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The Latest Pre-Bunked Denialist Letter in Lieu of Real Science

Posted on 1 December 2012 by dana1981

For climate denialists, the preferred route by which to air their grievances about global warming is not via the scientific peer-review process, but rather through opinion letters published in the mainstream media.  The reasons are obvious — a paper submitted to a peer-reviewed scientific journal must pass a fairly rigorous review by scientific experts, whereas a letter published in a newspaper does not undergo any expert review, and thus can contain whatever unsubstantiated nonsensical arguments the contrarians think the general public will believe.

The latest such letter was published in the Financial Post, authored by Tom Harris (who is best known for grossly misinforming Carleton University students about climate change in a Climate and Earth Science class he should never have been teaching).  Harris convinced 125 mostly similarly unqualified individuals to sign the letter, including Anthony Watts, Joe Bastardi, Christopher Monckton, Nils-Axel Mörner, Oliver Manuel, Fritz Vahrenholt, Tim Ball, William Happer, Richard Cohen, Syun-Ichi Akasofu, Don Easterbrook, Joe D'AleoIvar Giaever, Cliff Ollier, Fred Singer, Ole Humlum, Jan-Erik Solheim...the list of individuals with no climate expertise or with a history of being wrong on climate issues goes on and on and on.

Of course any scientific assertions should be evaluated based on their own merit, regardless of who makes them.  As is always the case with these sorts of opinion letters, the Financial Post letter contains little more than a Gish Gallop of false, unsupported assertions.  Fortunately we have already debunked most of them at Skeptical Science, so dispelling these zombie myths once more is a relatively simple task.

Denialists Pre-Bunked on Continued Global Warming

The main assertion, made several times in the letter, is a repeat of the myth that global warming stopped 16 years ago.  This is one of the few arguments in the letter that has a shred of supporting evidence, as the contrarians claim:

"The U.K. Met Office recently released data showing that there has been no statistically significant global warming for almost 16 years."

This assertion quite clearly refers to the misleading Daily Mail article which was pre-bunked by Nuccitelli et al. (2012).  While the measured global surface warming over the past 16 years is not statistically significant (0.047±0.128°C per decade), the central value is positive, meaning the average surface temperature has most likely warmed over this period.  More importantly, rising global surface temperatures represent a very small percentage of overall global warming, most of which is borne out through the warming of the world's oceans (Figure 1).  As Nuccitelli et al. (2012) showed, this global warming has continued unabated (Figure 2).

where is warming going

Figure 1: Components of  global warming for the period 1993 to 2003 calculated from IPCC AR4


Fig 1

Figure 2: Land, atmosphere, and ice heating (red), 0-700 meter OHC increase (light blue), 700-2,000 meter OHC increase (dark blue).  From Nuccitelli et al. (2012).

Denialists Pre-Bunked on Accurate Global Warming Projections

The climate denialsts also picked a very bad time to claim that global warming projections are exaggerated:

"Rigorous analysis of unbiased observational data does not support the projections of future global warming predicted by computer models now proven to exaggerate warming and its effects."

The timing is very poor because Rahmstorf et al. (2012) just pre-bunked this claim by verifying the accuracy of the global surface temperature projections made by the climate models used in the IPCC report (Figure 3).

RFC12 Fig 1

Figure 3: Observed annual global temperature, unadjusted (pink) and adjusted for short-term variations due to solar variability, volcanoes and ENSO (red) as in Foster and Rahmstorf (2011).  12-month running averages are shown as well as linear trend lines, and compared to the scenarios of the IPCC (blue range and lines from the 2001 report, green from the 2007 report).  Projections are aligned in the graph so that they start (in 1990 and 2000, respectively) on the linear trend line of the (adjusted) observational data.

Denialists Pre-Bunked on Solar Non-Cooling

Several climate contrarians who have predicted impending global cooling signed the letter, which contained the following assertion:

"Some scientists point out that near-term natural cooling, linked to variations in solar output, is also a distinct possibility."

Feulner & Rahmstorf (2010) examined the impact on global warming if the sun fell into a grand minimum.  They found that average global surface temperature would be diminished by no more than 0.3°C, which would only offset a tiny fraction of human-caused global warming (Figure 4).

