(Note: this originally published on Dr. Spencer’s blog on April 25th, and I asked if I could reproduce it here. While I know some readers might argue the finer points of some items in the list, I think it is important to keep sight of these. – Anthony)
by Roy W. Spencer, Ph. D.
There are some very good arguments for being skeptical of global warming predictions. But the proliferation of bad arguments is becoming almost dizzying.
I understand and appreciate that many of the things we think we know in science end up being wrong. I get that. But some of the alternative explanations I’m seeing border on the ludicrous.
So, here’s my Top 10 list of stupid skeptic arguments. I’m sure there are more, and maybe I missed a couple important ones. Oh well.
My obvious goal here is not to change minds that are already made up, which is impossible (by definition), but to reach 1,000+ (mostly nasty) comments in response to this post. So, help me out here!
1. THERE IS NO GREENHOUSE EFFECT. Despite the fact that downwelling IR from the sky can be measured, and amounts to a level (~300 W/m2) that can be scarcely be ignored; the neglect of which would totally screw up weather forecast model runs if it was not included; and would lead to VERY cold nights if it didn’t exist; and can be easily measured directly with a handheld IR thermometer pointed at the sky (because an IR thermometer measures the IR-induced temperature change of the surface of a thermopile, QED)… Please stop the “no greenhouse effect” stuff. It’s making us skeptics look bad. I’ve blogged on this numerous times…maybe start here.
2. THE GREENHOUSE EFFECT VIOLATES THE 2ND LAW OF THERMODYNAMICS. The second law can be stated in several ways, but one way is that the net flow of energy must be from higher temperature to lower temperature. This is not violated by the greenhouse effect. The apparent violation of the 2nd Law seems to be traced to the fact that all bodies emit IR radiation…including cooler bodies toward warmer bodies. But the NET flow of thermal radiation is still from the warmer body to the cooler body. Even if you don’t believe there is 2-way flow, and only 1-way flow…the rate of flow depends upon the temperature of both bodies, and changing the cooler body’s temperature will change the cooling rate (and thus the temperature) of the warmer body. So, yes, a cooler body can make a warm body even warmer still…as evidenced by putting your clothes on.
3. CO2 CANT CAUSE WARMING BECAUSE CO2 EMITS IR AS FAST AS IT ABSORBS. No. When a CO2 molecule absorbs an IR photon, the mean free path within the atmosphere is so short that the molecule gives up its energy to surrounding molecules before it can (on average) emit an IR photon in its temporarily excited state. See more here. Also important is the fact that the rate at which a CO2 molecule absorbs IR is mostly independent of temperature, but the rate at which it emits IR increases strongly with temperature. There is no requirement that a layer of air emits as much IR as it absorbs…in fact, in general, the the rates of IR emission and absorption are pretty far from equal.
4. CO2 COOLS, NOT WARMS, THE ATMOSPHERE. This one is a little more subtle because the net effect of greenhouse gases is to cool the upper atmosphere, and warm the lower atmosphere, compared to if no greenhouse gases were present. Since any IR absorber is also an IR emitter, a CO2 molecule can both cool and warm, because it both absorbs and emits IR photons.
5. ADDING CO2 TO THE ATMOSPHERE HAS NO EFFECT BECAUSE THE CO2 ABSORPTION BANDS ARE ALREADY 100% OPAQUE. First, no they are not, and that’s because of pressure broadening. Second, even if the atmosphere was 100% opaque, it doesn’t matter. Here’s why.
6. LOWER ATMOSPHERIC WARMTH IS DUE TO THE LAPSE RATE/ADIABATIC COMPRESSION. No, the lapse rate describes how the temperature of a parcel of air changes from adiabatic compression/expansion of air as it sinks/rises. So, it can explain how the temperature changes during convective overturning, but not what the absolute temperature is. Explaining absolute air temperature is an energy budget question. You cannot write a physics-based equation to obtain the average temperature at any altitude without using the energy budget. If adiabatic compression explains temperature, why is the atmospheric temperature at 100 mb is nearly the same as the temperature at 1 mb, despite 100x as much atmospheric pressure? More about all this here.
7. WARMING CAUSES CO2 TO RISE, NOT THE OTHER WAY AROUND The rate of rise in atmospheric CO2 is currently 2 ppm/yr, a rate which is 100 times as fast as any time in the 300,000 year Vostok ice core record. And we know our consumption of fossil fuels is emitting CO2 200 times as fast! So, where is the 100x as fast rise in today’s temperature causing this CO2 rise? C’mon people, think. But not to worry…CO2 is the elixir of life…let’s embrace more of it!
