(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.
A helpful process of debate would not be to refer to them as “Top 10 list of stupid skeptic arguments”
#9 “Is there an average temperature of your bathtub full of water? Or of a room in your house?”
I agree with others that this could do with a lot more explanation. You might be able to calculate an average temperature for a room, or a bathtub, but what about a bathroom, when the tub is filled with water? And how meaningful is the “average temperature” when a hot dry room would be affected by the introduction of water, which would absorb energy by becoming water vapour, thereby reducing average temperature?
Is it meaningful to average temperatures that have totally different energy contents? For example, sub-freezing air will be much drier, and so have much less energy. Can we just average that with other temperatures?
That is to say nothing about the issues of measurement precision, accuracy and comparability, especially when the records are adjusted, including over many decades.
What we are entitled to say about CO2 is “We think that CO2 has a warming effect but we do not know how big or how small”
We are not entitled to say that CO2 causes warming; the last 17 years proves that beyond doubt.
“There is an unknown quantity of factors that affect temperature, we do not even know what they all are but we think CO2 would tend to be a warming factor”.
A minor point on item 2, the 2nd law of thermodynamics deals with entropy and reversibility. The 0th law of thermodynamics says heat always flows from a higher temperature to a lower temperature. Overall I like the paper it makes some good points.
Stephen Rasey says:
May 1, 2014 at 7:19 am
“@Thomas Hogg at 6:17 am
Could Dr Spencer complement this valuable article with its analogue
ie Ten Skeptical Arguments that do hold water?
Absolutely necessary and should immediately follow this post.”
I agree with Stephan and Thomas. I have never used any of these 10 arguments (thankfully), but what are the top 10 best skeptical arguments??
I never read the Skeptics Handbook, but maybe Jo Nova could help on this. I really like her 50 to 1 YouTube interview – there are 4 major points that the warmists cannot answer…
@The other Phil
We all know that 400 ppm of CO2 is different than 400 ppm arsenic. This is a poor analogy.
Regarding #5; This is the “CO2 logarithmic’ argument, yes? However, does the pressure broadening effect have any meaningful effect for a trace gas in Earth’s atmosphere? Perhaps if we had CO2 as 10, 20, or 30% of the atmosphere the pressure broadening effect would be meaningful … but would it not be correct to say that “in the context of the amount of CO2 in our atmosphere, the effect of adding more CO2 to the atmosphere is essentially zero since at the current pressure, the absorption bands are saturated.”? Just wondering….
[SNIP – DO NOT ASSUME YOU KNOW WHAT WE (ROY AND I) THINK OR KNOW. I DO NOT LIKE HAVING WORDS PUT IN MY MOUTH – ANTHONY]
Dr Spencer,
Wonderful post.
However, I haven’t heard some of these “arguments” until today and have been unsuccessful in finding articles, posts, or youtube clips for a couple of the items on your list. To put the “melting icing on the cake” would be if the title of each argument was a link to an example of that argument being used in context.
Resourceguy @ur momisugly here,
Read through the thread. Points 4, 7 and 9 are being contested by plenty of people. This is because those views are proliferated in the climate blogs articles and comments sections.
Eg, a few posts upthread of yours,
Transposing the ice age lead/lag relationship between temperature/CO2 onto the modern age is an extremely prolific trope in the climate blogosphere. I’m genuinely surprised you are not aware of it.
For those “clobbering” number 7, yes, ocean outgassing of CO2 lagged warming transitions from glacial periods in the geologic records. But that is not what is happening now. The evidence is conclusive. Simple arithmetic is all it takes. Human industry has emitted twice as much as the increase in atmospheric concentrations. It can’t be coming from the oceans, because CO2 in the oceans has been increasing at the same time. Oceans are absorbing about half of the CO2 human industry has omitted. These are not the only evidence, by a long shot, but they are hard to refute. Where is all the anthro CO2 going? And how is the system squirreling it away while pumping out the supposedly natural CO2?
This is an argument that sincere critics definitely need to let go of.
“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.”
The surface temperature measurement with thermometers is therefore futile. (violates Shannon’s theorem)
I’m a little confused by #5.
“THE CO2 ABSORPTION BANDS ARE ALREADY 100% OPAQUE. First, no they are not,”
Makes it sound like absorption bands come in shades of gray. Would it be more accurate to say slayers believe absorption in the CO2 wavelengths is already 100% complete?
“and that’s because of pressure broadening.”
Does a higher percentage of CO2 make the air more dense?
“Second, even if the atmosphere was 100% opaque, it doesn’t matter.”
The slayers don’t say the atmosphere is opaque. Maybe some CAGWs do.
The article has inspired some excellent questions, even if they seem basic. Like how climate is defined, or how the greenhouse effect is defined. Good critical analysis returns to the basics as understanding evolves, to clarify issues, or to see if the basics require modification. A warmist could not have inspired this kind of genuine inquiry, and I remain admiring of Spencer’s article for promoting such investigation.
#9 – Of course there’s a calculable average global temperature. How useful that is to establishing past long term trends in the face of inconsistent instrument records, comparative proxies and varying grids is a a very real question.
