Top Ten Skeptical Arguments that Don’t Hold Water

(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.

Advertisements

  Subscribe  
newest oldest most voted
Notify of

Actually, I think it’s a very useful post, and I have no substantial disagreement with any of it.

PaulH

Re. #9, I have no problem with the idea of calculating a global average temperature. My question is, what is the “correct” average (target) temperature, and who decides?

1. THERE IS NO GREENHOUSE EFFECT.
Greenhouses warm by limiting vertical circulation, not by blocking outgoing IR. This can be verified by opening a small window in the roof of a greenhouse, or building a greenhouse out of material transparent to outgoing IR.
Does CO2 warm the planet by limiting vertical circulation? If not, then how can it be a greenhouse effect?

My [Spencer’s] 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!

It’s nice to have achievable goals!
I could quibble with some of the one-liners, but the accompanying text explains the context. Good post, though it does seem to be aimed at people who are certain their thinking is the right thinking. Just like Roy said!

Claude Harvey

Bravo! It’s often embarrassing to see so many skeptics destroy their own credibility by engaging in the poop-slinging contest originated by AGW theory advocates. (“Sling enough on the wall and some of it will stick.”)
“Truth for its own sake” should be the banner under which we march.

James Ard

If we ever get that Skeptic organization going, I nominate Dr. Spencer to be Anthony’s Vice President.

Raymond

I’ll 2nd Paul’s question.

Could Dr Spencer complement this valuable article with its analogue
ie Ten Skeptical Arguments that do hold water?

Liberal Skeptic

Here here. I know you can’t control the comments without getting all draconian but the sort of misinformation debunked above is the worst part of trying to a positive experience out of this website. And what makes it an easy target for alarmists. “Just read the comments, it’s nuts”

There’s a lot of ground to cover here, but the point is taken. You shouldn’t resort to fallacies when fighting fallacies.

Mark Bofill

Excellent post Dr. Spencer. Thank you.

Roy Spencer has done us all a service in his clear and forthright style by clearing away some of the thicket of anti-scientific nonsense that emanates from those who have ceased to be truly skeptical – some of whom may perhaps be paid to come out with rubbish in the hope of discrediting all of us.

Bruce Cobb

This is a pointless exercise, and uses strawman arguments. The quality (or lack thereof) of whatever arguments skeptics make is easily discernible.
The key point is that reality itself is showing that the effect of man’s additional CO2 is minimal. The reason appears to be negative feedbacks. Those pesky clouds have a nasty habit of wrecking climate models.

John West

Bravo!
This was way overdue IMO.
I’d just like to point out that #7 is most likely true pre-anthropogenic influence.

Rich Carman

My response is all positive.

son of mulder

The only bit I disagree with is in No. 9 (but I may have misunderstood your wording).
“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.”
As essentially the only source of heat is the sun and at any temperature, with the system in equilibrium the amount of energy leaving the earth will equal the amount arriving from the sun and since the amount arriving is fixed, so is the amount leaving. If more left for outer space the earth would cool. When less leaves the earth warms.

What effect does adding CO2 to the atmosphere have on water vapor? All things being equal, doesn’t increasing the partial pressure of CO2 by necessity make it harder for water to evaporate, reducing atmospheric moisture and thus reducing the GHG effect of water in the atmosphere?
Isn’t the reduction in atmospheric moisture consistent with long term observations? As CO2 is increasing, isn’t atmospheric H2O is decreasing? Otherwise, wouldn’t atmospheric pressure need to increase as per partial pressure law? Wouldn’t the increase in atmospheric pressure itself lead to warming?

Juergen MIchele

Looking at your point 4. :
CO2 in the upper atmosphere blocks outgoing radiation from the earth surface.
But the incoming radiation from the sun in the relevant frequency range is hundredfold compared to the back radiation from earth.
As a consequence more CO2 cools!

Bob B

Roy, I think your #7 is a strawman argument. I have seen it stated by skeptics that the temperature leads the rise in CO2 in the Vostok ice core records and not the other way around. I believe the data does indeed show that.