8. THE IPCC MODELS ARE FOR A FLAT EARTH I have no explanation where this little tidbit of misinformation comes from. Climate models address a spherical, rotating, Earth with a day-night (diurnal) cycle in solar illumination and atmospheric Coriolis force (due to both Earth curvature and rotation). Yes, you can do a global average of energy flows and show them in a flat-earth cartoon, like the Kiehl-Trenberth energy budget diagram which is a useful learning tool, but I hope most thinking people can distinguish between a handful of global-average average numbers in a conceptual diagram, and a full-blown 3D global climate model.
9. THERE IS NO SUCH THING AS A GLOBAL AVERAGE TEMPERATURE Really?! Is there an average temperature of your bathtub full of water? Or of a room in your house? Now, we might argue over how to do the averaging (Spatial? Mass-weighted?), but you can compute an average, and you can monitor it over time, and see if it changes. The exercise is only futile if your sampling isn’t good enough to realistically monitor changes over time. Just because we don’t know the average surface temperature of the Earth to better than, say 1 deg. C, doesn’t mean we can’t monitor changes in the average over time. We have never known exactly how many people are in the U.S., but we have useful estimates of how the number has increased in the last 50-100 years. Why is “temperature” so important? Because the thermal IR emission in response to temperature is what stabilizes the climate system….the hotter things get, the more energy is lost to outer space.
10. THE EARTH ISN’T A BLACK BODY. Well, duh. No one said it was. In the broadband IR, though, it’s close to a blackbody, with an average emissivity of around 0.95. But whether a climate model uses 0.95 or 1.0 for surface emissivity isn’t going to change the conclusions we make about the sensitivity of the climate system to increasing carbon dioxide.
I’m sure I could come up with a longer list than this, but these were the main issues that came to mind.
So why am I trying to stir up a hornets nest (again)? Because when skeptics embrace “science” that is worse that the IPCC’s science, we hurt our credibility.
NOTE: Because of the large number of negative comments this post will generate, please excuse me if I don’t respond to every one. Or even very many of them. But if I see a new point being made I haven’t addressed before, I’ll be more likely to respond.
Pretty much as I’ve always understood the science.
The closer we get to establishing a useful Global Average Temperature (i.e. satellites) and not the hilarious guesswork and manipulation that Warmist Scientists used in their reconstructions….the more likely we are to discover its remarkable stability.
This is why politically motivated science organisations relentlessly cool the past. They know that the runaway warming they predicted will not happen.
Ferdinand Engelbeen says:
May 1, 2014 at 2:29 pm
For the whole biosphere, we know the balance within large margins of error, thanks to the oxygen balance:
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We will have to agree to disagree on that one…..
Because I strongly disagree.
…unless those large margins of error are so large nothing can be derived from them
What would an oxygen balance show you….if most of the processes had nothing to do with oxygen?
Show us the empirical data proving that a ‘greenhouse effect’ caused by CO2 exists.
Sure. But you won’t understand it don’t want to believe it so you won’t bother to figure out why this is literally a photograph of the GHE at work:
http://wattsupwiththat.com/2011/03/10/visualizing-the-greenhouse-effect-emission-spectra/
The figures are all reproduced from Grant Petty’s book. Buy it. Study it. Then come back. Oh, and BTW, Roy pointed out that any idiot can take an IR thermometer and point it up and measure the GHE for themselves. But nobody ever does.
rgb
I think that a lot of the times when people end up making the kind of statements that you point out it is because they are using lax language and not bothering to be precise enough about what exactly they are speaking. For example, “There is no Green House Effect” is often written, but the writer usually means (and you can tell by the context) that “The man-made CO2 is not causing the temperature to rise significantly through the mechanism called the Greenhouse effect”.
Now they may be right or wrong about that, but unfortunately the long sentence gets shortened often to “there is no green house effect”. I do not think that there are any serious people who know what they are talking about who think that the mechanism, called the Greenhouse Effect, does not exist.
I think they are correct because we can see in the temperature data that the temperature has not risen for a couple of decades. So we can conclude that there is no “explanation” for why the temperature has increased, because it has not increased over that time-scale. They are trying to explain why something happened when it did not even happen. It is nonsense.
Now people might want to talk about longer timescales, and that is fine. But let’s not forget that this timescale was good enough for the Goose when the global temperature was rising in the short term, but suddenly when it is not rising, that timescale is not good enough for the Gandar!
Julien says:
markrust: Co2 is not a layer in the atmosphere, but the concentration of heavier gas decreases more rapidly as a function of altitude.
