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Preventing Misinformation

Posted on 22 March 2011 by dana1981

A few individuals and groups have queried Skeptical Science about a misleading and myth-filled climate page from  The page is actually a re-post of a document put together by amateur astronomer Gregg D. Thompson.  We at Skeptical Science aim to please, so here we will examine the claims made in this document.  Since it consists almost entirely of long-debunked myths, most of our response will consist of linking to existing rebuttals in the Skeptical Science database.  Unfortunately, but unsurprisingly, the document contains no supporting evidence or references, so we will evaluate its arguments on their own merit (and lack thereof).

Human Emissions are Small

The document begins by making a number of irrelevant and misleading statements about human carbon dioxide (CO2) emissions.  The three principle misleading statements and errors are:

"CO2 is less than a mere four 100ths of 1% [of the atmosphere]"

"Humans produce only 3% [of global CO2 emissions]"

"If the public were aware that man-made CO2 is so incredibly small there would be very little belief in a climate disaster"

These statements presume that anything that is present as a small proportion can have no effect, which is clearly nonsense.  In reality, the percentages of CO2 in the atmosphere and of human CO2 emissions are irrelevant to the risk that those emissons pose. A very small proportion of arsenic in drinking water can be very dangerous, for example. 99% of the atmosphere is composed of non-greenhouse gases, so the entire greenhouse effect is caused by the remaining 1%

The second statement ignores the fact that although natural emissions are much larger than human emissions, the natural carbon cycle is in balance.  Natural carbon sinks absorb more than natural carbon sources emit, and human emissions upset that balance.  That's why humans are responsible for the 40% increase in atmospheric CO2 over the past 150 years.

CO2 as a Pollutant

"CO2 is a harmless, trace gas. It is as necessary for life - just as oxygen and nitrogen are. It is a natural gas that is clear, tasteless and odourless. It is in no way a pollutant."

They key to qualifying as a "pollutant" is whether it poses a threat to public health and welfare.  CO2 clearly creates this threat through climate change, and thus qualifies as a pollutant.  The fact that CO2 is colorless, tasteless, and odorless is completely irrelevant.  The argument that CO2 is necessary for life, implying that it therefore can never cause harm, is nonsense.  Water is equally necessary for life, but too much of it can be fatal.

The Greenhouse Effect

"There is no proof at all [that CO2 causes a greenhouse effect]. The Intergovernmental Panel for Climate Change (the IPCC) has never produced any proof. There are, however the following proofs that it can’t cause a greenhouse effect."

The fact that CO2 is a greenhouse gas has been known for over a century.  John Tyndall measured the CO2 greenhouse effect in laboratory experiments in 1859.  To claim that there is no proof that CO2 causes a greenhouse effect is, to be blunt, a sign of extreme ignorance regarding basic climate science, and a red flag that Thompson and have not done their homework.

"It is true that CO2 can absorb heat a little faster than nitrogen and oxygen but it becomes no hotter because it cannot absorb anymore heat than there is available to the other gases. This is against the laws of thermodynamics."

If this argument were true, the greenhouse effect would not exist, which is obviously not the case.  It has been debunked in The Greenhouse Effect and the 2nd Law of Thermodynamics.

"Even if CO2 levels were many times higher, radiative heating physics shows that it would make virtually no difference to temperature because it has a very limited heating ability. With CO2, the more there is, the less it heats because it quickly becomes saturated."

The document goes from arguing that CO2 is not a greenhouse gas, to arguing that the greenhouse effect does not exist, to arguing that the greenhouse effect exists, but atmospheric CO2 is saturated.  The number of self-contradictions is rather appalling.  Regardless, the atmospheric CO2 greenhouse effect is not saturated.  Adding more CO2 to the atmosphere effectively adds more layers to absorb outgoing infrared radiation and re-emit some of it back towards the surface, increasing global warming.

More Greenhouse Misunderstandings

"The planets Venus and Mars have atmospheres that are almost entirely CO2 (97%) yet they have no ‘runaway’ greenhouse heating effect. Their temperatures are stable."

The temperatures of Venus and Mars are stable because the amount of CO2 in their atmospheres is stable.  A "runaway greenhouse effect" occurs when something warms the planet, triggering positive feedbacks which warm it further; however, even this  does not mean the planet continues warming infinitely, forever.  In fact, positive feedbacks do not necessarily lead to 'runaway warming'

Venus appears to have undergone a runaway greenhouse effect long ago in its history, but has now stabilised.  Venus is twice as hot as Mercury, despite being twice as far from the Sun, in large part because of the greenhouse gases in its atmosphere.  And Mars isn't particularly hot because its atmosphere is thin and has little water vapor - another greenhouse gas.

