Renowden has no evidence for CAGW

Jo Nova's take on the lack of evidence for AGW

This is in response (slightly delayed by an Easter break) to the list of “proofs” produced by Gareth Renowden, at Hot Topic, in answer to my request of Sir Peter Gluckman, the PM’s scientific advisor, for evidence of a human cause for anticipated dangerous climate change, more properly referred to as the catastrophic anthropogenic global warming (CAGW) theory.

On 17th April, I wrote:

I would remind Sir Peter that evidence is required to establish the following key factors in the global warming debate — evidence that has not surfaced so far. We have been looking for evidence to show:

1. The existence of a current unprecedented global warming trend.
2. That the greenhouse effect is powerful enough to endanger the environment.
3. A causal link between human activities and dangerously high global temperatures.
4. That climate models have a high level of skill in predicting the climate.
5. A causal link between atmospheric levels of carbon dioxide and global temperatures.
6. A causal link between global warming and the gentle rise in sea level.

In response to this, Gareth claims “there is plenty of evidence to address every one of his points” and presents some attractive and interesting graphics in support. I’ll comment on what he says to each point.

1. The existence of a current unprecedented global warming trend.

GR: “…is [the current warming] unprecedented…? Well, no.”

This is most unexpected from the foremost warmist blogger in the country. No comment by me could improve his answer, because he agrees with me unequivocally. I will simply point out that his dark reference to past “major extinction events” is mere arm-waving. The lack of evidence for any current abnormal warming is, by itself, fatal to the whole CAGW theory, because it means that all the CO2 which humanity has “spewed” into the atmosphere over the last 70 years or so has had no undue effect on the temperature. Why then should we believe the forecasts of doom?

Note that Renowden mentions “pedants”, claiming that only they would consider it important whether the warming was “unprecedented.” But, of course, any reasonable person would want to know whether the recent warming was unusual.

2. That the greenhouse effect is powerful enough to endanger the environment.

GR: “The greenhouse effect is powerful enough to deliver the environment we live in, by retaining enough heat to lift surface temperature by about 33ºK.”

I must agree with that summary, as it seems to be widely agreed, although it is certainly disputed, and not settled science. But it includes all of the so-called greenhouse gases, not just CO2. Carbon dioxide contributes a paltry 4% or so of the total natural greenhouse effect, with the man-made portion coming to about 0.1%. Although the exact amount is controversial, it is undisputed that water vapour induces a hugely greater warming than CO2 does. So the “greenhouse effect” raises the temperature, but Renowden gives no evidence for a dangerous temperature rise from our CO2 emissions — and considering the logarithmically declining response of temperature to increasing CO2, it’s impossible. He agrees with the usefulness of CO2 in producing our current environment, which I strongly endorse, but he gives no evidence for dangerous warming.

That’s two down, only four to go. Score: CCG – 2, GR – 0.

3. A causal link between human activities and dangerously high global temperatures.

GR provides this graphic from Sceptical Science:

human fingerprints on global warming

This is highly diverting but of little relevance. “Less heat escaping to space” and “More heat returning to Earth” are directly relevant to the greenhouse effect, but not to a human influence, however, both points have been disproved by Spencer and Lindzen.

The remaining points prove nothing of a human influence. Some are evidence of warming, but not of its cause. The whole thing looks like a simplistic rehash of Trenberth’s attempt at an energy balance. Where are nights warming faster than days? (Not that it shows a human influence anyway.) What is the evidence for a lower level of atmospheric oxygen and how does it show a human influence?

Score: CCG – 3, GR – 0.

4. That climate models have a high level of skill in predicting the climate.

GR claims the models do “pretty well” but then asks: “do you really want to risk waiting a decade or two to see how current models perform? Doesn’t strike me as wise, given 1. and 2. above…”

“Pretty well?” Would you engage a brain surgeon who had done “pretty well” in his final exams? Would you commit the nation to spending billions of dollars based on forecasts that are “pretty well” accurate? Would you require only “pretty good” engineering assessments before commissioning foreshore protection works? This is a nonsense, and Gareth knows it. We don’t need absolute certainty, but we sure as hell demand better standards for our public policy than “does pretty well”!

Climate models actually don’t do very well without a blizzard of fudge factors to account for such things as aerosols during the 1950s and 1960s, when temperatures were dropping, the effects of clouds and even the greenhouse effect itself. In other words, they don’t do everything from first principles, not by a long shot. The models failed to predict the recent fall in ocean heat content, they cannot predict the great ENSO ocean fluctuations that strongly influence global temperatures, they are programmed to believe that low-level clouds cause warming, while real-world observations show they cause cooling, and they predicted that global temperatures for the last 15 years would rise, when in fact they have been in stasis or mild decline.

I guess you could say that, apart from that, they do work “pretty well.”

Since Gareth failed to score on points 1 and 2 above, his argument that it “doesn’t strike me as wise, given 1 and 2 above…” fails, too, as it relies on them. If models performed skilfully in hind-casting global temperatures, we wouldn’t have to wait to verify them, but they fail. One of the reasons for their failure is our low level of scientific understanding of the climate, which is acknowledged by the IPCC, though not widely publicised. The models aren’t magic, they echo scientific understanding at every point and where that is deficient the models are crippled and lose touch with reality.

All the climate models consistently predict a “hot-spot” in the upper troposphere which is just as consistently missing in real-world observations. This shows the lack of skill of the models and allows us to dismiss them as reliable indicators of future climate.

To illustrate this, here’s a graphic which David Evans kindly offered, taken from data in the IPCC AR4, 2007. The original is available at Jo Nova’s web site.

missing tropospheric hotspot

Score: CCG – 4, GR – 0.

5. A causal link between atmospheric levels of carbon dioxide and global temperatures.

GR: “Treadgold’s blockhead moment.”

Actually, I agree to the extent that my point was loosely phrased, and Gareth took full advantage. I was looking for evidence of a correlation between atmospheric levels of carbon dioxide and global temperatures. Gareth simply referred to the (disputed) greenhouse theory but cannot be faulted for omitting to quantify it, because I didn’t ask him to.