Mike M

“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. ”
I take issue with comparing proxy data to direct instrument measurements in general but would also suspect that the farther you go back in time in the ice record – the more molecular migration there will have bled over from one time period to another thus damping the actual rate of change that occurred over any narrow segment of time.
Additionally, stomata count of plant leaf fossils show more or less a slightly but consistently higher level of CO2 than what ice core data suggests. More importantly, stomata count shows a dramatic change in CO2 during the Younger Dryas period as would be expected and is absent/muzzled/diluted in the ice core record. http://geocraft.com/WVFossils/stomata.html
So I don’t agree that #7 belongs on the list.

Tom Stone

Thank you Dr. Spencer. Until today, I was a proponent of fallacy #7. Science is at its best when it challenges itself with observational evidence.

kevin kilty

I expected to see this one on Spencer’s list: CO2 cannot warm the surface from a colder atmosphere because heat does not flow from a colder place to a hotter one.
Spencer’s number nine is a complex one. Certainly one can always measure an average, but in such a complex situation as the one we speak of it is difficult to ensure that two instances of the “average” are truly equivalent–think surfacestations dot org.

jhborn

First, thanks for No. 3. I’d never heard the contention you’re thereby countering, but the discussion if helpful to me.
As to No. 9, though, there are a great many ways in which the global average temperature is misused, so my guess is that many people who make the statement are correct in the context they’re making it in. In other words, we shouldn’t automatically dismiss someone’s criticizing the global-average-temperature concept just because Dr. Spencer says (correctly) that arguments based on its shortcomings are sometimes wrong.

Tom Stone

Some of the more recent posts indicate that I was not so wrong. Even better.

I agree with Bruce Cobb, a pointless exercise. The reality that I see is that warming has stopped. Let the warmists postulate new theories. As a side note: has anyone replicated the numbers from Vostok? Steve Goddard’s exposure of government manipulation of temperature records makes me question any measurement.

Mike M

Bob B says: May 1, 2014 at 6:31 am “Roy, I think your #7 is a strawman argument. I have seen it stated by skeptics that the temperature leads the rise in CO2 in the Vostok ice core records and not the other way around. I believe the data does indeed show that.”
Yes and I use that all the time while emphasizing the alarmist claim that “CO2 took over to push temperature even higher”. So if CO2 pushed it higher then how in the world did it manage to come back while CO2 remained higher? No one seems to give a palpable answer to that question outside of “natural variability”. So then I’ve got them – if “natural variability” was solely responsible for bringing temperature down when CO2 was at or near its highest concentration – WHY should I believe that “natural variability” could not have been solely responsible for the rise of temperature when CO2 was at a lower concentration ?

In science, what happens if you take two different processes and give them the same name? For example, what if you took addition and subtraction and called them both addition. What effect would this have on the mathematics? Wouldn’t this lead to arguments and disagreements over whose answer was correct?
Isn’t this what we see in climate science? Two different physical processes both called “the greenhouse effect”. One involves radiation, the other involves convection. Both using the same name without distinction, yet completely different. Wouldn’t this lead to arguments and disagreements over whose answer was correct?

Len

i third- fourth, whatever the “average” question. with a CO2 caveat.
what IS the “BEST” average temp for humans/the planet?
what is the “Ideal” PPM for CO2 in the atmosphere for Plants.
where -supposedly- did humans Evolve, would not that general climate be “ideal” for us-after all we evolved there…
so that would be -africa-around kenya to be precise according to Berkeley’s evolution website…average temp in kenya is what.. about 23c or so? or about 8c warmer than the earth’s average temp…hmm…..
ideal ppm for plants. well most commercial greenhouses say the plants grow faster and stronger with more co2 in their greenhouses, and they keep it at around 1000ppm of co2 in the greenhouse…so would it be safe to say that doubling or even tripling the amount of co2 in the atmosphere would be better for the plants?
see that is the issue, all the “experts” are saying “CO2 BAD!”…but is it.

dp

I can’t tell you how happy I am that none of the things I’ve ever said are covered in the list.

Peter Miller

I do not have any problem with any of these points
My biggest gripe is some sceptics’ disbelief in AGW – such a belief is total rubbish, what sceptics should be saying is:
1. AGW exists, but its effects are grossly overstated by alarmists, and
2. CAGW is an alarmist myth, without any evidence – especially in the geological record – to support it.