"The geological record over hundreds of millions of years has shown that CO2 has had no affect whatsoever on climate. At times, CO2 was hundreds of times higher, yet there were ice ages."

CO2 is not the only factor which impacts global temperatures, but to infer that it therefore cannot have any effect is nonsense, akin to saying that not all deaths are due to cancer, therefore no deaths are due to cancer. 

Over billions of years, the Sun has become gradually brighter.  Over millions of years, movements of continents and the rise and fall of mountain ranges has had great effects on our climate.  Over tens of thousands of years, Milankovich cycles have increased and decreased seasonality, leading to periods of greater ice cover which in turn reflect away sunlight, cooling the planet.  However, through it all the geologic record tells us that the climate is quite sensitive to CO2, and that CO2 is the principle control knob for the Earth's temperature.

Medieval Misinformation

"Earth was considerably warmer during the Roman Warming and the Medieval Warming"

This is simply false.  Every peer-reviewed millenial temperature reconstruction shows current temperatures hotter than during the Roman and Medieval periods.

Water Vapor

"Water vapour is 4% of the air and that‘s 100 times as much as CO2. Water vapour absorbs 33 times as much heat as CO2 making CO2’s contribution insignificant."

Water vapor is a feedback, not a forcing.  Furthermore, as Lacis et al. (2010) found:

"Because carbon dioxide accounts for 80% of the non-condensing GHG forcing in the current climate atmosphere, atmospheric carbon dioxide therefore qualifies as the principal control knob that governs the temperature of Earth."

Winter Temperatures

"Over the last few years Earth has had much colder winters"

This is another blatantly false statement.  The average global surface temperature continues to rise during every season.  In fact, winters are warming faster than summers!


Arctic Ice and Glaciers

"the Arctic has re-frozen and glaciers that were receding are now surging due to the heavy snow falls."

Once again, the document makes completely false assertions.  Arctic sea ice continues to decline rapidly, as does global glacier mass.

Blaming the Sun

"as the Sun is now entering probably 2-4 decades of low solar activity, this is expected to cause global cooling."

Solar activity has been flat over the past half century, during which time global surface temperatures increased over a half degreee Celsius.  The Sun is not driving global temperatures.

The 1934 Myth

"The hottest records in the USA and Greenland were in the 1930s due to a strong solar cycle."

First of all, the USA and Greenland are not the world.  The global surface air temperature is currently approximatley 0.6°C hotter than it was during the 1930s.  Secondly, today's temperatures are hotter than the 1930s even in the USA and Greenland.

Mid-Century Cooling

"It became cooler from 1940 to 1970. This was due to a weak solar cycle."

The mid-century cooling was not caused by the Sun.  In fact, solar activity increased slightly between 1940 and 1970.

Recent Temperatures

"It has again become increasingly colder since 2006 due to another weak solar cycle."

Although five years is far too short of a timespan to determine a significant trend, the trend since 2006 is positive (warming).  2009 and 2010 were two of the hottest years on record, despite the weak solar cycle.


"We were told CFCs caused the Ozone ‘hole’ yet after billions of dollars were spent removing CFCs over 30 years, the slight depletion of Ozone at the South Pole has not changed. Scientists now think it is natural."

The ozone layer is recovering, and scientists still think its depletion was caused by human chlorofluorocarbon (CFC) emissions, because that's what the scientific evidence indicates.   However, we only started seriously reducing CFC emissions 20 years ago (with the Montreal Protocol - the ozone version of the Kyoto Protocol), and CFCs have a long atmospheric lifetime, so the recovery will take time.  There are of course ozone "skeptic" scientists just like there are global warming "skeptic" scientists, but the consensus and evidence are not in their favor.

Carbon Pricing

"A carbon tax will have a disastrous impact on lower and middle income earners."

Fear of a carbon tax may be the underlying motivation behind this ill-conceived document.  However, the benefits of carbon pricing outweigh its costs, and results in smaller economic impacts on lower and middle income households.

Gish Gallop City!

As you can see, this document is little more than a Gish Gallop of Moncktonian proportions.  It's merely a result of Thompson not taking the time to learn some basic climate science, putting together a document full of misleading misunderstandings and misinformation, and propagating that misinformation.