But he is wrong to state: “More CO2 means more heat retained in the system, or the greenhouse effect he seems to admit exists wouldn’t. That’s about as clear a link as you can get.”

That’s an incorrect characterisation of the process, as little further significant heat can be caused by further increases in atmospheric carbon dioxide, because the temperature response to CO2 is logarithmic. Gareth should know this. For each new portion of CO2 added to the atmosphere, less and less is added to the temperature. This doesn’t invalidate the greenhouse effect itself, even though Gareth says it does. It is a link, but it cannot lead to dangerous temperatures from mankind’s emissions.

But, because I mis-stated the question, I’ll have to give him the point. Score: CCG – 4, GR – 1.

6. A causal link between global warming and the gentle rise in sea level.

GR: “More basic physics that seems to have eluded Treadgold. If you warm up water, like most things it expands. Thermal expansion has been (until recently) the single biggest contributor to sea level rise and will continue to play a big part until the oceans reach thermal equilibrium — and that will take hundreds of years, even if we do manage to end our binge on fossil carbon.”

Thanks for the explanation, Gareth.

My question was faulty; by “global warming” I meant “anthropogenic global warming.” I want evidence that that part of global warming caused by mankind (if such a part exists) has caused any part of the gentle rise in sea levels observed for several hundred years.

There is no such evidence, because there is no evidence of a human contribution to global warming, and no warming at all since around the turn of this century.

The March, 2011, Washington Post story he references concerns a paper reporting up to another six inches (150 mm) of sea level rise by 2100 to be caused by the “vast ice sheets of Greenland and Antarctica.”

Six inches does not concern people of ordinary nervous systems. But they claim the ice sheets “are melting faster than previously estimated and that melting is accelerating.”

The paper does not measure the outflow of melted ice (an impossible task), so we don’t even know that ice actually melted. It becomes vital to know why the ice sheets are diminishing. It does not have to be rising atmospheric temperatures — it is highly likely to be diminished snowfall.

Diminishing glaciers are not necessarily evidence of increasing temperature. As this story is not evidence of global warming, it cannot be testament to a link between that and sea level rise.

Score: CCG – 5, GR – 1.

Bad luck, Gareth, you lose.

Whatever Mr Renowden might say about my personal motivations and expertise, he must at some point address what I say about the lack of evidence, which is far more significant — especially points 1–4: there is no unprecedented warming trend, no potentially dangerous greenhouse effect, no proof we’re causing dangerously high temperatures, and no evidence of climate model skill.

Perhaps Gareth’s friends in NIWA might give him a hand with this? He claims there’s evidence but has not disclosed any. I still don’t believe it exists.

Views: 97

32 Thoughts on “Renowden has no evidence for CAGW

  1. Huub Bakker on 30/04/2011 at 8:29 am said:

    On question 2:

    Actually Richard, as I understand it, this is a popular piece of misinformation. The greenhouse effect has nothing to do with the “33K” increase in temperature. It relies upon the idea that the Earth would be 33C cooler if the atmosphere were not there. However, it is the compressive effect of the gases in the atmosphere that produce this increase. It is responsible for the ‘adiabatic lapse rate’ that shows temperatures declining as you go upwards to lower and lower pressures. This is why Venus is so much hotter than the Earth (apart from being closer to the sun); it has 40 times the atmospheric pressure at the surface. If it was a greenhouse gas effect then Venus would be much hotter still because of its high concentration of carbon dioxide and water vapour. So too would Mars, which is 90-something percent carbon dioxide.

    The case can be argued the other way too. According to the same argument (that there is a 33C increase in temperature due to the greenhouse effect) the Moon can be shown to have a greenhouse effect because its day and nighttime temperatures are not as hot or cold (respectively) as they should be. In this case it is the thermal heat capacity of the surface layers, which trap heat during the day and release it at night, that are the cause.

    • Yes, I agree. I just thought I’d take advantage of his statement in other ways and avoid an essentially distracting argument.

      Thanks for the description of the “compressive effect.” First time I’ve heard it.

    • Huub Bakker on 30/04/2011 at 3:38 pm said:

      Actually, the lapse rate (decrease in temperature with height) is caused by the ‘well-known’ thermodynamic principle that gases heat up when compressed and cool down when they expand. This is what happens as gases circulate vertically due to being heated by the ground etc; as they ascend and expand, they cool down. Having given up their heat high in the atmosphere they descend and are heated. This means that circulation will maintain a temperature profile, the lapse rate, solely because of the difference in pressure.

      Therefore, saying that the difference in temperature between an Earth without an atmosphere and one with an atmosphere is solely due to greenhouse gases, and that this is 33C, is nonsense.

  2. Anthropogenic Global Cooling on 30/04/2011 at 10:29 am said:

    When faced with the irrefutable truth over how faulty the AGW hypothesis has proven to be, and how little evidence there is for it, the anthropogenic global warmer will look to find some way of undermining you on personal level. Failing that they will put their head in the sand and outright lie. Ken Perrot was the best one for this, ignore all the glaringly obvious evidence disputing AGW and making a personal attack, all the while failing to address ANY of the fatal flaws in AGW

    Warming is not a sign of anthropogenic induced warming, and what little effect CO2 does have is so minimal as to be largely irrelevant. Without the assumed feedbacks that have failed to eventuate, AGW theory is baseless. Some people just can’t admit they’re wrong, I only wish they’d do it with their own wallet instead of mine.

  3. Richard C (NZ) on 30/04/2011 at 12:54 pm said:

    GR’s “clear” link is:-

    “More CO2 means more heat retained in the system”

    An explanation by Gareth of the thermodynamic mechanism of the “clear” “link” at a molecular level would be helpful (shouldn’t be difficult because it’s “clear”).

    Having done that, he could give his clause considerable credibility by informing the world where exactly “more” heat is being “retained in the system” (i.e. the empirical proof). The location would be very helpful to Kevin Trenberth given his difficulty in tracking it down (inadequate observing systems apparently).