Figure 4: Global mean temperature anomalies 1900 to 2100 relative to the period 1961 to 1990 for the A2 scenario. The red line represents temperature change for current solar levels, the blue line represents temperature change at Maunder Minimum levels. Observed temperatures from NASA GISS until 2010 are also shown (black line) (Feulner & Rahmstorf 2010).

And how have those contrarian global cooling predictions (by Akasofu and Easterbrook, among others) fared thus far?  Unlike the IPCC, not well at all (Figure 5).

1976-2011 all predictions

Figure 5:  Various best estimate global temperature predictions evaluated in the 'Lessons from Past Climate Predictions' series vs. GISTEMP (red).  The warmer colors are generally mainstream climate science predictions, while the cooler colors are generally contrarian predictions.

Denialists Wrong on Extreme Weather

The letter steals from the Roger Pielke Jr. obfuscation playbook, trying to argue that climate change is not linked to extreme weather because thus far there is no clear link between human-caused global warming and economic losses from extreme weather.  While the scientific evidence indicates that the intensity and/or frequency of many types of extreme weather is increasing due to human-caused global warming, there is not yet a clear trend in economic damage caused by extreme weather, when increases in population are taken into account.  This may be in part to improving technology making our buildings and infrastructure more resistant to extreme weather.

Note the careful wording in the letter (emphasis added):

"The U.N.’s own Intergovernmental Panel on Climate Change says in its Special Report on Extreme Weather (2012) that there is “an absence of an attributable climate change signal” in trends in extreme weather losses to date."

However, the letter also asserts:

"The incidence and severity of extreme weather has not increased."

This is incorrect.  For example, the same IPCC report on extreme weather cited by the contrarians states:

"It is likely that anthropogenic influences have led to warming of extreme daily minimum and maximum temperatures at the global scale. There is medium confidence that anthropogenic influences have contributed to intensification of extreme precipitation at the global scale. It is likely that there has been an anthropogenic influence on increasing extreme coastal high water due to an increase in mean sea level."

As noted above, there is a large and growing body of scientific literature finding not only that the incidence and severity of many types of extreme weather has increased, but also that human-caused global warming is the cause.

Denialists' Sandy Strawman

The letter is specifically addressed to United Nations Secretary-General H.E. Ban Ki-Moon, and the contrarians falsely accuse him of "making unsupportable claims that human influences caused [Hurricane Sandy]."  In reality, Ban Ki-Moon did not say climate change caused Hurricane Sandy, he said:

"...extreme weather due to climate change is the new normal."

This is true — as discussed above, climate change is increasing the frequency and/or intensity of many types of extreme weather.  Human-caused global warming also amplified the impacts of Hurricane Sandy.

Wrong, Unsupported, and Misguided Denialists

Ultimately the denialists advise that we should not try to mitigate global warming by reducing greenhouse gas emissions, but that we should instead focus our efforts on adapting to "all dangerous climatic events however caused."  While adaptation is a necessary step due to the impacts from already-caused climate change, adaptation alone is an insufficient response.  As we frequently quote Lonnie Thompson saying about the consequences of human-caused climate change,

"The only question is how much we will mitigate, adapt, and suffer."

We simply cannot adapt to the probable catastrophic consequences of a continued business-as-usual path.  If these contrarians want to make a convincing case that the consequences will not be bad and adaptation is sufficient, they need to make the case in the peer-reviewed scientific literature, as mainstream climate scientists do.  It would be foolish to be convinced by a letter published by a list of non-experts in a newspaper, full of false, long-debunked, and unsubstantiated assertions.  The public deserve better from scientists.

