Nevertheless, it's always a good idea to check in more systematically to what is really out there. The search here will limit itself to Google searches which show up for the exact phrase "there is no greenhouse effect" and are within the past year. Alas (I keep giving away the surprise ending) it turns out that there really is no difficulty at all in finding sites which claim that there is no greenhouse effect. And, of course, are wrong in doing so. If someone were to demonstrate it and be correct, I'd have to be nominating them for major scientific medals. No such concern with these.
The arguments claiming to 'disprove' the greenhouse effect's existence seem to fall mainly in to 3 groups. I add the usual 'other' category since a philosopher friend has noted that all classification schemes wind up with one.
The first group, the 'linguistic argument' is the silliest. The problem with it is to mistake the words used to describe something with the thing itself. And then consider that if you can find a problem with the words, that there's nothing being described. Poof, it's gone. In this case, that if greenhouses don't operate by the 'greenhouse effect', that there is no greenhouse effect in the earth's atmosphere. I discuss it at more length in Greenhouse misnomer. The thing is, the words we use don't change the reality we're trying to deal with. The earth's atmosphere, due to water vapor, carbon dioxide, and some other rare gases, is fairly transparent to solar radiation and absorbs the earth's radiation pretty well. It's been suggested that we call it 'atmosphere effect' or 'Callendar effect' instead. They might be better names, but, regardless, whatever words you use, the fact of selective absorption of energy by the atmosphere remains.
The second argument also relies on giving words supremacy over the reality they're working to describe. One of the may verbal descriptions of the second law of thermodynamics is that 'heat doesn't spontaneously flow from a colder source to a warmer one'. But that's only a partial description -- as usual, the statement requires that you make some assumptions. Those assumptions aren't all true when considering the flow of energy by radiation in the atmosphere. In order to apply the second law properly, you have to sit down with the mathematics. If you don't want to, or can't apply the mathematics, at least remember that the first law of thermodynamics regards the conservation of energy, not 'heat'. Radiation carries energy, as does the motion of particles, the elevation of those particles (such as make up the atmosphere above ground), and other things. 'heat' refers only to temperature. The conservation of energy applies to all, and means that if radiation goes from here to there, there gets hotter (has more energy).
Venus supplies the third argument, which strikes me as bizarre, but, then, so does denying that there is a greenhouse effect. If you look at Venus, particularly at the surface, it is exceptionally hot. Far hotter than its blackbody temperature (about 224 K, colder than the earth's 255 K !) would suggest, and far hotter than Mercury -- which is closer to the sun and you'd expect to be hotter than Venus. The reason for that exceptional warmth is the extreme greenhouse Venus has due to its extremely heavy greenhouse atmosphere. It has about 90 times the surface pressure of the earth, and almost all of that is due to carbon dioxide, versus the Earth's about 0.04% Ok, that makes it apparent why someone who would want to deny that there's a greenhouse effect (or at least that CO2 isn't a greenhouse gas) would go to Venus.
The argument, however, is absurd. I haven't gone in to detail about this yet, but there's a concept called 'potential temperature'. This is the temperature that a blob of gas potentially has -- if you moved it in a plastic bag that perfectly insulated it against heat conduction or radiation but was fine with shrinking to fit your blob as you moved it from where it was to the surface. There is an old saying that 'hot air rises', which runs in to a bit of a problem with the fact that at 10 km elevation (the tropopause in mid-latitudes) the local temperature is far colder than the surface is. If hot air rises, why is that much higher air so cold? Because the potential temperature is so high for that air. If you lowered that blob to the surface, it would be much warmer than the surface air. Take a tropopause temperatures of, say, 225 K, versus surface temperature of 300 K. By the time you brought that blob down to the surface it would be 325 K -- it really is the hotter air.
The argument relies on a ... well, I don't know what to call it, but it isn't honest or accurate. The argument relies on taking the (observed) temperature at some large height and then bringing it down to the surface and saying that this potential temperature explains why the surface is hot. It's a falsehood, though, because it doesn't explain why that temperature isn't reached until the great (observed) elevation. If there were fewer greenhouse gases in the atmosphere, that elevation would be lower is the truth that is being ignored. It is the balance between incoming energy, albedo (reflection), and greenhouse effect which determines the temperature through the depth of the atmosphere.
- Claes Johnson
- Climate Clash
- Slaying the Sky Dragon (John O'Sullivan)
- Webcommentary (John O'Sullivan again)
- Climate Change Dispatch (O'Sullivan yet again, in yet another location; he also claims that a 33 C warming is 91.4 F, illustrating a certain lack of familiarity with at least one of the temperature scales and temperature change ).
- Principia-Scientific (and again)
- World-Mysteries (not O'Sullivan)
- Radical Green Watch (back to O'Sullivan)
Other / Multiple
- .pdf argument from Hans
- BMX Forum
- Icecap (Wednesday, August 3, 2011 -- scroll down)
The links show some overlap, citing each other or the same, somewhat older, sources. This takes us past the 20 links standard. Peruse them yourself, of course. That's rather the point. That, and the reference for future use that there are indeed people (and sites to publish them) who deny that there is such a thing as a greenhouse effect.
We also see that some of the same names are showing up. We've previously seen icecap and 'climaterealists' on the blog here as unreliable sources. More of the same. And several others up there, I've seen in my other looking around -- such as the oft-reprinted + rewritten John O'Sullivan. There's a certain persistence involved.
In doing this look-around, I also noticed the 'there is no greenhouse effect' argument getting unfriendly response from WUWT and Jo Nova's. Notice also that I'm quoting Fred Singer above, and Roy Spencer for one of the physics descriptions.