Why atmospheric MASS, not radiation? Part 2

Be sure to read Part 1 first, now …


How is the rGHE defined in the most basic way? If you have a planet with a massive atmosphere, the strength of its “greenhouse effect” is defined as the difference between its apparent planetary temperature in space and the physical mean global temperature of its actual, solid surface. The planet’s apparent temperature in space is derived simply from its average radiant flux to space, not from any real measured temperature. It is assumed that the planet is in relative radiative equilibrium with its sun, so is – over a certain cycle – radiating out the same total amount of energy as it absorbs.

If we apply this definition to Venus, we find that the strength of its rGHE is [737-232=] 505 K. Earth’s is [288-255=] 33 K.

The averaged planetary flux to space is conceptually seen as originating from a hypothetical blackbody “surface” or ‘radiating level’ somewhere inside the planetary system, tied specifically to a calculated emission temperature. This level can be viewed as the ‘average depth of upward radiation’ or the ‘apparent emitting surface’ of the planet as seen from space. Normally it is termed the ERL (‘effective radiating level’) or EEH (‘effective emission height’).

The idea behind the ERL is very simple, but does it accord with reality? The apparent planetary temperature of Venus in space is 231-232K, based on its average radiant flux, 163 W/m2. Likewise, Earth’s apparent planetary temperature in space is 255K, from its mean flux of 239 W/m2. In both of these cases, the planetary output is assumed to match its input (from the Sun), so one ‘easy’ method one could use to derive the apparent temperature of a planet is by simply taking the TSI (“solar constant”) at the planet’s (or moon’s) particular distance from the Sun, and multiply it with 1 – α, its estimated global (Bond) albedo, a number that’s always <1, finally dividing by 4 to cover the whole spherical surface. Determining the average global albedo is clearly the main challenge when going by this method. The most common value provided for Venus is 0.75, for Earth 0.296.

But does the resulting value really say anything about the actual planetary temperature? If the planet absorbs a mean radiant flux (net SW) below its ToA, then how this flux affects the overall system temperature very much depends on the system’s total bulk heat capacity. If it is large, the flux will have little effect, if it’s small, the flux will have a bigger effect.

Continue reading

Why atmospheric MASS, not radiation? Part 1

And so finally we have reached the stage where we will explain why the atmospheric insulating effect is inherently a ‘massive’ one and not a ‘radiative’ one. The answer is quite intriguing, maybe even a bit surprising to some, the solution rather subtle in many respects. I have settled for two posts, but could probably have written several, considering the bewildering amount of different aspects in some way or other pertaining to this whole issue.

I hope you can bear with me on what might seem like a rather repetitive style of writing in this first post. I have only done so in a humble attempt to punch through the basic idea presented, which might at first come off as a novel or unfamiliar one to most people.

The second post is more lengthy, gradually winding its way towards the final resolution. When reading it, always bear this first one in mind.

I will most likely at some point publish a (strongly) condensed version of these posts. However, their content and interconnected nature might take time to digest.

OK. Let’s begin …


In his ‘Physics Today’ feature article of January 2011, “Infrared radiation and planetary temperature”, Raymond T. Pierrehumbert stated the following about the proposed rGHE surface warming mechanism:

An atmospheric greenhouse gas enables a planet to radiate at a temperature lower than the ground’s, if there is cold air aloft. It therefore causes the surface temperature in balance with a given amount of absorbed solar radiation to be higher than would be the case if the atmosphere were transparent to IR. Adding more greenhouse gas to the atmosphere makes higher, more tenuous, formerly transparent portions of the atmosphere opaque to IR and thus increases the difference between the ground temperature and the radiating temperature. The result, once the system comes into equilibrium, is surface warming.”

This is a most interesting quote, one that reveals a central misconception lying at the heart of the rGHE and AGW hypotheses. In order to get his message across, Pierrehumbert employs two quite specific terms – “enable” and “cause” – as if they were almost interchangeable. They are not. Read the two highlighted sentences once more. “An atmospheric ‘GHG’ enables a planet to radiate at a temperature lower than the ground’s, if there is cold air aloft. It therefore causes the surface temperature to be higher than would be the case if the atmosphere were transparent to IR.”

How did he get from “enables” to “therefore causes”?

He seems to forget that there’s crucially a third term that needs to be included before this chain is complete and one is able to see the whole picture, and that term is “necessitate”.

Something necessitates an effect, but cannot cause the effect before it is enabled to do so.

I will explain … Continue reading

‘To heat a planetary surface’ for dummies; Part 5b

If there were no atmosphere on top of our solar-heated terrestrial surface, then Earth’s mean global surface temperature would likely be about 80 degrees lower than what it actually is (209 rather than 289K). And this would be in spite of the fact that in this case the solar heat input to the global surface would be almost 80% larger on average (296 rather than 165 W/m2).

Much of this cooling of the mean would simply come as a result of greatly amplified temperature swings between day and night and between the seasons. The larger the planetary surface temperature amplitudes in space and time, the lower the mean global planetary surface temperature needs to be to maintain dynamic radiative equilibrium with the Sun. This is why the Moon is so cold.

So we need to get this straight: The Earth’s surface would be a much colder place without an atmosphere on top of it. Even with much more solar heat absorbed. There is no escaping this. The lunar surface is about 90K colder than ours, on average.


The short answer: It insulates the solar-heated surface.

Well, so how does it do this?

