The Thermal Regulation Of Planetary Atmospheres
1) This is the third in a series of short articles which purport to simplify and explain the basic workings of a climate system. It is applicable to any planet with an atmosphere.
I have previously established in my first article (An Accounting Error by Climate Science.) that the entire mass of the atmosphere contributes to the warming of the surface below it.
In my second article (Earth’s Atmosphere Is Warmed Primarily By Molecules That Are Not Greenhouse Gases) established that it is gases which are not so called greenhouse gases that contribute most to the warming effect both in absolute terms and proportionately.
Intrinsic to the whole scenario is the fact that the surface temperature of a planet with an atmosphere is fixed by mass, gravity and insolation alone so that changes in the composition of the atmosphere can have no effect.
The proof is the simple established fact that at the same atmospheric pressure the temperatures within the atmospheres of both Earth and Venus are much the same when simply adjusted for their different distances from the sun.
Their vastly differing atmospheric compositions make no difference.
This article goes on to consider how that must be achieved.
2) If the sole determinants of surface temperature are mass, gravity and insolation then what role is played by upward infrared radiation from the surface (UWIR) and downward infrared radiation from the sky (DWIR)?
3) The proponents of a human effect on climate support their case by suggesting that DWIR from the sky, having been increased by composition changes such as more greenhouse gases then offsets a portion of the naturally occurring UWIR thereby slowing the cooling of the Earth and forcing the equilibrium temperature to rise.
4) But how can that be so if temperature is solely controlled by mass, gravity and insolation?
5) It cannot be so and we must try to work out why.
6) Logic tells us that if an equation doesn’t need an additional term then it should be left out. In this case we have two unnecessary terms (UWIR and DWIR) so the answer must be that in the real world they cancel out.
7) Note that the two terms can only be cancelled out within the atmosphere since there is additionally a flow of energy coming in from the sun which is being transmitted through the atmosphere in parallel and emitted out to space at the same rate as it comes in. UWIR for the purpose of this article applies only to upward UWIR that exceeds the solar flux because it is only that portion of total UWIR that is required to cancel DWIR. My first article described the separate energy processing loop within the atmosphere which is what we are discussing here.
8) Furthermore I have formed some doubts as to whether the concepts of UWIR and DWIR are anything other than mathematical constructs. I think that all they represent is the temperature of the atmosphere when it is in equilibrium at any given level. That temperature must be the net outcome of both UWIR and DWIR cancelling each other out in the atmospheric loop.
9) So what happens if something interferes with the status quo and forces them out of balance? Composition changes in an atmosphere would do just that so there the AGW proponents must be correct. More greenhouse gases would indeed tend to favour one over the other but as I pointed out previously they actually favour UWIR over DWIR for a faster flow of energy to space and thus a net cooling effect. A portion of the UWIR released upward by GHGs gets out to space thereby escaping the atmospheric loop and reducing the total energy content between surface and top of atmosphere.
10) Be that as it may the question then is what would be the system response if any imbalance did develop whether by way of more DWIR or less DWIR relative to UWIR?
11) We have already established that the sole determinant of temperature is mass, gravity and insolation so there must be an effective negative system response otherwise atmospheres could not be retained long term.
12) The answer is that due to any such imbalance the normal equilibrium distribution of Kinetic Energy (KE) and Potential Energy (PE) is upset and parcels of air start to move around differently relative to each other due to the changes in their respective KE and PE contents. Such changes in PE relative to KE result in density differences which cause different parcels of air to change their weights and rise or fall at different rates.
13) Thus does the atmospheric circulation reconfigure itself to remove the imbalance by adjusting the energy flows through different sections of the atmosphere both vertically and horizontally. The balance of UWIR and DWIR between surface ad top of atmosphere is restored at every level and the atmosphere is rescued.
14) Therefore, compositional changes have a zero net effect on temperature but the consequences are regional climate changes as the permanent climate zones change their sizes, intensities and positions relative to each other.
15) Finally, what would be the effect of human emissions as a proportion of changes that happen naturally?
16) On the basis of the facts set out in my three short articles it would be indistinguishable from zero.
Published by Stephen Wilde December 6, 2012