    Puckerclust at least had a go at the “Physics Facts” but all he got for his efforts was an inevitable slapping – your turn now Gareth. To help you avoid Puckerclust’s pitfalls, here’s the chronicle of his demise:-

    PHYSICS FACT #1: The atmospheric carbon dioxide concentration has increased rapidly since the beginning of the industrial revolution, after being nearly constant for thousands of years.

    FACT: If the “beginning of the industrial revolution” is defined as mid-18th century, this is NOT true. There are published measurements of aerial concentration of CO2 above 400 ppmv in the 1800s. A further illustration of the variability of atmospheric carbon dioxide can be learnt from Ernst-Georg Beck’s accurate chemical analysis covering 180 years.

    Carbon dioxide cycles with temperature spikes as evidenced by the graph below. A temperature spike is followed by a CO2 increase as ocean temperatures rise and the solubility of CO2 decreases.

    chart 1

    Raw Antarctic ice core measurements from Siple show 328 ppmv for 1897 – the value reached in Mauna Loa measurements of “rapid increase” only in 1970. See: Climate Change: Incorrect information on pre-industrial CO2; March 19, 2004; Statement of Prof. Zbigniew Jaworowski, Chairman, Scientific Council of Central Laboratory for Radiological Protection, Warsaw, Poland.

    PHYSICS FACT #2: The surplus carbon dioxide has an isotope composition that can only come from fossil fuels. The increase in concentration is not natural; it comes from human activities.

    Now suddenly the reported increase is a “surplus”?

    FACT: The whole idea of a definitive human isotope signal is based on one paper only, the Prentice Study, which was entirely an inside UN IPCC job, not peer-reviewed and containing a fatal error: Prentice wrongly assumed that human emissions of CO2 from burning hydrocarbon fuels are responsible for the claimed isotope depletion. In fact, all plant carbon is similarly isotope depleted through natural decay, thus adding greatly to the total. As such the purported “human signature” is based upon a false premise and Prentice vastly exaggerated the contribution from humans. As an aside, all C3-type plant carbon is equally C13-depleted as carbon from fossil fuels and C3-type plants make for 95% of all existing green plants; CO2 from plant decay is a magnitude greater than all human emissions. The “signature” of human emissions is completely lost in the noise of natural CO2 emissions. For further details see Carbon cycle modelling by Tom Segalstad.

    As a corollary to the isotope change, the relatively low amount of C13-depleted carbon in the air points to a rather fast natural turnover rate, a residence time in the neighborhood of only 5 years, not the hundreds of years that is commonly supposed. This low-ball estimate of an anthropogenic impact is roughly consistent with IPCC/DOE figures which show a yearly human CO2 contribution of only about 3%, with Nature providing the other 97%. Combustion alone cannot explain the (reported) 105 ppm increase of CO2 since 1850. The isotope record says different.

    Further information available upon request.

    PHYSICS FACT #3: The radiative properties of carbon dioxide have been measured by physicists in the laboratory: It absorbs thermal infrared (heat) radiation.

    FACT: Carbon dioxide absorbs and immediately emits radiant energy, in fact emits this energy at a longer wavelength than it is able to respond to again. A physicist who claims to understand the earth’s main climate parameters should understand this.

    Besides which, CO2 only absorbs-emits a very small fraction of the IR spectrum, and therefore can never warm up to the same temperature as the radiation source. In other words, if warmed by radiation alone, CO2 will ALWAYS be far cooler than a heat source that’s radiating a continuous spectrum. In Earth’s atmosphere, CO2 warms just like every other gas does – by contact with the ground and by colliding with other air molecules. The scattering of IR by CO2 cannot increase the temperature beyond this.

    PHYSICS FACT #4: Because carbon dioxide has this heat-absorbing physical property, the increase in its concentration has increased the infrared opacity of the Earth’s atmosphere and blocks the outward radiation of heat.

    FACT: Heat absorption does not imply heat blocking. Indeed, if you’re overly hot you’ll naturally seek out a heat-absorber to cool you – for instance, an ice cube. By direct contrast, a heat blocker would obviously impede your ability to cool off. If one imagines that heat absorption does mean heat blocking, however, this will probably lead one to believe that so-called greenhouse gases must create an insulative hot spot, as the IPCC predicted there had to be. But these two charts show the difference between prediction and reality.

    ch2Intergovernmental Panel on Climate Change (IPCC), 2007, p. 675, based on Santer et al, 2003. See also IPCC, 2007, Appendix 9C) and David Evans, “Carbon Emissions Don’t Cause Global Warming”, November 28, 2007

    Rather than a menacing hot spot hovering over the equator, there’s a pleasant cool spot instead.

    To repeat, absorption doesn’t mean blocking. Despite questionable alarmist reports like #5 below, in fact, the earth has long been observed to emit the SAME magnitude of energy as it gets from the sun.

    There is no evidence of blocking.

    PHYSICS FACT #5: More net energy is now coming into the Earth’s atmosphere from sunlight than is going back out to space as heat radiation.

    First of all, formulating an energy budget involves approximately 342 watts per square meter to start with and encompasses at least a year of observations that include variables like solar output, cloud cover, albedo changes, convective currents, and the like. No instrument or method is perfect and a disparity of a few watts per square meter is to be expected.

    Secondly, outgoing (IR) longwave radiation (OLR) is a rather undulatory phenomenon…


    …so it’s always hard to assess whether an actual trend is occurring.

    Third, this recent NASA report (September 2010) seems to indicate that nothing outside the norm is noteworthy anyway.

    Source: Comparisons of Top-of-atmosphere Radiation Budget from Multiple Data SetsSource: Comparisons of Top-of-atmosphere Radiation Budget from Multiple Data Sets

    If Mr Puckerclust has proof to back up his claim, then, we’d like to see it.

    PHYSICS FACT #6: Conservation of energy is a fundamental law of physics. When more energy comes in than goes out of a system, it warms up.

    Translation: If outward energy (loss) doesn’t equal inward energy (gain), a system heats up in order to MAKE them equal. That old superstition was formerly believed to explain why glass greenhouses get warm inside. Sadly, though, the radiative selectivity of glass – it’s transparent to visible light but opaque to infrared –has been found to have nothing to do with heating in a greenhouse. Or anywhere else for that matter. Yet many people still consider the antiquated notion of heating via “radiative equilibrium” as a fact.