I actually have a couple of questions generated from the list above — serious ones I hope.
First, pressure broadening. Yes, I understand exactly where pressure broadening comes from — it is associated with the phase interruption brought about by collisions that alter the shape/width of the IIRC Lorentzian associated with any given emission line. The collisions don’t add energy (on average) but the phase interruption ensures that the fourier transform of the emission line gets fatter. No problem.
My problem is that I cannot for the life of me understand why pressure broadening should depend in any way on the partial pressure of CO_2. It should depend on the pressure, to be sure, and the density, without any doubt and the temperature — basically on the mean free time between collisions. Collisions with anything, not just CO_2 – CO_2 collisions.
Now is somebody asserting the increasing atmospheric CO_2 from 300 ppm to 600 ppm is going to increase the absolute pressure of the atmosphere anywhere in any measurable way? Or am I very confused about pressure broadening and does it in fact depend on partial pressure of particular species? Because this is one thing I just don’t get…
A second nit to pick might be the discussion of global average temperature. The problem isn’t that one cannot define a global average temperature — the problem is that global average temperature is a poor, and enormously variable, metric for energy balance. Temperature is useful in e.g. 1st law discussions as it represents internal energy via the equipartion theorem (or more sophisticated stat mech sums). It isn’t a perfect tool even there, as one has various constraints on any “system” that one wishes to assign a temperature (as it is already an average quantity!). One requires some sort of coarse graining — chunks of matter large enough that they have a reasonably uniform average internal energy — and a “quasi-static” approximation where that average internal energy isn’t changing too fast. This becomes apparent when one actually writes down differential equations derived from first law concepts for dynamical evolution — one perforce has to include things like the heat capacity for the materials/objects (possibly the differential specific heats for extended media) in order to discuss how heat flowing into an otherwise closed system changes its temperature, and even elementary treatments quickly lead one to write down things like the heat equation. Generalizing the reasoning associated with the heat equation to include convection, generalizing it still further to include radiation, generalizing it one last time (in the context of the actual planetary climate) to include latent heat — all of which are highly NON-linear phenomena where the initial discussion of “temperature” as a valid context was highly linearized — one ends up with a really, really hard problem, one where “average temperature” isn’t a terribly useful construct. Compare, for example, 1 kilogram of water at 100C in liquid form to 1 kilogram of water at 100C in vapor form. Yeouch! Not exactly the same amount of internal energy…
This is hardly an irrelevant example in climate science. If Trenberth’s “missing heat” has gone into the ocean, it raises the average temperature of the ocean by an amount so small that it is probably not resolvable with current instrumentation (as I am “skeptical” that we can measure the average temperature of the oceans to millidegree resolution). If that same heat goes into the atmosphere, it raises the temperature enormously — or rather, it doesn’t because the atmosphere cools faster as it warms so temperature increases are self-limited (and predictable only by solving a very difficult nonlinear system). If the missing heat goes into latent heat at the ocean’s surface, it is then mobilized for comparatively rapid transport vertically to heights where, as you note, GHGs actively cool. Predicting the nonlinear dynamics again involves solving complex systems of PDEs in a context where “average temperature” is utterly useless as a metric. It isn’t even clear if “average enthalpy” — the quantity average temperature is supposed in some sense to mirror — is useful.
The problem is that “the Earth” can heat at constant average temperature within our ability to resolve it. It can cool (as in lower its total internal energy) as average temperature rises the ways we currently try to measure it. Our ability to precisely measure energy flow in and out even at the TOA is still highly limited. And everything is nonlinear and complex to the point where — in my opinion — it is still basically incomputable as a meaningful solution to a well-posed problem in physics.
So I agree with you that global average temperature is — something. It is what it is, even though it keeps “changing” as people keep changing the algorithms and data sets used to compute it, especially in the remote past where the errors in measurement and method probably exceed the difference in the current metric and the past estimates. It isn’t irrelevant to discussions of climate, but neither is it the single parameter that it has been turned into supposedly reflecting anthropogenic warming. It is also a quantity that has — in my opinion — countless thumbs on the supposedly objective scales. And then we can discuss the problems with kriging the data, especially kriging with highly sparse lat/long grids mapped into the surface of a sphere with its polar divergence in the spherical-polar Jacobean (one of many reasons I don’t take estimates of temperature in 1890 seriously, even given a very sparse land surface record in parts of the world — the oceans at 70% and whole continents like Antarctica are essentiall unrepresented AT ALL).
Honestly, it is one or the reasons I like RSS and UAH LTT. Very nearly global in extent, reasonably consistent in measurement technology, not horribly sparse, and largely resistant to human confirmation bias and influence, it isn’t “the average temperature” of Earth, but it is what it is, and one can reasonably expect climate changes to be reflected in it over sufficient time. It is also a boundary condition, of sorts, on surface temperature estimates and helps keep them honest when they are far more easily manipulated by data selection and adjustement, sparse, heavily kriged, and STILL undersample vast surface areas of the globe while heavily oversampling others.
rgb
i find fallacy here:
” So, where is the 100x as fast rise in today’s temperature causing this CO2 rise?”
who said you need to boil the beer to release the dissolved co2? have a look at al gore’s famous chart while you’re at it. and 100 times almost nothing is still almost nothing.
and global temperature average? puhleeze. you got one testicle and one ovary? i don’t think there’s any point in this sort of numerology.
