I want to applaud Joseph Postma and his latest blog post, spelling out his grievances against the “Greenhouse Apologists” and how they consistently manage to worm their way out of ever providing a definitive, coherent clarification of how the hypothetical “Radiative Greenhouse Effect” (RGHE, rGHE) is actually meant to work physically, brushing all sceptical objections to their vague – as it seems, deliberately equivocal – contentions aside by simply claiming that our differences are purely of a semantic nature. It doesn’t matter to them whether we describe one and the same process as “reducing cooling” or “increasing warming/heating”, because the end result – a higher temperature – will allegedly be the same either way, ignoring the simple fact that, in reality, these are two fully distinct (as in ‘opposite’) thermodynamic processes: 1) INSULATION, 2) HEATING. And so, conflating them, as if they were somehow basically the same process, causes confusion.
Unnecessary confusion. Scientifically pointless confusion.
Postma puts it very neatly and succinctly:
From Schroeder in “Thermal Physics”:
“Much of thermodynamics deals with three closely related concepts: temperature, energy, and heat. Much of students’ difficulty with thermodynamics comes from confusing these three concepts with each other.”
So right at the introductory level we have people on all sides who can neither define nor […] understand what energy, heat, and temperature actually are. I won’t define them for you right now but at least you have the textbook quote to cite that they are indeed not at all the same thing! This confusion about thermodynamic things is par for the course of climate alarmism, its bread and butter.
We’re discussing nature and the way its physics works, and it seems to me that nature doesn’t behave half one way plus another, but quite precisely according to physics and hence mathematics. There is nothing more precise than the behaviour of nature and mathematics and therefore there is nothing more important than their semantics. So, “purely arguing about semantics” is precisely what we’re supposed to do with physics, because this is what gives us understanding of anything about it in the first place.
In short: If we don’t go by the correct, agreed-upon term or definition for any specific physical phenomenon or process that we want to describe and explain, then this will ultimately prevent us from understanding what that physical phenomenon really is and how that physical process really works. We will end up confusing ourselves and/or the people we’re trying to communicate with.
What we say and write about things affects the way we THINK about them.
Most people actually walk around thinking the atmosphere directly warms/heats the surface, in the exact same way the Sun does. That the solar input can only warm it up to a point, and that the atmospheric input is specifically needed to warm it the final stretch, beyond the solar reach, so to say, up to the average temperature as observed. They simply do not get the fundamental distinction between how the Sun works and how the atmosphere works.
And this is simply because no one seems to bother making this distinction clear to them. Rather the opposite appears to be the case …
“Atmospheric back radiation” (LWdown) is consistently described by climate science as if it were an extra separate input of heat to the surface, right next to – and in addition to – the solar input. Everyone should know that it’s not. But climate science and the “Greenhouse Apologists” allow – no, they actively encourage – this profound confusion to prevail. Why? Does it simply come down to intellectual laziness, or is promoting and perpetuating such an endemic state of confusion a necessary thing, a ploy to prevent regular people from asking the wrong kinds of questions? This edifice is, after all, built entirely on pseudoscientific lines of argument …
A recent and apt example of the inanity of the “Greenhouse Apologists” and their absolute obsession with the confused idea of “sky radiation” somehow constituting extra heat to the ground, even without it actually being “heat” (we’re fine, because we don’t CALL it “heat” [Q], we just call it “energy” [E], thus avoiding any potential problems with the 2nd Law of Thermodynamics (which, after all, deals with “heat”, not “energy”), even though we expect our “energy flux” to produce a thermal effect exactly as if it were an actual “heat flux”, as per the 1st Law), is this gem from the well-known “Greenhouse Apologist” ‘The Science of Doom’ (SoD):
Picture the atmosphere over a long period of time (like a decade), and for the whole globe. If it hasn’t heated up or cooled down we know that the energy in must equal energy out (or if it has only done so only marginally then energy in is almost equal to energy out). This is the first law of thermodynamics – energy is conserved.