That’s right but what I would like to know is how thick it would be if it were.
IE IF the atmosphere WERE 100KM thick im guessing that it would be around 40 metres thick.?
“They are trying to explain why something happened when it did not even happen. It is nonsense.”
What they should be trying to explain is why, given that the green house effect does exist, has the temperature not risen significantly given that we have pumped all of this CO2 ito the atmosphere.
ie. people need to explain what has been observed, not what has not been observed.
Anthony: How come you don’t have threaded comments? There are a lot of threads on this page.
Not a criticism, I think this is a fantastic site and you do a great job in running it. I just wonder why you don’t have threaded comments.
Adam…they can’t explain something they don’t understand…
Well put BTW….
Neillusion says:
May 1, 2014 at 2:56 pm
N2 & O2 do absorb EM, but not in the visible & infrared parts of the spectrum.
Molecular nitrogen (N2) is largely transparent to IR & visible radiation because it’s a homonuclear molecule & thus has no dipole moment to couple to electromagnetic radiation at these wavelengths. Significant absorption does however occur at extreme ultraviolet wavelengths, beginning around 100 nanometers. This is associated with electronic transitions in the molecule to states in which charge is not distributed evenly between nitrogen atoms. This leads to significant absorption of ultraviolet radiation by nitrogen gas in earth’s upper atmosphere & those of other planets.
Oxygen (O2) presents two spectrophotometric absorption bands peaking at the wavelengths 687 & 760 nm, which is in the near IR (~700 nm to 1 mm) or visible range (variously given as roughly 400 to 700 nm, but broadly as 380 to 800 nm or narrowly 420 to 680 nm).
Sorry, meant N2 alone in the first sentence.
milodonharlani says:
May 1, 2014 at 1:36 pm
“So it’s the mass of the atmosphere that defines the greenhouse effect?”
I got snipped twice for mentioning that.
Lets examine #10, the Earth is not a black body. Nobody said indeed it was, but it’s the mainstay of the elementary quantitive greenhouse misinformation, the difference between earth’s blackbody temperature and the actual average “surface”-temperature. It’s not even close in a totally different setting. The problem here is not so much the emissivity but the conductivity. A theoretical black body is a perfect conductor, dividing thermal energy equally on its surface, whereas the Earth is a near perfect insolator. This makes the theoretical ‘black body temperature’ totally invalid.
Substantiation?, look at the moon, no atmosphere and no greenhouse effect and the average temperature or black body temperature? Well, Willis explained here http://wattsupwiththat.com/2012/01/08/the-moon-is-a-cold-mistress/ that the moon is much colder than you’d expect from the Stefan Boltzman equation. Therefore it’s useless misinformation to use the Earths blackbody model to explain greenhouse effect.
No the Earth is not a black body but it’s assumed on a daily basis in the first amendment paragraph 1, sub A of the holy global warming teaching to get the 33 degrees of greenhouse effect.
Mike Jonas:
You begin your post at May 1, 2014 at 2:50 pm saying
Sorry, but no.
Dr Spencer’s point 7 is correct but his explanation of it is plain wrong. There are several reasons for this. I point you to the Vostock ice core assertion which is an essential part of his explanation.
The ice takes years to seal from snow which accumulates on top of existing ice. The IPCC says it takes 83 years to seal and it is porous ‘fern’ until it seals. During those years air is pumped in and out of the fern by changes in atmospheric pressure (i.e. weather) which mixes the gas.
Hence, the very best temporal resolution of that data is 83 years. The effect of the ’83 years to seal’ is similar to an 83-year running mean conducted on annual data from ice which sealed in a year. This Vostock ice core data cannot be compared to the Mauna Loa data (i.e. the longest recent time series of atmospheric CO2 concentration) because the Mauna Loa measurements only started to be acquired in 1958 (i.e. less than 83 years ago).
Dr Spencer’s explanation is also supportive of the IPCC assertion that the atmospheric CO2 is an accumulation of excess anthropogenic CO2. That assertion is clearly not true.
This is the CO2 data from Mauna Loa
http://www.esrl.noaa.gov/gmd/ccgg/trends/
The seasonal variation in each year is a slow rise indicating increase to atmospheric CO2 followed by a steep fall as sequestration of CO2 is greater than CO2 emission followed by a rapid reversal. There is no reduction to the rate of sequestration as the sequestering ‘sinks’ fill. Clearly, the sinks do not fill.
The annual rise of any year is the residual of the seasonal variation of that year.