    PHYSICS FACT #7: The Earth’s temperature is increasing by an amount that is consistent with predictions, based on the laws of physics and the well known heat-absorbing properties of the excess carbon dioxide

    FACT: The most unbiased and un-tampered-with temperature record, that from satellites, shows no warming trend at all for several years.

    Look at predictions versus actual temperatures below:

    Intergovernmental Panel on Climate Change (IPCC), 2007, p. 675, based on Santer et al, 2003. See also IPCC, 2007, Appendix 9C). Authors added actual temperature data from 1998 to Nov. 2010. Intergovernmental Panel on Climate Change (IPCC), 2007, p. 675, based on Santer et al, 2003. See also IPCC, 2007, Appendix 9C). Authors added actual temperature data from 1998 to Nov. 2010.

    The black line is actual temperature, way lower than predicted.

    PHYSICS FACT #8: Measurements show that night-time temperatures are increasing faster than daytime temperatures, just as physicists predicted. The excess carbon dioxide causes a warmer night-time sky which is the main source of heat at night, but does not affect the brightness of the sun, which is the main source of daytime heat.

    FACT: True physicists are seldom involved in such predictions. IPCC stooges and the like perform them instead.

    And no, a warmer night-time trend has only been observed where the UHI (urban heat island) effect is involved. In other words, the heat-retaining factor is traceable to the cityscape itself, not to CO2.

    PHYSICS FACT #9: Measurements show that the top of the atmosphere is getting colder, just as physicists predicted, because the excess carbon dioxide in the lower atmosphere is blocking the heat from below.

    FACT: As noted above, CO2 doesn’t “block” anything. It releases thermal energy as soon as it absorbs it, and what it emits is of a longer wavelength than it is capable of absorbing again. But a prediction based on theory must ultimately face the facts. Theory has it that IR-interactive gases like carbon dioxide form a radiative blanket, an insulative cover (see #4 above) that makes the lower atmosphere warmer and the upper atmosphere cooler than it would be otherwise. Thus the familiar experience of cooler temperatures as you climb in altitude, a phenomenon called the lapse rate. Theory also has it, then, that an increase of gases like carbon dioxide will cause this thermal discontinuity to increase as well, making the lower atmosphere even warmer and the upper colder still.


    Unfortunately for the theory and those “physicists”, however, this temperature gradient has got nothing to do with so-called greenhouse gases. That’s a fact. Real physicists understand that gravity impacts the atmosphere such that warm air, being lighter, is pushed upward and expands, thereby growing cooler – while cool air, being heavier, compresses as if falls and thereby grows warmer. This necessarily generates a pattern of lower temperature by altitude. Beyond a pressure of 100 millibars, it is a pattern common to every planet.

    The lapse rate has nothing to do with trace gases and everything to do with gravity and pressure.

    PHYSICS FACT #10: Heat-sensing instruments on satellites have measured a reduction in the amount of infrared radiation coming from the atmosphere, at the exact wavelengths predicted by physicists. Anybody who calls themselves a “skeptic” must refute one or more of these physics facts by publishing the extraordinary evidence for their claim. Otherwise, it the word “denier” is appropriate.

    FACT: The earth has cooled since 1998. Near surface air temperature records, corrected for the Urban Heat Island effect (which is mainly nocturnal, expanding of city warming as cities have grown) show that the globe is actually cooling.

    It is basic physics that we all understand: a cooler object radiates less than a warmer object. This includes the frequencies Puckerclust refers to. The reduction he notes, “reduction in the amount of infrared radiation coming from the atmosphere, at the exact wavelengths predicted by physicists” is misrepresented, as he does not mention whether other frequencies have also reduced (which they have). This is in line with what “we” would expect from standard, accepted thermodynamics: if an object cools, it radiates less.

    The reduction (misleadingly) noted by Mr Puckerclust is merely confirmation at a planetary level that a cooler object radiates less thermal energy than a warmer one across the wavelength spectrum. A rather less alarming (and physically correct) picture than Puckerclust has tried to portray.

    • Mike Jowsey on 30/04/2011 at 2:00 pm said:

      This is a very inspired article RC – thanks for the link. Worth reading the original, along with the comments. (esp. Gator)

  4. Richard C (NZ) on 30/04/2011 at 2:03 pm said:

    Naomi Oreskes says it’s “simple”:-

    “The reason is simple: conservation of energy. If you trap more energy in the atmosphere, it has to go somewhere, and one of the places it goes into is weather.”

    Great, now we’re getting somewhere. Some of the “missing heat” has gone “into” the weather, where’s the rest gone?

    Her evidence for CAGW (from the CAGW straw clutchers grab-bag – just make it up as you go along):-

    The harms of global warming will unfold over the next several decades and we do not know exactly what form that will take. But there are already plenty of signs. Spring is coming earlier than it used to.

    Rivers and lakes are warming. Glaciers are shrinking, while glacial lakes are expanding. Permafrost is becoming unstable. Plants and animals are shifting their ranges upwards in terms of both latitude and elevation.

    Oreskes also says there is a credible argument that people are beginning to die from extreme weather events that are probably linked to climate change. In her foreword to Haydn Washington’s and John Cook’s Climate Change Denial, Oreskes points to the Queensland floods – how some commentators were willing to describe them as biblical, yet almost none were willing to make the connection to climate change.

    Yes, scientists have repeatedly emphasised climate is by definition a pattern, and one event does not a pattern make. But she says the Queensland floods are part of a pattern – one that in 2010-11 included devastating floods in China and Pakistan, heat waves and fires in Russia and catastrophic mudslides in Brazil.

    It’s also consistent with what scientists have long predicted – that climate change would lead to an increase in extreme weather events.

    Compelling stuff, her book “Merchants of Doubt” retails for $49.99 (good pulp fiction comes at a price).

