved consideration rather than the hoax that radiative transfer by CO2 and other greenhouse gases.)
So, we have LWIR (emitted at characteristic wavelengths/frequencies from our CO2 gas molecule) which is directed toward Earth’s surface but the W/m2 of this LWIR has been significantly diminished by more than 50%, meanwhile still continuously upwelling from the surface is a broad spectrum LWIR field of much higher LWIR W/m2 containing the same wavelengths/frequencies of LWIR which were only a moment before absorbed into the vibration bands of our CO2 gas molecule. When these two fields collide, i.e., a high wattage continuously upwelling LWIR field from Earth’s surface intersects with a one wavelength pulse into a steradian solid sphere of very low W/m2 but at the same wavelength/frequency what happens? The result must be consistent with the second law of thermodynamics states which states that heat cannot spontaneously flow from a colder body to a hotter one. Radiation from our CO2 gas molecule cannot heat the Earth’s surface from which that radiation came a moment before.
Holding a mirror at a campfire to reflect heat of the fire back to the fire does not increase the temperature of the campfire; if we could do that, then we would build perpetual energy machines.
The next frequency range after Far Infrared (FIR) is the Terahertz (THz) gap, also known as the Submillimeter band. This range extends from approximately 0.1 to 10 terahertz frequency, or 0.03 to 3 millimeters wavelength. It’s a relatively unexplored region of the electromagnetic spectrum between the microwave and infrared regions. (By comparison, Earth’s emission in the LWIR range is approximately 390 watts per square meter (W/m²). If I recall, John Clauser calculates absorption of LWIR by CO2 gas at 2 W/m2, which will also be the average emission W/m2 after which the W/m2 isreduced to nilas described above.) FIR radiation is not a significant contributor to warming Earth’s surface; it is largely transmitted through the atmosphere and not significantly absorbed by “greenhouse” gases since those characteristic intramolecular vibrational modes do not exist. Incoming solar THz or Submillimeter band radiation is not a significant contributor to warming. Incoming solar THz or Submillimeter band radiation is mostly absorbed by atmospheric gases, particularly water vapor and CO2, in the troposphere. This absorption occurs due to the resonant frequencies of these molecules, which match the frequencies of THz radiation. In the THz range (0.3 THz to 3 THz), the atmosphere is opaque, and most of the incoming solar energy is attenuated within a few meters at the top of the troposphere; this absorption converts the radiation into heat energy but at the top of the troposphere, and looking at the full spectrum of solar radiation received at the top of that atmosphere, note the W/m2 received at the THz- Submillimeter end of the spectrum is minimal. Farther out the spectrum, Earth’s microwave emission is approximately 20 W/m², but this is a result of the Earth’s temperature, not a cause of it.
In summary, LWIR emitted from Earth’s surface is the primary infrared range responsible for warming Earth’s atmosphere, but not Earth’s surface, but the W/m2 of warming of atmosphere is near zero, since, as described above. Radiative transfer from so-called “greenhouse”gases toward Earth’s surface is reduced to nil, and then further reduced by the progressively increasing optical thickness (opacity) due to increasing density of atmosphere to LWIR as the LWIR approaches the surface. FIR, THz, and microwaves play a negligible role in warming at the surface.
A one wavelength/short pulse of low wattage LWIR from our CO2 molecule does not increase the temperature of Earth’s surface due to the continuous LWIR emission upwelling (hotter) surface. However, it is important to point out that the LWIR energy is not destroyed. It is transformed. The LWIR pulse’s W/m2 is distributed over a large steradian solid angle. The LWIR emission pulse is stretched, spread over a time longer duration (i.e., lower frequency). Its wavelength is lengthened, and its frequency is reduced simultaneously. The steradian solid angle of incidence with the surface decreases from 90 degrees normal (i.e., perpendicular) between the molecule and the surface to 70 degree, to 45 degree to 30 degree angle and so forth. Only at the 90-degree perpendicular between our CO2 molecule and Earth’s surface are the wavelength/frequency the same as absorbed and emitted by our CO2 molecule. LWIR (i.e., heat) emitted from the surface cannot be increased by absorbance of surface-directed LWIR radiative emission from greenhouse gases. That would defy the 2nd law of thermodynamics.
The radiation transfer theory is false with regard to the so-called “greenhouse” warming effect in the atmosphere.
Aloha,
Bud Bromley
- FTIR is a powerful analytical instrumentation and software technique that converts the time-domain interferogram into a frequency-domain spectrum, enabling rapid, high-resolution, and sensitive measurements of molecular absorption and emission characteristics. It enables measurement of the exact frequencies/wavelengths and amplitudes of each of the various vibrational modes of a gas molecule when the molecule interacts with infrared light fields. Some molecules, e.g. Argon gas, do not have vibrational modes. Some molecules have multiple different vibration modes, or dipole moments, e.g. CO2 which has 4 characteristic vibration patterns between its atoms, each with its characteristic absorption and emission. You can view a moving image of these modes here: https://www.chem.purdue.edu/jmol/vibs/co2.html
budbromley 