The UN IPCC Sixth Assessment Report, AR6, states that:
A.1. It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.
After describing changes in numerous climate phenomena, the report recommends:
D.1 From a physical science perspective, limiting human-induced global warming to a specific level requires limiting cumulative CO2 emissions, reaching at least net zero CO2 emissions, along with strong reductions in other greenhouse gas emissions. Strong, rapid and sustained reductions in CH4 emissions would also limit the warming effect resulting from declining aerosol pollution and would improve air quality.
However the link between ‘net zero CO2 emissions’ and climate is only by implication with no proven direct causal link to the climate. Why ? Because there is none.
CO2 is a simple molecule with a carbon atom central and in-line between two oxygen atoms. Excluding those containing radioactive isotopes, molecules do not generate heat so CO2 cannot raise the temperature of anything. Our environment consists of molecules in the form of solid, liquid or gas, depending on the temperature. In isolation, they do not generate heat. They are composed of atoms, have mass and are a form of matter. Heat is a form of energy, an entirely different entity which passes continuously from energy sources to energy sinks either as radiation or via molecules as conduction, convection or change of state thereby causing temperature levels dependent on the energy involved.
As well as the usual convective mode, atmospheric CO2 gas has a radiative mode. Its dominant absorption is for the bending mode where the central carbon atom vibrates back and forth at right angles to the line of the molecule on absorbing photon energy within a narrow band centred at a wave number of 2361.5 per cm, that is, wavelength 4.23 microns, frequency 70.8 Tera Hertz.
Practically everywhere on Earth radiates with a spectral peak wavelength less than 4.23 microns, that is, everywhere is hotter than the subsequent 4.23 micron re-radiation emitted by CO2 so it cannot be warmed by that radiation, which is equivalent to the spectral peak wavelength from a source at -80°C. These conditions only occur occasionally over parts of the Antarctic, where the record minimum was -89.2°C at Vostok Station, Antarctica, on July 21,1983.
In describing events related to the Earth’s climate changes, AR6 repeatedly uses the un-physical metric “radiative forcing”. Their definition is:
“Radiative forcing The change in the net, downward minus upward, radiative flux (expressed in W m–2) due to a change in an external driver of climate change, such as a change in the concentration of carbon dioxide (CO2).”
This was given in more detail in the Fourth Assessment Report AR4:
“ ‘Radiative forcing’ is a measure of the influence a factor has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system and is an index of the importance of the factor as a potential climate change mechanism. Positive forcing tends to warm the surface while negative forcing tends to cool it.”
These statements are incorrect. There is no ‘external driver’ or ‘altering the balance of incoming and outgoing energy’ because the radiative forcing measure only applies to in and out in a single direction and ignores the fact that the radiative gases re-radiate in all directions with equally probability. Satellite measurements give the vertical inward radiation from the Sun and the Earth’s outward radiation after being absorbed and re-radiated on the way in and on the way out. The radiative forcing is actually an estimate of the outward radiation emitted in directions other than that of the inward radiation.
The methods of the IPCC imply the continuation of the concepts made during the 19th Century by Fourier, Tindal and Arrhenius of a “Greenhouse Effect” and “back radiation”. The assumption by the IPCC that these are still relevant is not supported by modern evidence. For example the existence of “back radiation” implies that there is some force, unknown to modern science that determines the direction of release of radiation absorbed by the radiative gases. In reality, radiation is released at random in any direction in 3D space. Nor is it ‘trapped’ as energy always moves to matter at a lower energy level, that is, colder. The standard household thermos flask proves that matter cannot heat itself by absorbing its own radiation. It does not make its contents hotter.
It is claimed that without an atmosphere the Earth’s average surface temperature would be -18°C. The current estimate of the Earth’s average surface temperature is +15°, that is 33°C hotter and that is supposedly due to the radiative effect of the so-called ‘Greenhouse gases’ which make up a minute 0.01% of the atmospheric gases. This completely ignores the well tested Universal Gas Laws which say that the temperature is greatest where the pressure is greatest, namely at the Earth’s surface.
If there was such an event as the Greenhouse Effect, closed volumes would continually warm as the opposing surfaces radiated their heat back and forth between each other. The interior of the tombs of the pharaohs in the Nile Valley would have been charred remnants by the time that they were discovered by the archeologists. Changes in the concentration and pressure of atmospheric radiative gases may change their radiative parameters but do not cause the gases to suddenly start generating heat.
The fact is that radiation is traveling in all directions within the Earth’s atmosphere. At the Poles and at sunrise and sunset every day the Sun’s rays are at or near horizontal to the Earth’s surface. On the night side of the Earth there is no inward radiation from the Sun so the radiative forcing is negative and the Earth cools. Each morning the Earth’s surface temperature rises until the Sun reaches its zenith at which point the surface immediately below is receiving maximum radiation before falling to zero at sunset yet the UN IPCC uses a single value for the incoming radiation.
It is not possible to measure the total outward radiation resulting from a single ray of Sunlight striking the Earth surface at a specific time due to multiple scattering within the atmosphere. This is the reason why we see everything in 3D in such detail, surfaces radiate in all outward directions. The reason that we see hills on the horizon is that they emit radiation that travels horizontally to our eye. The reason that we see the underside of a bird or an aircraft as they flew overhead is that the underside radiates down to our eye. Yet this radiation is totally ignored by the IPCC.
The Sixth Assessment Report of the UN IPCC is of no scientific merit, being written for a purely political purpose.
Climate Auditor 