    Meanwhile, JoNova is reporting a Stephan Harper survey of 100 West Australians. Some results:-

    A staggering 37% of carbon-based-life-form respondents are keen on reducing carbon in the human body. Perhaps the amputation of an appendage at the end of the leg will be the new way to reduce one’s carbon footprint.

    Equally remarkable is the finding that 44% of respondents wish to eliminate carbon and carbon dioxide from food and drink altogether. Nonplussed are the 28% of respondents who don’t think there is any carbon or carbon dioxide in food and drink in the first place.

    Another alarming finding is that 47% of respondents think carbon dioxide is a pollutant. Marginally less at 44% give poor old carbon, the sixth element of the periodic table (and my personal favourite, since without it we would not exist), the big thumbs down.

    A solid majority of 77% know that carbon dioxide is invisible which is encouraging. Yet, there are still many labouring under the misconception that carbon dioxide is black, grey or white – and in some fanciful imaginings, green, blue, yellow or even purple. Thankfully no polka dots.

    Knowing CO2’s colour is one thing but knowing its concentration in the atmosphere is quite another.

    CO2 comprises less than 1/20th of one percent of the earth’s atmosphere – it is a trace gas. Just 7% of respondents knew that CO2’s concentration was under 1%; a sizeable 44% saying more than 10% concentration and 21% saying CO2 represents more than 50% of the atmosphere – an asphyxiating notion if ever there was one. So it would seem the alarmist media has done a sterling job in creating the perception that CO2 is the dominant player in the earth’s atmosphere.

    One fifth of the population estimates CO2 is 1000 times higher than it is.

    These days we hear that climate change is the animating agent for many things, but it will be news to vulcanologists, seismologists and oceanographers that climate change causes tsunamis, earthquakes and volcanic eruptions. Or so say a disturbingly high percentage of respondents to the survey at 53%, 40% and 37%, respectively.

    • Mike Jowsey on 30/04/2011 at 9:12 pm said:

      Yes, I was particularly amazed at the statistic that 68% of women think that tsunamis are a result of global warming (question 4.b). And I thought girls were meant to be smarter than me.

    • Mike Jowsey on 30/04/2011 at 9:16 pm said:

      I’m obviously too gullible 😉

  5. Andy on 30/04/2011 at 5:07 pm said:

    I am quite surprised too at GR’s comments that the warming is not unprecedented. The only real evidence for this is the Hockey Stick graph. Is this now discredited? Surely not!

    • Clarence on 30/04/2011 at 7:33 pm said:

      Well, even Gareth had his legs whipped out from under him by the admission of Prof Phil Jones (on the BBC) that the Mann & Briffa Hockey Sticks had insufficient evidence of what was happening in the Southern Hemisphere during the Medieval Warming Period.

      This statement was very influential as it was made with legal and PR advice, in response to a question on written notice, at a time when Jones was nervous about the pending enquiries into CRU conduct.

    • Mike Jowsey on 30/04/2011 at 9:21 pm said:

      Surely not the HHS!!! (Holy Hockey Schtick). But, wait – what’s this? OH Noes!!

  6. Andy on 01/05/2011 at 11:42 am said:

    Surely we can distill the argument down to these viewpoints:

    (1) The greenhouse effect theory is wrong. The entire AGW theory rests on this and therefore is wrong.

    (2) The basic greenhouse effect is right. Feedbacks are negligible and possibly negative. Ergo, there is nothing to worry about

    (3) The basic greenhouse effect is right..Feedbacks are positive. There will be significant warming, but it will not be catastrophic.

    (4) The basic greenhouse effect is right..Feedbacks are positive. There will be significant warming, and this will cause “runaway warming” that will have a catastrophic effect on the world’s climate system

    We can argue until the cows comes home about tornadoes, ice sheets, etc etc. Surely we can focus on these viewpoints and present the case for each point of view?

    • Richard C (NZ) on 01/05/2011 at 9:45 pm said:

      I prefer that the argument is distilled even further to remove the latitude for erroneous over simplification e.g. Renowden’s “More CO2 means more heat retained in the system”, Oreskes’ “If you trap more energy in the atmosphere, it has to go somewhere” and Palin’s “CO2 heats the earth”. Each of these viewpoints displays ignorance (or willful distortion) of the physics involved.

      Renowden’s statement is closest to correct physics but he is specifying the wrong gas and fails to specify the system. “More [water vapour] means more heat retained in the [atmospheric] system” would be correct due to the greater atmospheric volume and heat capacity of water vapour vs CO2 (@ 275 K: Water Vapour 5%, 1.859 kJ/kgK vs CO2 0.036%, 0.819 kJ/kgK)

      i.e. The GHG role of CO2 is miniscule .

      Oreskes is clearly out of her depth if she thinks energy is “trapped” in the atmosphere and Palin hasn’t got a clue either if he thinks CO2 “heats” the earth.

      Although the term “greenhouse” is a misnomer, the effect is easily demonstrated e.g. cold nights in a tropical desert location where the air is dry vs warm nights where the air is humid e.g. Singapore. This highlights the fact that water vapour is the major greenhouse gas and without evidence of the AGW prescribed CO2 amplification of atmospheric water vapour (increased atmospheric humidity), AGW is a null hypothesis.

      The argument can be distilled even further if recent scientific findings are taken into account. Miskolczi shows how the overwhelming volume of water on the planet assures that the greenhouse effect is constant and adding more CO2 will not change that (small wonder that his findings have been vilified by “The Team”). See “Hungarian Physicist Dr. Ferenc Miskolczi proves CO2 emissions irrelevant in Earth’s Climate”

      I propose then, that a further distillation of the argument be:-

      1) The greenhouse effect theory in respect to increased atmospheric CO2 amplifying atmospheric water vapour (the IPCC’s positive feedback) is wrong as is the IPCC notion of feedback. The entire AGW theory rests on this and therefore is wrong.

      1a) Empirical atmospheric water vapour levels that would prove (if there was even a glimmer of validity) or disprove the amplification theory are being withheld and are not considered a priority by relevant governmental oversight – why?

      2) The climate system is constantly seeking a state of equilibrium (a constant greenhouse effect) governed by the overwhelming abundance and thermal modulation of water on the planet so there is nothing to worry about.