Jaakko Kateenkorva

Let’s see how long it takes for SkS et al to publish a screenshot on their website and construct straw men around them.
For the number 7, It would be interesting to learn more about the mistakes in the charts where the temperature goes up first and then the CO2 follows.

kevin kilty

Oops. My pet peeve is on the list, but I missed it.

David in Cal

Thanks for this, Dr. Spencer.
I have seen it claimed that the climate sensitivity of CO2 (impact of doubling) is something like 1.2 degrees C, in the absence of positive or negative feedback. Three questions:
— Is this correct?
— Does it follow from principles of thermodynamics?
— Has it been experimentally verified?

JimS

Another bad skeptic argument is stating that just one volcanoe eruption can spew out more CO2 than all the CO2 that mankind has ever produced throughout industrial history. This is simply NOT true and I see it being used much too much.

michael hart

Re #9
By a quick-and-dirty SB radiative energy calculation, there are multiple possible combinations (of areas and temperatures) of regions of the Earth which can collectively can posess identical aggregate energy balance. That is, there are multiple possible “average earth-temperature”s for the same energy input-output.
So “What does it mean?”, is certainly a valid question.
Another one is: “What is its use?”

In response to number 4. “CO2 COOLS, NOT WARMS, THE ATMOSPHERE.” I agree with the doctor but if increased CO2 replaces other more effective greenhouse gases such as water vapor or Methane wouldn’t that cause cooling?
If CO2 is going up something else in the atmosphere has to be going down. You can’t have more than a million parts per million. Also you’d think increased CO2 would also cause oxygen to increase due to more plant growth and more photosynthesis. Is there any institution that tracks the makeup of the entire atmosphere?

AlecM

My Dear Roy, you are still so wrong despite my efforts to educate you!
1. Downwelling is a Thermal Radiation Field, the potential energy flux of the Atmosphere to a sink at absolute zero. This is basic Radiative Physics: there is no downwards energy transmission for a normal temperature distribution. The IR thermometer measures temperature because it measures the difference of its Thermal Radiation Field and that of the Atmosphere, and the result is calibrated vs a black body.
2. The imaginary ‘Enhanced GHE’ is a Perpetual Motion Machine of the 2nd Kind; the atmosphere using its own heat to cause itself to expand.
3. Oh Dear! The Tyndall experiment has been badly misinterpreted. There can be no ‘thermalisation’ of the GHG-absorbed energy because that would breach The Law of Equipartition of Energy, as basic a physical principle as quantum theory.
4. CO2 does not warm or cool because it lis the working fluid of the Heat Engine that stabilises surface temperature: more later!
5. See 3 and 4.
6. The Trenberth Energy Budget is juvenile physics. MODTRAN, based on replicating real observations, shows there is ~63 W/m^2 net IR energy flux from the surface to the Atmosphere consistent with 238.5 W/m^2 OLR. The rest of the mean 160 W/m^2 leaves as convection and evapo-transpiration!
7. The dissolution of CO2 in ice has smoothed out the real Vostok data.
8. The IPCC models are deeply flawed in many ways so they cheat to get the political result. Leave it at that for the time being.
9. Ditto……
10. A black body radiating to Space can have an operational emissivity near unity. The Earth has an operational emissivity of about a sixth of a black body. We engineers know this for a fact!
My comments are not negative, simply an attempt to correct the false physics you were taught, originating from Sagan!

Nick Adams

“Re. #9, I have no problem with the idea of calculating a global average temperature. My question is, what is the “correct” average (target) temperature, and who decides?”
Ditto.

Thanks roy.

ThinkingScientist

I think Roy’s argument on No7 is very weak. It is clearly the case that using the Vostok ice core there is a lag of approximately 800 years in the peak cross-correlation between the temperature and CO2 data, with temperature leading CO2. Its a simple point to demonstrate using the downloaded data and a spreadsheet. For that reason, Al Gore’s inclusion of it as irrefutable evidence of globbal warming caused by CO2 is entirely without foundation.
The second point about the rate of increase in CO2 is a non-sequitur. Given the resolution of the Vostok ice core data it is unlikely to “see” rapid changes over short periods.
What we can say about the Vostok ice core data is that there is evidence that there may be a long term, low frequency response where CO2 lags temperature.
Its only by looking at a modern, short term response and corresponding lag that we might identifiy cause and effect between CO2 and temperature on the time scalesof AGW. One hypothesis has been proposed by Murry Salby, as yet interesting but needs developing or refuting.

more soylent green!