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Comments 51 to 59 out of 59:

  1. To learn more about Brian G Valentine and his views on climate change, check out DeSmog Blog’s profile of him by clicking here.
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  2. Brian Valentine @49 tries to baffle us with bullshit. The most important piece of bullshit in his armoury is the pretense that global warming is only predicted by zero dimensional models - ie, models that take as inputs only the globally averaged insolation, the globally averaged albedo, and the globally averaged means surface temperature; and from these and the Stefan-botlzmann law calculates in increase in surface temperature due to the greenhouse effect. He spends much verbiage pretending that because these very simplified models used almost solely for educational purposes have (surprise, surprise) certain simplifications, that therefore they are false and the theory of the greenhouse effect fails. One could almost imagine that there are no models which divide the Earth's surface into 2x2 degree sections, with multiple atmospheric layers, with absorption and reflection of solar radiation calculated for each each layer seperately, and so on. One would almost imagine that these models (let's call them coupled Ocean Atmosphere global circulation models) do not predict the same general outcome as the simplified models - and that scientists are restricted in making predictions about the greenhouse effect to only the simplified models. So, armed with this pretense, Valentine pretends to refute models designed to teach people with only a grade 10 level of education in science the core concepts of the greenhouse effect; and pretends therefore to have refuted the actual science. For his next trick, no doubt, he will refute the science of ballistics by pointing out the existence of air resistance. Sadly, Valentine fails in his efforts even against the cut down science he will admit as evidence against his views. He argues that the Earth does not have a constant temperature, and that therefore the 33 degree K approximation for the total greenhouse effect from simplified models is in error. What he does not mention is that a body with uneven surface temperatures radiates more energy for a given mean surface temperatures than one with an even temperature. So, yes, the assumption of equal temperatures introduces an inaccuracy,but that inaccuracy underestimates the magnitude of the greenhouse effect. If we allowed uneven surface temperatures, the result would be a larger than 33 K greenhouse effect; not a smaller one. He then argues that the Stefan-Boltzmann law cannot be applied to the globe as a single unit. Thereby, he claims to refute the notion that greenhouse gases reduce the energy radiated to space relative to what would have been radiated without their presence. Of course, if you look at the radiation from particular places, at particular times you will see something like this: This may be difficult for Valentine, but the essential point is that the area under the approx 295 K approximation is the energy that would have been radiated to space at that location and time where it not for atmospheric absorption, most notably the large notch at a wavenumber of 15 cm-1. Of course, the actual energy radiated (ie, the area under the observed curve) is less than the surface radiation, and hence, the presence of CO2 in the atmosphere at that time and location has reduced the energy radiated to space at that time and location. It turns out, from multiple observations, that this is true at nearly all times and locations on the Earth's surface. Consequently, the average of the reduced energy radiated to space from all those times and locations represents a large global shortfall in energy relative to what would have occurred without the presence of the greenhouse effect. That, of course, is something Valentine does not want you to know, or think about under any circumstances. For if you do know it, and think about it you will know that the presence of an atmospheric greenhouse effect has been observed and known about from direct observation since 1970. And Valentine hides this from himself by criticizing simplified models as though they were all of climate science; and never, under any circumstances developing a complex model such as those developed by genuine climate scientists. And he hopes and prays that you will never cotton on, even if he manages to prove that a simplified model is, well, simplified; he does not thereby prove that more accurate models will not show the same basic effect shown in the simplified model. So, in the end, there is only one thing you really need to no about Valentine. He is a charlatan.
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  3. I can't write much now, and will not be able to for some days. Thank you for calling me names, Tom, it shows to me what I am guilty of, and is a good lesson for me. Obviously your graph shows what happens when one looks out a window fogged by water (ha just a joking analogy), what is absorbed is re-radiated at longer wavelenghts still. If there were observational evidence of the "greenhouse effect" and I deny it - then you have called me the wrong name. Valentine is not a "charlatan" - he is "insane"
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  4. "Hansen describes it as radiation increasing from higher levels in the atmosphere to maintain an equilibrium with (outer space), Ramanatan does not. " Hansen's explanation is the outcome of the Ramanathan model (we are talking about Ramanathan and Coakley here?). There is no contradiction. "that the oceans are not in equilibrium with the atmosphere," Do you think this is news to climate modellers? So lets see - the Radiative Transfer Equations at the core of greenhouse theory successfully predict the temperature structure of the atmosphere and the spectrum that will be observed when viewed from both surface of the planet looking up, and from the top of atmosphere looking down. The model can do this for any planet (taking proper account of rotation speed). By contrast, you have so far not offered an experiment that the physics cannot explain. So what appears more likely - you have found a flaw in the physics? Or that you have failed to fully understand the physics?