    • Richard C (NZ) on 01/05/2011 at 9:58 pm said:

      Delete “assures”, insert “ensures”. I’ve just worked an 11 hour shift – not conducive to erudition.

    • Richard C (NZ) on 01/05/2011 at 10:02 pm said:

      Also should be “e.g. Sahara vs Singapore” – I give up

    • Huub Bakker on 01/05/2011 at 10:35 pm said:

      If we are talking heat retained in the atmosphere then you also need to include the latent heat of vapourisation of water as well; the extra heat needed to turn water into water vapour. This adds a one-off figure of about 2400kJ/kg of water evaporated.

      If we assume that water vapour increases by 1%, i.e. from 0.05 kg water/kg dry air to 0.0505 kg water/kg dry air, then this adds 0.0005 kg water/kg dry air x 2400 kJ/kg = 1.2 kJ/kg dry air. To get the same amount of heat retained by simply heating up water and air would require a change in temperature of dT = 1.2 kJ/kg dry air / (0.05 kg water/kg dry air x 1.859 kJ/kg water/K + 1 kg dry air/kg dry air x 1.005 kJ/kg dry air/K) = 1.1 C.

      So adding a very small amount of water vapour has the same effect as raising the air temperature by more than a full degree.

    • Richard C (NZ) on 02/05/2011 at 12:51 am said:


      A) Would not latent heat of vapourization be from solar energy input (SW radiation) – not GHG re-radiation?

      B) That energy is not then able to be retained as heat in already full capacity H2O vapour or CO2 at the values given i.e. the energy changes the state from liquid to vapour but it is not then added as Q to the Q of the GHG gases (assuming they are already at full capacity) but to the residual air volume?

      C) The calculation is for energy requirement – not heat retention (or heat content Q)?

      CO2 has minimal evaporative effect. on the ocean so atmospheric water vapour from evaporation is not due to atmospheric CO2 effects anyway (contrary to AGW). Dr Roy Clark:-

      “Over the ocean, the increase in LWIR flux from CO2 is ‘buried in the noise’ of the
      fluctuations in ocean evaporation from wind and surface temperature variations and changes
      in downward LWIR flux due to fluctuations in humidity, aerosols and cloud cover” (see Introduction)

      I will concede though, that more CO2 means [a little] more heat retained in the [atmospheric] system because although minimal, CO2 does have heat capacity (Gareth Renowden please note my concession).. I do plead Occam’s Razor however

      When I get time I want to present the water vapour situation to Sir Peter Gluckman complete with references to appropriate peer reviewed papers. I’ve already compiled what others have written (no point re-inventing the wheel), it’s just a matter of some additions and sending it.

      What you have just calculated Huub, is energy requirement for an INCREASE in atmospheric water vapour but where is evidence of this increase? We have not had comprehensive atmospheric water vapour data for over 12 years but what data we do have does not support rising levels. See “Latest Water Vapor Evidence Confirms IPCC Climate Models Are Wrong, Global Warming Hypothesis Opposite of Reality”

      As far as I am concerned, water vapour is the focus of the CAGW debate. See “Spencer on water vapor feedback”, “Five Reasons Why Water Vapor Feedback Might Not Be Positive” (contains a link to Spencer – Braswell 2010)

      That is not to say that I subscribe to the feedback notion though.

    • Huub Bakker on 03/05/2011 at 7:15 pm said:


      I can’t say that I was looking any further than the comment about heat retention. I took this to mean the heat content in the air. If that is the case then the latent heat is important. That was really the only intention of my comment.

      If we are talking about air near the Earth’s surface then the latent heat forms part of the heat retention as warm air can pick up water. It doesn’t distinguish between heat that comes from sun, GHGs or anywhere else. If you are talking about air in the upper atmosphere then the latent heat will not form part of the picture because there is no liquid water to evaporate.

    • Richard C (NZ) on 04/05/2011 at 1:20 am said:

      This has got me thinking Huub. My original perspective was SPECIFIC heat of STATIC DRY air where heat content is SENSIBLE heat (my interpretation). Sensible and latent heat are thermoDYNAMiC distinctions relevant to transfers and work in my understanding, considerations of which is ENTHALPY (see below) and you are correct to consider the enthalpy of moist air further highlighting the significant role of water in terms of heat (as opposed to the insignificant role of CO2) but I didn’t think it necessary to consider enthalpy merely to compare heat sinks. I don’t think your calculation uses realistic values though (see below).

      This definition of heat content states:-

      “a thermodynamic quantity equal to the internal energy of a system plus the product of its volume and pressure; “enthalpy is the amount of energy in a system capable of doing mechanical work””

      So you are more correct than I in that respect and my use of Q was also incorrect.

      I do disagree totally with this however (in terms of latency)-

      It doesn’t distinguish between heat that comes from sun, GHGs or anywhere else

      It does, and I think that this is the fundamental physics understanding that is lacking in most AGW arguments. Firstly, ALL of the heat comes from the sun (except the neglected geo-fission) via energy in the form of SW thermal radiation. That radiation energy then manifests as heat energy depending on the characteristics of the material that is intercepted i.e. does it absorb at that wavelength or not. The heating effect therefore depends on material – radiation compatibility. Once the radiative energy is converted to heat, then conduction, convection, evaporative etc processes occur but these are thermodynamic processes (heat transfer – not retention) and it is also then that the energy in the form of heat is able to be retained, The ability of air to retain heat is insignificant compared to water however – hence the calls by Pielke et al to dispense with atmospheric temperature and to move to ocean heat content (OHC) as the relevant metric to measure planetary warming (or cooling as it is now).

      Heating effects are far greater from radiative thermal SW energy that has come from the sun than the re-radiated LWIR energy from GHG’s e.g. solar SW penetrates and heats the ocean (the planet’s greatest heat sink by far) – LWIR does not, it’s effect is confined to some evaporative ability at the surface but it is minor in comparison to solar effect so latency does distinguish between energy (not heat) that comes from the sun or from GHG’s and thus the amount of heat realized (sensible or latent) is determined (bugger all from CO2).