5. ADDING CO2 TO THE ATMOSPHERE HAS NO EFFECT BECAUSE THE CO2 ABSORPTION BANDS ARE ALREADY 100% OPAQUE — I have always been curious about this and I appreciate learning why it’s wrong.
9. THERE IS NO SUCH THING AS A GLOBAL AVERAGE TEMPERATURE — You can average anything if you have the data. However, we really don’t know the global average temperature for the simple reason we don’t have the data — we measure too few data points and interpolate too many data points, extrapolate too many data points and too much of the data is junk because of poor station placement. The global average temperature is an estimate.

CaligulaJones

Clear, concise, useful, but perhaps futile: the warmists will demand a list of hundreds of points, until every speck of “gray” becomes black, or white depending on your view.
As mentioned above, #9 is perhaps the most important one, and would be a complete post, or even a complete website, all its own.
I work in health data, and whenever I discuss climate with any of my colleagues, and whenever they point out how clear the warmist argument is, I point out the hours, and hours….and hours of meetings, emails and discussions (often bordering on arguments) about how we measure things. All done by competent, experienced people, and often, totally contradicting each other.

point 7. And we know our consumption of fossil fuels is emitting CO2 200 times as fast!
===============
I don’t understand this sentence. 200 times as fast as what?

Charles Hart

“by Ferd:
1. THERE IS NO GREENHOUSE EFFECT.
Greenhouses warm by limiting vertical circulation, not by blocking outgoing IR. This can be verified by opening a small window in the roof of a greenhouse, or building a greenhouse out of material transparent to outgoing IR.
Does CO2 warm the planet by limiting vertical circulation? If not, then how can it be a greenhouse effect?”
I believe the effect is a a) warmer earth surface or b) a warmer inside greenhouse than would otherwise be the case. The physical mechanism may be different but the effect is the same. Thus it is called a “greenhouse” effect.

steveta_uk

Roy is well short of his 1000 daft responces on his own blog – I assume that the daft responses on WUWT (which oddly haven’t really started yet) can be added to his count.

Jimbo

I don’t actually DISAGREE with any of Spencer’s points. I think it’s important to note that there are varying degrees of sceptics. From Lukewarmers to Dragon Slayers and everything else between.
Look, even if you disagree strongly with Spencer this is no way to fight the battle. They will simply call you the ‘D’ word if you say: “THERE IS NO GREENHOUSE EFFECT”. The debate gets bogged down. Assume the points given above are correct and fight from there and only there.
Vostok ice cores show co2 follows temperature rise but that doesn’t mean it’s the cause of today’s relatively rapid rise of co2. I get it.

Girma

WARMING CAUSES CO2 TO RISE, NOT THE OTHER WAY AROUND

Roy, gere is what the IPCC says, not skeptics:
CO2 is more soluble in colder than in warmer waters; therefore, changes in surface and deep ocean temperature have the potential to alter atmospheric CO2.
https://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-4.html

Jimbo

Spencer needs to follow his post with
Top Ten Warmist Arguments that Don’t Hold Water
EG
Co2 is the most important greenhouse gas.

IPCC – Climate Change 2007: Working Group I
Water vapour is the most important greenhouse gas, and carbon dioxide (CO2) is the second-most important one. ”

Girma

WARMING CAUSES CO2 TO RISE, NOT THE OTHER WAY AROUND

Roy, here is what the IPCC says, not skeptics:
CO2 is more soluble in colder than in warmer waters; therefore, changes in surface and deep ocean temperature have the potential to alter atmospheric CO2.
https://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch6s6-4.html

Marc77

The only problem that I have is the certainty that the greenhouse effect warms the nights more than the days. A lot of people feel it it is clear, but no one makes a good proof.