The dynamics of the seasonal change is consistent with the carbon cycle adjusting to a new equilibrium. Adjustment of mechanisms with long rate constants provides the annual rise while adjustment of the mechanisms with very short rate constants provides the seasonal variation.
Richard
THERE IS NO SUCH THING AS A GLOBAL AVERAGE TEMPERATURE
Better to say there is no such thing as an accurate global average temperature , the amount of data available and the problems it has means that if your actual doing science. as opposed to politics, you have to admit that all you can give is a ‘guess’ whose accuracy is questionable.
A problem which gets much worse the further back in time you get.
Its about , is what is really being said , but that does not bring in either confidence nor grant money .
I can monitor the temperature in my house to within ±5°F. Okay, in one room. Now, how can I accurately calculate the 500 or so houses nearest here with just that one thermometer (which is fixed to my wall)? Should I use spatial or mass weighting? Would it be accurate to ±0.01°C? What if I read my thermometer (still fixed to the wall of my house) 100 times a day? What if I installed a digital thermometer that took (& recorded) 1000 readings a second: how much more closely could I determine the temperature of the neighbours’s houses? ±0.0001°C? Better? Worse?
& more to the point: does the fact that it’s 80° in Texarkana have any effect at all on the temperature in Fiji? Please show your work, Mr. Global Average Temperature Guy.
richardscourtney says:
May 1, 2014 at 3:29 pm
There is no reduction to the rate of sequestration as the sequestering ‘sinks’ fill. Clearly, the sinks do not fill.
====
Thank you for saying that…………..so much better than I tried
Repost as I should of said 4 metres.
Julien says:
markrust: Co2 is not a layer in the atmosphere, but the concentration of heavier gas decreases more rapidly as a function of altitude.
That’s right but what I would like to know is how thick it would be if it were.
IE IF the atmosphere WERE 100KM thick im guessing that it would be around 4 metres thick.?
In case I wasn’t specific enough, in the “Calculating Line Spectra” paper from spectracalc above, equation 9 contains:
$
for some particular e.g. CO_2 line. 
at the moment. Note that this formula only effectively creates the fractional average contribution to the line widths given the pressure — it hides a lot of nonlinearity, because in both cases 
depend predominantly on the mean free time between collisions, which in turn depends on the temperature and the density (and, via the ideal gas law, the pressure). The mean free time between CO_2 on CO_2 collisions is an additional factor of 
longer than the time between CO_2 on anything else. Hence this formula is basically wrong. It only includes the direct effects of increasing the average linewidth by increasing the concentration of a fixed-absorptivity medium, but the average linewidth is also a function of its concentration. The partial pressure of CO_2 is so low that CO_2 on CO_2 collisions have a smaller effect on the total linewidth than doppler broadening, which is already ignored in this regime.
times some stuff that parameterizes the total Lorentzian line width
This means that I’m still waiting for somebody to explain why there is any significant variation to be expected in integrated absorptivity of CO_2 with variations in partial pressure as long as that partial pressure remains utterly negligible compared to the total pressure.
Note well that I am not in any way arguing that CO_2 is not opaque due to Beers-Lambert absorption — the mean free path of IR photons is without any doubt far, far less than the thickness of the atmosphere in the lower atmosphere, the integrated absorptivity in band is in no sense “negligible”. I just don’t see any argument for pressure broadening at a level that is conceivably detectable with same-species absorptivity being a weighted 0.04% contribution to the total Lorentzian per line, and with the same species line width dominated by an ADDITIONAL factor of 1/0.0004 = 2500 in the mean free time between same-species collisions.
I just cannot make a Fermi estimate come CLOSE to working out that this makes any contribution I should not completely, utterly ignore.
rgb
It looks like I have good company after all:
http://hockeyschtick.blogspot.co.uk/2014/05/maxwell-established-that-gravity.html
Au contraire, mon frere — A skeptic does himself or or his cause great harm when using bad arguments. Don’t you believe it’s important to get people to quit using false arguments when discussing why they are skeptical (to anything)?
I think you’re saying these top 10 fallacies don’t matter because global warming isn’t happening and it’s not important why, it’s just enough that the “consensus opinion” (my words) is wrong?
To be even clearer, equation 9 from Van Vleck and Weisskopf clearly shows that
where 
is the mean free time between collisions. None of the rest of the formula depends on the intermolecular force or species — Lorentzian phase interruption doesn’t really depend on the details of the force that causes the interruption as long as the interruption occurs in the impulse approximation (that is, time in contact is “short” compared to the line lifetime, which is without question going to be the case). Even allowing for second order exchange of virtual photons in resonance and so on, there is a factor of 0.0004 between the otherwise similar MFT in same and different species collisions.