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Comments 51 to 72 out of 72:

  1. Okay through my digging I found some equally stupid. It turns out that you can use climate models as an “instant replay” to recreate a specific weather event. Think of it like doing an autopsy, except it’s being performed on a specific extreme weather event. The European heat wave of 2003, an extreme weather event that killed over 35,000 people, offers the best example of how climate models can help us see the global warming embedded within our weather.
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    Moderator Response: [muoncounter] See the thread on extreme weather; nothing 'stupid' about it. At least make an attempt to find out how things work here.

    [not muoncounter] ...and comment further on that thread, not this one.
  2. "...carbon dioxide therefore qualifies as the principal control knob that governs the temperature of Earth." This would mean that the effect of white cloud tops reflecting sunlight has less effect on temperature than CO2, but of course this is not true, just as the nonsense herein quoted.
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  3. Dana I'm sorry but that's really just an embarassing, false claim. Yeah, here's my evidence that it's wrong. There are floods every year.
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    Moderator Response: [muoncounter] Apparently you are unaware that the term '100 year flood' has specific meaning; it does not occur every year (it would then be called the 'annual flood'). [Dikran Marsupial] Not all floods are of equal severity, the claim was that you should expect to see a flood of that severity or greater once in a thousand years. It doesn't mean that there will be a flood once in a thousand years. It is generally consideredna good idea to make sure you properly understand a claim before trying to refute it.
  4. Well if you want to say that Tennesse had not had a flood that bad in 1000 years, that is different. However, we also know that there have been far, far more powerful storms in the past. In fact, I would say if you start at 1970, I could offer a counter example to any weather event that was stronger in the past.
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    Moderator Response: [Dikran Marsupial] (correction) That isn't the claim either. The claim is not that a flood that bad had not occurred in the last 1000 years, but that a flood that bad is expected on average every 1000 years. There is nothing to prevent two "one in a thousand" floods happening in consecutive years, it is just very unlikely (one in a million assuming independence). Thus your challenge is also misguided as it misrepresents the statistical nature of a statistical statement.
  5. Dr. Cadbury >There are floods every year. I think it is fairly self-evident that when someone refers to a 1 in a 1000 year flood event, they are talking about a flood in a specific location with a specific severity, not the idea of flooding in general. I find it fairly disingenuous that you are attempting to spin this rather straightforward concept into a point of contention.
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  6. Jay, are there floods of that magnitude in that location every year? I hope you'll agree the answer must be no. At which point we might ask, 'well how often on average does a flood of that magnitude happen in that location'... and apparently the answer to that based on available data is about every thousand years.
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  7. Jay, I think you might benefit by slowing down and reading through some of the 'Most Used Skeptic Arguments'. As it is you seem to be flitting from one wild accusation to the next without stopping to breath. There is a ridiculous amount of information on the site and alot of these issues have been addressed previously. Why not read up and then find the proper threads to lay out in detail the strongest objections you can think of? Rather than some random person at a single hearing said something about a 'thousand year flood'... which obviously has about zero bearing on the overall question of whether AGW is a significant issue or not.
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  8. RSVP #52 -
    "This would mean that the effect of white cloud tops reflecting sunlight has less effect on temperature than CO2, but of course this is not true"
    Would you care to provide some evidence to support your claim besides "of course"? I've found that when somebody prefaces a statement by saying something like "obviously" or "of course", the statement which follows is based on little more than their "common sense", and is thus usually wrong. These terms are also used to dissuade people from questioning their factually incorrect assertion. "I don't have to prove it, because it's obvious!". Cadbury #53 - in the future, please take the time to understand what a person is saying before describing them as "preposterous" or "embarassing" [sic]. First off, floods do not happen in every geographic location every year. Secondly, floods have different magnitudes. Maybe that particular area of Tennessee floods once every 10 years, but the flood might only be as large as the 2010 flood once every 1,000 years. In which case it is a 1 in 1,000 year event. This is a really basic concept. It's not Dr. Cullen who should be embarrassed right now.
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  9. dana1981 at 06:54 AM, the RSVP statement is possibly based on daily observations where apart from the day night cycle, clouds are the next biggest factor in controlling the amount of solar radiation reaching the ground. Also perhaps as far as the energy budget goes, 23% of the average 340 watts per square metre total incoming solar radiation being reflected or absorbed by clouds.
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  10. johnd - that still doesn't support RSVP's statements. For example, if the amount of cloudcover never changed, it would cause zero change in global temperatures, even though it plays a large role in the Earth's albedo.
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  11. dana1981 #60 Should cloud coverage go up or down with global warming? If sea temperature overall increases, that would imply more water vapor, I assume, and I also assume more water vapor means more clouds. And more clouds means albedo goes up. Or are you going to say it is the other way around?