Mainly in four ways, three of which concern suppressing the effectiveness of convective cooling of the surface at a certain temperature.

Why is this important? Why convective cooling?

Consider a hypothetical single-room house. Continue reading

‘To heat a planetary surface’ for dummies; Part 5a

In 1938, English steam technologist Guy Stewart Callendar wrote what proved to be a seminal – one might even venture to call it the foundational – paper of the entire modern AGW pipe dream movement, with its rather determined effort at postulating what we today call the “Radiative (Atmospheric) Greenhouse Effect” (rGHE), or as some people would prefer it: the “Callendar Effect”.

In his paper – “The Artificial Production of Carbon Dioxide and Its Influence on Temperature” – Callendar argued that the increase in global atmospheric CO2  concentration due to our industrial endeavours would (and did) warm the world because of the alleged augmenting influence of this IR-active molecule on the so-called “sky radiation” (what we today call “(atmospheric) downwelling longwave radiation” (DLR, DWLWIR), more commonly known simply as “back radiation”):

“Few of those familiar with the natural heat exchanges of the atmosphere, which go into the making of our climates and weather, would be prepared to admit that the activities of man could have any influence upon phenomena of so vast a scale.

In the following paper I hope to show that such influence is not only possible, but is actually occurring at the present time.”

Notice here how Callendar was well aware that with his hypothesis, he was challenging a generally accepted scientific paradigm of his time, one which held that our climate and weather are natural phenomena with purely natural drivers, which can not in any meaningful way be influenced (globally, at least) by human activity.

Callendar claimed that it can. And that it does. He even went so far as to claim he could show it …

Well, then; by all means bring it on! To quote Carl Sagan:

“Extraordinary claims require extraordinary evidence.”

Continue reading

UAH need to adjust their tlt product

Update (March 9th) – Dr. Roy Spencer just gave an interesting response:

“yes, we have been aware of some spurious warming over land versus over the ocean after approximately 2000. Our version 6 dataset (now close to completion) will have most of that removed, although it looks like some of it is genuine.”

I guess we all just have to wait and see …

I have earlier noted a rather curious blocklike shift up in the UAH tlt (lower troposphere temperature) timeseries occurring abruptly some time in 2005. (There is most likely a similar – only downward – step at the same time in the RSS tlt timeseries; however, this post will not address this one.)

The 2005 shift seems very much to originate in the land portion of the UAH dataset. The shift can readily be seen here, but not at all in the oceanic portion, a situation which is quite unprecedented in the record – global land temps simply do not by any known natural mechanism all of a sudden jump out of step with the global ocean temps and then remain elevated high above thereafter:

Land vs. ocean, UAH

Figure 1. As you can see, something quite out of the ordinary happens in the UAH land curve in 2005. Continue reading

The “enhanced” greenhouse effect that wasn’t

Update (March 24th) at the end of this post – a kind of a response from Feldman.

There was much ado recently about a new paper published in ‘Nature’ (“Observational determination of surface radiative forcing by CO2 from 2000 to 2010″ by Feldman et al.) claiming to have observed a strengthening in CO2-specific “surface radiative forcing” at two sites in North America going from 2000 to the end of 2010 (a period of 11 years) of about 0.2 W/m2 per decade, and through this observation further claiming how they have shown empirically (allegedly for the first time outside the laboratory) how the rise in atmospheric CO2 concentration directly and positively affects the surface energy balance, by adding more and more energy to it as “back radiation” (“downwelling longwave (infrared) radiation” (DWLWIR)), thus – by implication – leading to surface warming.

In other words, Feldman et al. claim to have obtained direct empirical evidence – from the field – of a strengthening of the “greenhouse effect”, a result, it would seem, lending considerable support to the hypothesis that our industrial emissions of CO2 and other similar gaseous substances to the atmosphere has enhanced, and is indeed enhancing still, the Earth’s atmospheric rGHE, thus causing a warming global surface – the AGW proposition.

From the abstract:

(…) we present observationally based evidence of clear-sky CO2 surface radiative forcing that is directly attributable to the increase, between 2000 and 2010, of 22 parts per million atmospheric CO2.”


“These results confirm theoretical predictions of the atmospheric greenhouse effect due to anthropogenic emissions, and provide empirical evidence of how rising CO2 levels (…) are affecting the surface energy balance.”

So the question is: Do these results really “confirm theoretical predictions of the atmospheric greenhouse effect due to anthropogenic emissions”?

Of course they don’t. As usual, the warmists refuse to look at the whole picture, insisting rather on staying inside the tightly confined space of their own little bubble model world. Continue reading

‘To heat a planetary surface’ for dummies; Part 4

I rounded off Part 3 of this series by suggesting the following:

Next up: How do you heat a planetary surface, then? If not by the Earth’s own thermal radiation, a result of its temperature rather than a cause of it … How does the atmosphere insulate the surface?”

Not so. This will have to wait a bit still. Next post, perhaps. I will rather try to clarify my stance on the whole ‘bidirectional flow’ concept thing, seeing how this topic has a tendency of stirring up both emotions and misconceptions.

There is quite a bit of confusion surrounding the whole issue of electromagnetic radiation, the Stefan-Boltzmann Law and the thermodynamic concept of ‘energy transfer’.

I will try to explain why there can be no such thing as a bidirectional energy transfer between two objects radiating at each other. Yes, they are radiating at each other! Radiation goes in all directions. Continue reading