Nothing I see in the theory seems likely to prove that same-species alpha contribution will be anywhere near as large as alpha between species once the double whammy of concentration squared is accounted for. One part in 10 to the seventh is anybody’s definition of negligible.
rgb
I’m confused. This is, by a wide margin, the largest group of skeptics on the Internet. While lurking, I cannot recall hearing any of the arguments 1-10 with the possible exception of item 9. Did I miss something?
Roy, Nice effort. 🙂 I’m amazed to see your persistence – I usually give up arguing with them after a day or two.
Here’s another one to add to your collection:
As everyone knows, the essential property that makes a ‘greenhouse gas’ is that it is opaque to IR, causing it to absorb and re-emit thermal IR in all directions. And as is easily confirmed in laboratory experiments, liquid water is opaque to thermal IR, absorbing it almost entirely within a few tens of microns. Therefore, liquid water should act as a greenhouse ‘gas’ (despite being liquid – you can call it a ‘greenhouse fluid’ if you like).
It’s a good test of whether somebody knows what they’re talking about to ask them to calculate the magnitude of the greenhouse effect in a shallow pond of water. The simplest way to do this is to split it up into thin horizontal layers each only just thick enough to be totally opaque. Each layer is at a particular temperature T, and emits blackbody radiation equally up and down into the layer immediately above and below. Sunlight enters the pond, and because water is pretty much transparent at visible wavelengths, the heat is absorbed at the bottom of the pond, from which it re-emits as thermal radiation. The topmost layer emits the same amount of energy upwards, partly by radiation, partly by evaporation. The layer immediately below it emits twice that amount, both up and down, since it is the only source of energy for the top layer, and the top layer must absorb from below the same amount it emits below and above. The layer below that emits three times the energy, for a similar reason, and so on. The power emitted increases linearly proportional to depth, it is the external energy flow multiplied by the number of layers down it is, and so the temperature increases with the fourth root of depth. If all the thermal energy is absorbed in 20 microns, or 1/500,000 metres, then there are 50,000 layers in a metre of water. The fourth root of 500,000 is about 15, which means the absolute temperature a metre down must be 15 times the temperature at the surface. If the surface temperature is 300 K, then the temperature at a metre depth must be just a little under 4500 K.
This warming of the lower layers of water is called the greenhouse effect, and it is why all the Earth’s oceans boil in the sunlight.
There can be no doubt that each and every layer of water must absorb and re-emit hundreds of Watts of thermal radiation back downwards, considerably more than you get from a clear sky. If each layer was only emitting 460 W then with 50,000 layers the total power emitted downwards by all the layers must be on the order of 23 MW. If the power increases linearly, it is 575 GW. This is how much backradiation there is in every cubic metre. So the bottom of a pond full of water has to be a bit warmer than if the water wasn’t there. But how much warmer? Can you work it out?
What essential physical property has the atmosphere got that water has not, that explains the correct result?
The best lesson to learn from such arguments, I think, is always not to be too sure of yourself. 🙂
Given Spencer’s post and many of the comments, there is a begged question that exists:
a) the begged question exists if one holds positions favoring all of Spencer’s 10 positions
b) and the begged question still exists if one holds positions favoring all 10 positions that Spencer maintains are incorrect skeptic positions
c) finally the begged question still exists if one holds any combination of a) or b) even when internal inconsistencies exist by mixing positions in a) or b)
The begged question is, Where are the unambiguously written down and corroborated comprehensive observations of climate which show anything more than a possibility of a small or hardly discernible unnaturalness in climate from geological times until today?
I see no reasonable evidence of anything other than small AGW by CO2, hardly discernible. So, Spencer’s article is excellent in its stimulation of discussion on important points of the science of the Earth-Atmosphere System (EAS), however, it begs that question.
John
rgbatduke says, May 1, 2014 at 3:18 pm:
“(…) this is literally a photograph of the GHE at work:
http://wattsupwiththat.com/2011/03/10/visualizing-the-greenhouse-effect-emission-spectra/“
So what gases are ultimately emitting earth’s IR to space, then, Robert? Since H2O and CO2 are apparently ‘unemitting’ it … Where does all the OLR out from the ToA, the 239 W/m^2, come from? FYI, the atmosphere absorbs [398-20-345.6=] 32.4 W/m^2 worth of radiative heat (you know about ‘heat’, don’t you Robert, that thing which actually ‘heats’ (raises the temperature of) something upon absorption) from the surface, but ultimately emits 219.7 W/m^2 worth of radiative heat to space (numbers from Stephens et al. 2012).