      Only REFLECTED solar SW radiation retains the original heating effect; once re-emitted and scattered the wavelength of radiation lengthens and the intensity reduces i.e. the heating ability is degraded.

      On reflection I also retract my concession to Gareth Renowden because I see a major flaw in his statement “More CO2 means more heat retained in the system”, .

      Heat retention relies on there being material present that has the CAPACITY to actually retain heat i.e. heat sinks, space being virtually devoid of material is also devoid of heat. The potential maximum amount of heat that a material (substance, liquid, gas vapour) will retain at specified combinations of temperature and pressure are the specific heat CAPACITIES in units of kJ/kgK. The heat CAPACITY of the ocean relegates the atmosphere to total insignificance, ratio about 4000 : 1. But retention also relies on there being continued temperature (molecular excitation) to sustain the retention.

      In the case of atmosphere (static consideration, the DRY air has a specific heat CAPACITY at whatever temperature and pressure (1.005 kJ/kg.K @ 0 C, 1.293 kg/m3)

      That DRY CAPACITY is the total of all the constituent gases, the relevant two being H2O vapour (1 – 5%, 1.859 kJ/kgK @ 275 K) and CO2 (0.036%, 0.819 kJ/kgK @ 275 K).

      The consideration of specific enthalpy of moist and humid air in the AGW/climate change debate becomes crucial not for the large daily fluctuations but for the small long-term global humidity changes (i.e. what is the actual WV composition of the atmosphere at various latitudes and altitudes and is there increase or decrease?). It is this data that we MUST have access to but is being withheld at present. It is not necessary though, to consider enthalpy when comparing planetary heat sink capacity in my understanding.

      From Engineering Toolbox:-

      Moist air is a mixture of dry air and water vapor. In atmospheric air, water vapor content varies from 0 to 3% by mass. The enthalpy of moist and humid air includes the

      * enthalpy of the dry air – the sensible heat – and
      * the enthalpy of the evaporated water – the latent heat

      Specific enthalpy – h – (J/kg, Btu/lb) of moist air is defined as the total enthalpy (J, Btu) of the dry air and the water vapor mixture – per unit mass (kg, lb) of moist air.

      But to assume 0.05 kg water/kg dry air is unrealistic I think because the temperature would be 40 C (see graph)

      0.01 @ about 15 C would be more realistic surely, or have I got this wrong?

      In the case of ocean (static consideration): the sea water has a specific heat CAPACITY at 0 C atm pressure of 3985 J kg−1 K−1.

      So the ocean – air heat capacity ratio is 3985 : 1.005. This highlights why consideration of atmospheric heat and alarm over atmospheric temperature is just plain silly.

      That’s heat CAPACITY, now heat retention or CONTENT which is determined by measuring temperature pressure volume etc and selecting the appropriate value from specific CAPACITY tables.

      It does not necessarily follow that “More CO2 means more heat retained in the system” (Renowden’s contention) because the addition is (according to Miskolczi) very possibly offset by water vapour reduction (modulation) in the case of atmosphere. The AGW case for CO2 heating the ocean is just not possible given the lack of heating effect of LWIR on water.

      Renowden would have to say “More CO2 means more WV retained in the atmosphere and therefore more heat retained in the [atmospheric] system IF temperatures rise or are maintained at high levels” to correctly state the AGW case but he studiously avoids the WV role (just having more CO2 capacity is not enough, there must be more WV and sustained temperature). The case can be disproved by either the empirical observation of declining heat content (atmosphere and ocean) AND/OR static or declining WV levels. I think the case is being lost on both counts.

      These metrics are critical to the assumptions and models in papers such as Stephen Swartze “Heat Capacity, Time Constant and Sensitivity of Earth’s Climate System” 2007 which attempts to create empirical models that constrain the GCM’s.

      A Google account reqd to view the shared Google Doc.

      Swartze only found 0.7 K estimated rise in GMST attributed to GHG’s (even if it were possible) from pre industrial times to the then present 2007 which fell short of the 2 K threshold for “dangerous anthropogenic interference with the climate system” as defined by Hansen et al. That threshold is no closer now and the recent flat OHC trend upsets the GHG forcing assumptions in that paper at least where there is already large uncertainties in the calcs..

    • Richard C (NZ) on 04/05/2011 at 7:41 am said:

      Basically, a heat sink comparison between the nominal heat sink values of dry air with the heat sink values of WV.

      Addition or reduction of either CO2 or WV in the atmosphere must change the relative proportions of all the other constituents I would have thought.

    • Huub Bakker on 05/05/2011 at 8:52 am said:


      Takes a while to read through your entire comment but I can short-circuit part of it by making the point that adding any CO2 to the atmosphere will LOWER the specific heat capacity of the system. That is for the simple reason that, at around 0.79 kJ/kg/K, the specific heat of CO2 is lower than that of air as a whole, about 1.0 kJ/kg/K. Add any CO2 and you will REDUCE the ability of the air to retain heat. Adding water vapour, on the other hand, will increase the specific heat capacity of the air because it has a higher specific heat capacity, at about 1.7 kJ/kg/K.

      Does that make your analysis more interesting? 🙂

    • You make this sound non-controversial, Huub. But does not this fact, by itself, falsify the proposition that the greenhouse effect might dangerously heat the global environment, much less that it might even run out of control? How could it have been overlooked by professional scientists? They say constantly that increased CO2 heats the atmosphere. Or the oceans, perhaps. Or are they changing the argument, so solar radiation now heats the oceans directly, without recourse to the greenhouse effect?

      Do you have a reference to the specific heats? On second thoughts, you would probably just refer me to a science text book, or an encyclopaedia. The kind of thing where you look up details of the Periodic Table or check the speed of light — right? I’ll Google it!

    • Richard C (NZ) on 05/05/2011 at 9:03 pm said:

      Yes you’ve made it more interesting Huub – I disagree because we need to consider density.

      Case 1) For increased density of a set volume (mass increase):

      Increased CO2 and WV will both increase the heat capacity of the set volume,

      The entire atm volume remains the same and it’s heat capacity is increased. But what would cause density to increase (there’s no constraint)?