What energy comes into the atmosphere?
- Solar radiation is partly absorbed by the atmosphere (most is transmitted through and heats the surface of the earth)
- Radiation emitted from the earth’s surface (we’ll call this terrestrial radiation) is mostly absorbed by the atmosphere (some is transmitted straight through to space)
- Warm air is convected up from the surface
- Heat stored in evaporated water vapor (latent heat) is convected up from the surface and the water vapor condenses out, releasing heat into the atmosphere when this happens
How does the atmosphere lose energy?
- It radiates downwards to the surface
- It radiates out to space
..end of digression
This is simply too stupid to be real. And yet he still said it. And I’m sure he meant it. I’ll bet he can’t see the problem himself. SoD is clearly one of those confused specimens incapable of distinguishing between “energy” [E] and “heat” [Q]. He thinks he knows the distinction, oh, yes he does, he’s been telling us for a long time. But he really doesn’t. And here he – once again – shows us just how he doesn’t …
Thermodynamics 101: The atmosphere does not lose energy by radiating downwards to the surface. This would only happen if the surface were colder than the atmosphere. Or in a hypothetical situation where the surface is warmer, but still somehow doesn’t radiate to the atmosphere at the same time as the atmosphere radiates to it.
The atmosphere – on average – only loses energy by radiating to SPACE. It cannot lose energy in any other direction. Because all regions surrounding the atmosphere other than space are – on average – at a higher temperature than the atmosphere. And so the atmosphere will always only gain energy from its thermal interaction with these other regions.
A loss of energy from a thermodynamic system is when, between t0 and t1, its U has decreased, normally associated with an absolute drop in the system’s temperature T (never with a rise). Likewise, a gain of energy to a thermodynamic system is when, between t0 and t1, its U has increased, normally associated with an absolute rise in the system’s temperature T (never with a drop). Yes, that system can indeed lose and gain energy at the same time, and there will be a net loss or a net gain of (internal) energy [U] and a corresponding drop or fall in temperature [T] as a result. But such a simultaneous loss and gain of energy from/to a thermodynamic system resulting in a net change in its U (and T) are – by thermodynamic definition – never part of the same heat transfer. The system can only lose OR gain energy inside ONE specific thermal interaction.
Case in point: The surface of the Earth takes part in TWO heat transfers at the same time: 1) Sun → Sfc, and 2) Sfc → Atm/Space. It always gains energy from the first transfer (its Qin (heat input)), just as it always loses energy through the second (its Qout (heat output)). There is never any gain in energy for the surface, no rise in its U (and thus no rise in its T), resulting from the second transfer specifically, from the average thermal interaction between the surface and the atmosphere/space. The Sun is its “hot reservoir” (heat source) and the atmosphere/space are its “cold reservoir” (heat sink).
Net heat [Qnet] is simply Qin minus Qout. For the Earth, the net heat is close to zero. That is not to say that the heat input from the Sun or the heat output from the Earth are themselves anywhere close to zero. It simply means that they are more or less inversely equal. They balance …
You cannot and should not describe the physical process of “insulation” as an equivalent to – and in terms of – the physical process of “heating”. And so you can’t treat the “atmospheric back radiation” as an ADDITION of energy to the surface, as a separate input equal to the solar one. That would simply be un-physical. You have to treat it only as a reduction of the OUTGOING energy flux, of the surface heat loss:
Figure 1. The surface radiative budget does NOT look like this: IN, 188+345 = +533 W/m2; OUT, -23+(-398) = -421 W/m2. Only “Climate Science” would propose such ridiculousness. It looks rather like this: IN, 188–23 = +165 W/m2; OUT, 345–398 = -53 W/m2. The +165 W/m2 is the Sfc Qin(sw), the -53 W/m2 is the Sfc Qout(lw), the Sfc Qnet(rad) = 165–53 = +112 W/m2. Two separate heat transfers.