@author
Touchy touchy, and cheery picked comment at that
Konrad
Your comment makes me wish that I had a better foundation in physics. Some of your points seem very cogent. Your comments on the assumed black-body character of the earth is a revelation and rings true. It seems that a lot of re-thinking is needed on this business of radiation physics. For example, it has always seemed to me that the so-called “effective radiation level” (ERL) is a contrivance that cannot be supported and is well refuted by other considerations.
Good to have your comments.
Hi Richard S Courtney,
I see the differing approaches as a strength allowing for cross-verification (or not). If everyone was doing exactly the same thing, and making the same errors, how would we know the difference without other methods to check against? The UAH record was improved by having another group (RSS) processing the same data differently.
. “THERE IS NO SUCH THING AS A GLOBAL AVERAGE TEMPERATURE”
It’s an abstraction, like any average. It exists of course, but ultimately in the mind. The real question it seems to me is, is it useful?
I went to the post when it was first referenced and have seen most of Dr. Spencer’s points before that . #7 puzzles me most.
All I can ascertain from #7 (Temperature controls CO2, not the other way) and its explanations is that both are true and neither are true – that neither is the primary controlling factor for the other on this planet and it’s a mistake in approach to think that it’s got to be one thing or the other when it’s very, very likely (99% by my own IPCC-styled deterministic approach) a combination of many, many, many factors known, known to be unknown, and of unknown unknowns.
“Is it CO2 or isn’t it” helps eliminate all other considerations and makes indiscriminant exercise of the precautionary principle in the face of an unproven and totally imagined horrific disaster seem reasonable.
9. THERE IS NO SUCH THING AS A GLOBAL AVERAGE TEMPERATURE Really?! Is there an average temperature of your bathtub full of water?
—–
Yes, but what is it?
Let’s say you fill the bathtub with hot water and measure the temperature of 100 F. An hour later it is 85 F, another hour it has dropped to room temperature of 72F, where it remains.
So what is the average temperature for the water in the tub that day? If you use Min\Max the answer is 86 F. If you measure the temperature every hour the weighted average is 73.71 F.
Let’s say you repeat the experiment the next day, but take the first measurement an hour after the tub has been filled (Time of observation bias). The Min\Max average then becomes 78.5F.
Years later, after installing a new water heater (Urban Heat Island effect) you repeat the experiment and discover the average bathtub water temp has risen.
You expand the experiment to determine the GABT (Global Average Bathtub Temperature), but two thirds of the households (representing the oceans) don’t have tubs, they have showers, so no data from them. And of the remaining third, in many parts of the world they don’t have thermometers (weather stations), so no data from those areas.
Despite these issues, you massage\extrapolate the data and come up with a GABT number and claim it is rising because of some X factor. And the Bathtub Water Science is settled.
PS Where’s my grant money?
I also dispute #9 and find Dr. Spencer’s room analogy sorely lacking. The average temperature of a single room might be useful, but would it be useful to take a temperature of all rooms in a house, from basement to attic, and average them? Not only does each room have a different utility but the statistical properties of each room are very different. For example, rooms directly exposed to the sun will show a much wider temperature change then rooms that are not. Put simply, no one would make a decision about how to control the temperature in all the rooms of a house by considering the average temperature of all rooms in the house. Rather one would consider the temperature range in each room of the house.
Another issue with a global average temperature is it promotes ignorance of the complexity of the global climate. For example, what does it mean when the pattern of changes in the global average temperature differ from the pattern of changes in continent average temperatures. Or what does it mean if the long temperature record in a given city shows little evidence of “global warming” but the global average does?
I suggest if one wants to talk about a “global average” then one be careful about presenting all of the regional measurements that make up the average. This way one can have a much better idea of what temperature measurements are contributing most to changes in the average.
To be fair to those whose feathers have been ruffled, Dr. Spencer replied in the comments section of his blog to many of these concerns. Particularly to some of the more nuanced arguments such as 7. For those who are upset I suggest you head over and actually read the responses. I do agree with what many have said better phrasing could have prevented the untimely deaths of many a straw man.
It’s probably worth tweaking the language to address the fact that the atmospheric greenhouse gas effect is different than greenhouse effect seen in an actual greenhouse.
rgbatduke, probably global mean temperature isn’t the most useful metric (anomalized or absolute) for the physical measurement of the impact of anthropogenic activity on the Earth’s climate system. But it is one of the most economically important metrics, which is why there is so much focus on it: We live near the surface of the Earth, the temperature matters for us, so it is discussed. Whether the deep sea increases by 0.01°C matters less than whether the surface air temperature increases by 1°C.
Ironically, Nick Stokes, hardly a climate sciences skeptic, was one of the people making the absurd argument you couldn’t measure the absolute temperature of the Earth.