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  12. RSVP, it is much more complicated than that. Cloud formation requires alot more than just water vapor in the air. Temperature, pressure, and particulates for the water vapor to condense around all play a major part. Further, clouds are extremely effective at retaining heat in the same fashion that greenhouse gases do (which is why cloudy nights are warmer than clear nights)... and the albedo vs greenhouse warming balance of clouds varies with their altitude. Studies of all these phenomena are ongoing and still have conflicting/disputed results. There seems to be a slight preponderance of evidence that clouds are having/will continue to have a small net warming effect, but that is by no means conclusive. What can be said fairly clearly is that there is absolutely no evidence that the impact of clouds will be significant enough to offset any of the major warming forcings and feedbacks... even if we assume the best case possible cooling impact from the range of uncertainty of the data their net impact is tiny in comparison to warming effects. Lindzen, Spencer, and others have suggested fanciful ways in which clouds could have massive hitherto unknown cooling effects (e.g. the 'cloud iris' hypothesis), but as each of these has been examined the data has shown otherwise.
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  13. RSVP #61 -
    "Should cloud coverage go up or down with global warming?"
    See "What is the Net Feedback from Clouds?".
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  14. dana1981 at 06:27 AM, can you clarify how you think we should view the labeling of these extreme events. You have it correct in recognising them as weather events, and thus right in attaching them to a particular location. However when talking in terms of climate, particularly global climate, can you show that whilst the 2010 Tennessee floods may be able to be deemed as a 1 in 1000 year event for that particular location in that particular state, did it alter the total number of those deemed 1 in 1000 year events that occur periodically world wide? We expect weather patterns to constantly shift, so we need to be certain that we aren't being held hostage to merely shifting weather patterns.
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  15. johnd - it's well established that climate change "loads the dice" and makes floods and a number of other extreme weather events more likely to happen. What used to be a 1 in 100 event may become 1 per decade, for example.
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  16. CBDunkerson at 21:39 PM, I believe it is even much more complicated than what you indicated. Whilst changes to the total amount of cloud coverage is yet to be adequately quantified, and historically probably impossible to determine, there is also the matter of geographic distribution. If the distribution changes over a varying surface then the solar radiation either being absorbed or reflected by the soil or water will also change. Human influence on the landscape causing deforestation, particularly through the era of wooden boat building obviously changed the landscape generally in coastal regions which in turn changed the cloud coverage pattern as reflected in the known changes in precipitation patterns.
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  17. dana1981 at 07:25 AM, can you provide some references that quantify the change in such events globally.
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  18. johd #67 - not off the top of my head, no. You could find them as easily as I could. Google Scholar is your friend.
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  19. dana1981 at 02:19 AM, I am disappointed that you are unable to readily provide such references. That is not upholding the general spirit of SkS in that it is expected anyone making assertions,or even expressing opinions, should at least provide links to support their claims. Whilst the matter of extreme events has been raised in a number of threads, generally relating to specific weather events such as the recent floods in Australia for example, or as you mentioned, the Tennessee floods, there has been no thread that I know of that has addressed it statistically rather than emotionally. One of the points that needs to be resolved is the apparent conflict in some peoples minds of, one hand, attributing some such extreme events to conditions such as the current La-Nina for example, yet on the other hand, maintaining a general assertion that such systems are oscillations that are not indications of any trends. An event such as the Brisbane floods is a weather event, not a climate event. From an Australian climate perspective the actual event is this current La-Nina coinciding with a -ve IOD. Perhaps you would like to present such a review on extreme climate events on a new thread?
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    Moderator Response: [muoncounter] See the thread on Extreme weather. The key take-away is, as dana pointed out, simply one of increasing probabilities of extreme events due to warming.
  20. re "Moderator Response: [muoncounter] See the thread on Extreme weather." There seems to be a lack of links to studies there also, something pointed out, but remains unaddressed.
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  21. We've been meaning to do the extreme weather rebuttal, but there are only so many hours in the day. We're only human. The research is out there though, I've previously read a number of studies on the subject. I just can't produce them without re-doing a Google Scholar search, which you could do just as easily as I could. One quick example I can provide is Peduzzi 2004.
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  22. dana1981 at 05:00 AM, thanks for the link, but. Peduzzi 2004 as an example, after taking away references to earthquakes and the media, all that is left is questions not answers. Hardly something to support any opinions. The research may well be out there, but it appears not something readily produced to support opinions as I referenced regarding the "Extreme Weather" thread.
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