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This is a book that purports to discredit the hypothesis of man-made global warming due to carbon dioxide produced by the burning of fossil fuels. However, it contains much of what I would term "crackpot science" and so the book cannot be taken seriously. Worse than that, it is seriously misleading if used as a source of scientific information. Finally, it enables CAGW believers to say "Deniers are talking nonsense as usual".
My own position
My review of "Slaying the Sky Dragon - Death of the Greenhouse Gas Theory" is not complimentary so, for the avoidance of doubt, let me make my own position clear:
- I think that belief in catastrophic man-made climate change is akin to a religion which has many passionate believers, whose belief is based on faith rather than evidence.
- I think that the global warming mass delusion has resulted in immense harm in numerous ways.
- The evidence for global warming was based on analysis of temperature data with numerous problems of reliability but in any case the data has failed to show continued global warming for the past ten years or so.
- The evidence for CO2 being a threat is non-existent. The only "evidence" is computer models, which have been programmed by people with a strong desire to produce evidence for a strong relation between CO2 and global temperatures. But, as someone said, a computer model is an illustration of a hypothesis, it is not evidence.
I am sure that, at some time in the future, perhaps not in my lifetime, the whole thing will be recognized as the greatest mass-delusion of all time. However, there are now so many people and organizations who benefit from it, not to forget a generation of indoctrinated school children, that I don't think this will happen soon.
Let me make clear my understanding of thermal radiation, because the explanations in the book differ very greatly from radiation physics as taught in normal texts. Here is how it is normally understood:
- A black body absorbs all radiation that impinges on it, irrespective of the temperature of the black body or the wavelength of the radiation. Equivalently, every photon impacting a black body is absorbed by it, irrespective of the energy of the photon or the temperature of the body that emitted the photon. The temperature of the black body absorbing the photon is irrelevant to anything - it absorbs all photons whatever its temperature.
- A spherical black body emits radiation whose total power is determined solely by its surface area and its absolute temperature, the radiated power being proportional to the fourth power of the absolute temperature. The spectrum of its radiation is described by the Planck's law formula.
The book has numerous explanations of radiation that disagree totally with what I have written above.
Nine chapters, covering about 50 pages, are by Alan Siddons generally dealing with radiation, greenhouse effect and claiming to expose misconceptions of physics that are to be found in climate science.
There are two chapters by Tim Ball "Analysis of Climate Alarmism" parts one and two which reviews how climate research became politicized and how the IPCC came into existence as an organization whose mission was to convince governments that they needed to introduce policies based on the danger of man-made global warming. I found these chapters interesting and informative.
There are ten more chapters, by six other authors, including two by Claes Johnson, entitled "Climate Thermodynamics" and "Computational Black Body Radiation".
The book contains numerous misconceptions of physics. To correct or explain all of them would need a document almost as long as the book itself. I will focus on two examples from two chapters. However note that misconceptions abound throughout the book - it is not simply a matter of just one or two errors here and there.
"Examining Greenhouse Theory" by Alan Siddons.
This chapter starts with a diagram from a Washington University course. Many readers of this review will be familiar with similar diagrams showing:
- 342 W/m^2 arriving as solar radiation
- 102.6 W/m^2 being reflected to space immediately
- 239.4 W/m^2 continuing downwards and then warming the earth (taken to be 240 W/m^2 in the text)
The earth then re-radiates 240 W/m^2, as it is in thermal equilibrium.
It is assumed that the 240 W/m^2 radiation leaving the earth is absorbed by an atmospheric layer and re-radiated 50% upward and 50% downward, so that 120 W/m^2 goes to space and 120 W/m^2 goes back to earth, where it is absorbed and the 120 W/m^2 is then re-radiated.
I see no problem with this. Of the 120 W/m^2 re-radiated by the earth, 60 W/m^2 returns again, then 30 W/m^2, and so on. So we have going spaceward 120 + 60 + 30 +... = 240 W/m^2. This is the same as originally arrived at the surface, so things are in equilibrium, with as much power being radiated spaceward as originally arrived at the surface directly from the sun.
Nothing wrong with that that I can see. The earth's temperature is being maintained but it is not receiving any additional heat from anywhere - including the cooler greenhouse gases above its surface so there is no need to argue that cold objects do not heat hotter objects.
Yet Alan Siddons immediately says "If people are gullible enough to believe such a scenario, and apparently millions do, they deserve what's coming down the road at them."
Then he says "Substitute an infrared filter for that layer of 'greenhouse gases.' Direct a radiant heater at an infrared filter, then. (sic) According to greenhouse physics you will now have the equivalent of two radiant heaters. (...) Two heaters for the price of one. But no, that's not all. Remember that the radiant heater will be heated by its own re-directed energy (...) It's not only a perpetual motion machine - it accelerates to boot!"
This is a fallacious argument. The earth is not equivalent to a radiant heater generating its own heat and radiating it. The greenhouse gasses are not equivalent to an infrared filter.
Other chapters by Alan Siddons contain many misconceptions. Most can be translated as equivalent to a belief that photons emitted by cool body cannot be absorbed by a warmer body.
"Computational Blackbody Radiation" by Claes Johnson
At a quick glance, this chapter seems to be a detailed discussion of radiation physics from a mathematical viewpoint, with plenty of mathematics - no shortage of integral signs and formulas. But looked at in any detail, it is simply nonsense - scientific sounding nonsense but still nonsense.
In section 1.1 he says "The purpose of this note is to show that particle statistics can be replaced by deterministic finite precision computational wave mechanics. We thus seek to open a door to restoring rational physics including climate physics, without any contradictory wave-particle duality".
Immediately my alarm bells started sounding. Anyone who announces that he will replace the physics of the twentieth century with a new alternative immediately runs the risk of being thought to harbor delusions of grandeur. "...contradictory wave-particle duality." Sounds impressive but does it mean anything? I don't think so.
He says "A blackbody thus can be seen as a system of resonators with different eigen-frequencies which are excited by incoming radiation and then emit radiation. An ideal blackbody absorbs all incoming radiation and re-emits all absorbed radiation below cut-off"
This is simply rubbish. See my note above as to what a black body actually does.
"As a transformer of radiation a blackbody thus acts in a very simple way: it absorbs all radiation, emits absorbed frequencies below cutoff, and uses absorbed frequencies above cut-off to increase its temperature. A blackbody thus acts as a semi-conductor transmitting only frequencies below cut-off, and grinding coherent frequencies above cut-off into heat in the form of incoherent high-frequency noise."
"We here distinguish between coherent organized electromagnetic waves of different frequencies in the form of radiation or light, and incoherent high-frequency vibrations or noise, perceived as heat."
This all sounds impressive but it is simply gibberish. It is nonsense. A black body acts as a semi-conductor? Does he know what a semi-conductor is?
A blackbody grinds coherent frequencies above cut-off into heat? This is meaningless waffle. As I said, see above for my note of what a black body actually does.
I've taken just two snippets from two chapters. It's too bad that the book is filled with scientific nonsense like this, as there is plenty of global warming pseudo-science that needs to be debunked.
But you cannot debunk global warming pseudo-science with gobbledegook science. Worse, it enables The Faithful to say "There you are, you see? Deniers talk nonsense".