Monday, July 23, 2012

There is no greenhouse effect

Quote-miners will love that subject line, and it isn't a statement of my belief.  But it's been recurring some that there are people denying that anybody believes that there is no greenhouse effect.  Yet, typically on the same day as that claim, I keep seeing people deny that there is a greenhouse effect.  It's also common enough that Fred Singer, who probably would label me as a 'warmist', has made his own complaints about people denying that there is a greenhouse effect.

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.


Linguistic argument
Second Law Argument
Venus is warm because of surface pressure / lapse rate, not a greenhouse effect

Other / Multiple

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.

7 comments:

EliRabett said...

Hi Bob, you left out some of Eli's favorites Gerlich and friend with defender Kramm and, how can one forget Chilingar and the Russian Academy of Sciences at USC.

You got a sheltered life there.

Robert Grumbine said...

I run for shelter on a regular basis. But not so much this time -- Gerlich was more than a year ago. I arbitrarily limited myself to things within the year.

But by all means, bring in some links to your favorites. And, say, your response to Gerlich and (?Tschuessner).

Anonymous said...

Meta comment:have you lost interest in the math climatology site at penguindreams ? i would rather read that than endless refutation of lies.

sidd

Neven said...

Bob, sorry for bumping in like this. I'm sure you're aware of what is going on in the Arctic.

I have a question:

If possible, JAXA needs to get AMSR2 online as soon as possible. We need the best sensor to assess this situation. Is that too fast for the calibration and validation process? Do you think they'll get it online before the minimum? Would they even want to do that?

Robert Grumbine said...

The plan at JAXA is for ice concentrations to be operationally computed and distributed in May 2013, one year post-launch. I hope that it happens faster, but the documented plan makes sense as a conservative approach towards full operational status.

It may not be important for the Japanese, but the crowd documented in this post and some coming ones argues in favor of not making preliminary information available. One problem being that if you find an improved method later, they point to it as conspiracy to hide the 'truth', or as 'proof' that scientists know nothing. As opposed to seeing the reality that science is always about finding a better answer. A second, which hit the NCDC sea sueface temperature folks, is that you may never be able to use improved methods. For NCDC, they have to continue using pre-satellite methods for their work ranking which years are warmest. Using the satellite data changes the ordering slightly, and the conspiracy theorists pitched a ferocious fit. Can't go about using the most and best data in the best ways we can.

As far as I know, that sort of consideration doesn't apply much in Japan. The society seems to deal more straightforwardly with science. It seems to be just a general conservatism (in the old sense of the word, not the current US politics sense) of approach to doing science.

Not that this stops me from hoping that I can get the rawer data sooner and make some use of it (perhaps as part of a blended product, so it isn't in competition with JAXA's own sea ice fields when they come out?). But I wouldn't hold you breath for an early September release or pre-release. I'm sure, though that when it does become operational, the data will be reprocessed as far back as possible. My guess (no special information, just it is how people in this area think) is that it will cover back to September 2012. The data are flowing and being saved. It is just a matter of working out the best calibration and algorithm fine-tuning.

Neven said...

Thanks a lot for the comprehensive answer, Bob.

dbostrom said...

The "second law is sacrosanct" folks blow my mind. What is so difficult about energy loss rate temporarily being reduced by interposing some mechanism returning energy to the lossy object, until the thing losing energy becomes energetic enough to overcome the impediment to loss and reach a new equilibrium?

"Loss rate temporarily reduced." Surely it's not so challenging?

Though the specific mechanisms are different, there's a simple example of this process that also should not work according to those suffering from second law pathology. Many spacecraft maintain thermal stability around desirable operating temperatures for components in part by employing reflective louvers controlled by a simple bimetallic spring, thus governing exposure of the spacecraft interior to the infinite sink of space according to the interior temperature. The spacecraft thus is able to radiate more or less energy depending on the exposure of the interior. According to the second law neurotics this is impossible because the spacecraft interior temperature should have nothing to do with the louver positioning, but it seems spacecraft disagree with this notion.

Imagine reaching into such a spacecraft and giving a louver bimetallic a nice, tight fold and crimp with a pair of pliers. Would the interior of the spacecraft stay the same, or would it increase until the increased tension of the spring was overcome?

For the true geek or in case you're building your own spacecraft, a manufacturer's brochure on bimetallic louvers: Thermal Control Louvers