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  5. "what is absorbed is re-radiated at longer wavelenghts still." Are these longer wavelengths somehow undetectable?
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  6. "what is absorbed is re-radiated at longer wavelenghts still." Molecules have discrete vibrational energy levels and can not radiate at any wavelength they wish. Any undergrad in chemistry or physics could tell. And don't forget that Kirchhoff and Plank laws apply here.
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  7. And further to venus versus moon... the question of meaningful use of averages depends of on what you want to use them for. The difference between dark and light side temperatures are extreme because it doesnt have an atmosphere. Venus does and surface temperature is very uniform (thanks to atmospheric greenhouse effect) despite its slow rotation.
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  8. re Brian Valentine @53: The "insults" are far less than those deserved by a PhD in physics who pretends not to understand the role of simplified models in pedagogy; and bases their criticisms of a theory solely on those models rather than the actual theory. A scientist, acting in good faith, who intended to criticize the theory of the greenhouse effect would start by showing how, if the greenhouse effect they predict does not exist, Line by Line radiation models achieve such stunning matches with observation as those achieved by the Fu-Liou model: For those who can't count all those dots, that 134,862 comparisons between the model and observations with a very tight fit. Further, those model/observation comparisons were made over a wide range of conditions, so they are robust: What is more, a scientist acting in good faith would, if they doubt a theory and wish to suggest that observations outside the range of current instruments refute that theory, design an experiment to test that hypothesis. They would not glibly assert their untested hypothesis in public forums as if their unsupported word carries more weight than literally hundreds of thousands of observations. The telling fact that shows the various charlatans such as Valentine are just that is that they do not conduct the research which, according to them, would quickly disprove the existence of the greenhouse effect by observations. Nor do they build global models from the ground up, encoding basic physics and known initial conditions to see whether their theory holds water outside of simplified examples. Climate scientists do both of the above because they actually believe their theory, and expect useful results. In contrast, the "scientists" of Valentines ilk believe their theory so firmly that they are afraid to test it. But that does not slow down their efforts to distribute it to an (they hope) un-discerning public at every opportunity. So, what of Valentines claim that the energy missing from absorption in the CO2 band reappears at longer wavelengths. Well, the Line By Line models say no: The green region is the radiation to space at the top of the atmosphere. The red region is the additional radiation to space if the surface had the same temperature and there was no atmosphere. Clearly in the longer wavelengths (and hence smaller wavenumbers), emission to space is also reduced relative to that which occurs at the surface. Ergo that those wavelengths cannot be making up the shortfall at a wavenumber of 15 cm-1. You will also note the rapid fall of of power emitted per wave number as wave number decreases, which means the shortfall simply cannot be made up at still lower wavenumbers (longer wavelengths) than those shown in the model.
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    Moderator Response: [TD] Somebody really, really should put the content of this comment in a Skeptical Science Argument post! (Okay, omitting some sentences and paraphrasing others.)
  9. Superb comment Tom - very nicely showing details that Valentine avoids in his verbiage in #49, notably that CO2 inhibits energy loss from Earth, and so that energy has to go somewhere. Now Valentine expects us to somehow have missed observing all the energy scattered by CO2 molecules escaping at some hitherto undefined "longer" (#53) wavelength. Surely, as apparently a PhD physicist, Valentine is aware of the skill with which humans are able to observe electromagnetic radiation, its emission and absorbtion at huge ranges of wavelengths, from gamma rays, through visible light, to radio. The emission and absorbtion of radiation, and our ability to spectroscopically measure this is the cornerstone of astrophysics, allowing us to understand the chemical composition of stars, the presence of planets, the expansion of the Universe and myriad other things without travelling vast distances. Geoscientists can send a rover to Mars and do chemical analyses of rocks (ChemCam), using similar techniques, and there are an astonishing range of earth-based applications of this knowledge, including most of telecommunications. Earth observation satellites are constantly measuring emissions from Earth at all manner of wavelengths for a wide range of applications. Maybe Valentine thinks the energy scattered by CO2 escapes at secret wavelengths (#53), known only to him. Maybe he thinks that CO2 in Earth's atmosphere is unique in the Universe in its response to electromagnetic radiation. I rather think he is fundamentally, and hopelessly wrong. Especially as we observe the Earth is gaining energy as expected.
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