      Case 2a) For same density of a set volume (mass – no change):

      Increased CO2 will lower the heat capacity of a set volume.

      The entire atm volume is increased by the gases displaced by the CO2 but the volume displaced has a higher heat capacity than it would be if it had CO2 in it. What then is the nett effect? [I haven’t got the time to do this calc at present]

      Case 2b) For same density of a set volume (mass – no change):

      Increased WV will increase the heat capacity of a set volume/

      Tthe entire atm volume is increased by the gases displaced by the WV but the volume displaced has a lower heat capacity than it would be if it had WV in it. What then is the nett effect? [I haven’t got the time to do this calc either at present]

      In both cases the entire atm mass is increased so total potential heat capacity must increase but that potential is only realized by the requisite temperature and pressure conditions.This ignores Renowden’s oxygen depletion issue which decreases total atm mass although the nett effect of that is probably still increased potential heat capacity.

      I’m not convinced by your argument Huub but the picture is a little clearer regardless of whoever is on the right track and my head doesn’t hurt as much.

      Your move.

    • Richard C (NZ) on 07/05/2011 at 1:42 pm said:

      Huub, I think Gareth Renowden is confusing potential heat capacity with actual measured heat his statement “More CO2 means more heat retained in the system”

      It does not necessarily follow that just because there is more CO2 in the atmosphere that more heat will actually be retained; it is conditional on the requisite temperature and pressure conditions . This is proven by the missing hot spot in the critical pressure region about 400 – 200 hPa at 8 – 12 km altitude above the tropics

      If the required temperature is not being observed, he’s wrong.

  7. Andy on 04/05/2011 at 9:58 am said:

    Gareth has some more evidence, in the form of increased heating nights.
    This is consistent with greenhouse warming. It is also consistent with increased cloud cover and increased UHI effects. Have these latter been ruled out?

    The links to Skeptical Science are worth following. The comments below each post often open up more questions.

    • Richard C (NZ) on 04/05/2011 at 9:43 pm said:

      Notice that the warm night trend is down since 1999 and the graph stops at 2003, what has happened in the 7 years since then? Typical of Gareth he is still dining out on the 80’s and 90’s warming but he turns a blind eye to the trends of the last decade.

      The atmospheric carbon vs oxygen graph is interesting. Huub has got me thinking a great deal about the physics of Gareth’s statement:-

      “More CO2 means more heat retained in the system”.

      I think that it does not conform to AGW (or physics) and should be something like:-

      “More CO2 means more WV retained in the atmosphere and therefore more heat retained in the [atmospheric] system IF temperatures rise or are maintained at high levels”

      AGW is then disproved by either the empirical observation of declining heat content (atmosphere and ocean) AND/OR static or declining WV levels (starting to look that way on both counts).

      But how do we know what is happening to the long-term composition (the heat sink) of 1 cubic km of atmosphere at altitude 10 km say? My reasoning is:-

      1) Start with the composition of the atmosphere at initial satellite era levels (dry air plus WV, what was that composition?) .

      2) Add CO2 increase and WV changes over the satellite era and adjust all the other constituents accordingly.

      Position 2) is the atmospheric carbon vs oxygen situation (not just oxygen). This article linked is a commentary on the study that would probably be the original source of the data Gareth has presented:-

      “Atmospheric Oxygen Levels Fall As Carbon Dioxide Rises”

      Read more:

      From the lead scientist of the study (Dr. Ralph Keeling) :-

      It is roughly true that the oxygen depletion is equivalent to a displacement by carbon dioxide. But it is not exactly true. First, some of the carbon dioxide produced has been absorbed by the oceans. This process involves inorganic chemical reactions which have no effect on O2. Second, the O2:C combustion ratio of a fossil-fuel depends on the hydrogen content. The ratio varies from about 1.2 for coal, 1.45 for liquid fuels, and 2.0 for natural gas. Taking these factors together, we are losing nearly three O2 molecules for each CO2 molecule that accumulates in the air.

      Long-term addition of CO2, WV or anything else means (I think) that a proportion of all the other constituents are displaced from the 1 km^3 volume so that the atmosphere increases in total (TOA rises) but if there is also depletion of constituents e.g. oxygen, the situation becomes very complicated and my head starts to hurt.

      And what if WV is now declining as indications are (but the comprehensive data is being withheld)?

      Apart from all that, consideration of the atmosphere is a total waste of time because the ocean – atmosphere heat sink ratio is 4000 :1 i.e. it is what happens in the ocean that determines long-term warming/cooling trends and contrary to some of the more bizarre AGW reasoning, CO2 does not heat the ocean.

    • Andy on 04/05/2011 at 9:54 pm said:

      I really don’t buy this heating nights argument. Anyone who has spent time in a city at night knows that it retains heat.

      We know that there is a lot of UHI contamination in the temperature record.

      Has anyone factored this out on the night versus day measurements?

    • Huub Bakker on 05/05/2011 at 9:32 am said:

      I seem to recall a study done recently in the US looking at the temperature trends for weather stations that showed that the night-heating effect is only seen in urban or contaminated weather stations, not rural. I think it was a statement made by Anthony Watts in one of this posts (with link presumably) but I can’t be sure.

      Anyway, this would support the idea that the night-heating effect is only due to UHI (including for weather stations that are supposed to be rural but are contaminated by buildings, tar seal etc.)

    • Andy on 05/05/2011 at 9:53 am said:

      I found one link on C3 Headlines on this nighttime heating topic

      Of course, this doesn’t conclusively “prove” anything, but then science is, or should not be, about “proving” things, but be about creating falsifiable statements

  8. Con Michael on 02/04/2012 at 8:44 pm said:

    According to the rigors of scientific discipline,a theory is not worthy of any consideration unless it implies the sort of evidence that would prove it wrong.Predictions based on the theory are checked against the facts.How many anomalous results are sufficient to invalidate a proposition?To paraphrase Einstein…..a mere one.Recent decades are replete with failed global warming predictions.Ergo the AGW theory has been discredited.

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