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Sunday, November 24, 2013

Denier weirdness: defending the indefensible Murry Salby at WUWT

Sou | 6:50 PM Go to the first of 5 comments. Add a comment

In this article I'm going to show how silly Murry Salby's "hypotheses" are (as archived here).  There's a lot of "wrong" with Salby's efforts but two things stand out the most in my view:

  • Murry Salby is a greenhouse effect denier and
  • Murry Salby thinks billions of tonnes of carbon can disappear off the face of the earth by magic.

Following on from my last article, Anthony Watts has posted a few diagrams of Murry Salby's, provided not by Murry but by Christopher Monckton.  I don't know who wrote the text.  I'll take the opportunity Anthony Watts and Christopher Monckton have provided to do what HotWhopper does - demolish disinformation.

This will be a dull article, I'm afraid.  Murry Salby's slide series ranks with this "stupid" list I compiled some months back.  It's mind-numbingly stupid - not earning the "stupid and funny" ranking of "OMG it's insects".

A few points at the outset.  In the WUWT article, there is no provenance provided for any of the diagrams. No sources are cited.  The information might just as well have come from St Joseph's Kindergarten as from a reputable scientific source.  Where I've been able to do so I've added information from reliable sources.  Where the Murry drawing looks to be meaningless I've said so.

(The material is so sloppy that I'm surprised Murry Salby managed to get as far as he did in academia.  However these drawings were provided by Christopher Monckton to Anthony Watts, neither of whom have any links to academia.  It may be that Murry Salby himself would have provided data sources - but he seems to have disappeared.)

Ratio of 13C to 12C is dropping as expected  

Slide One on the right is from Murry Salby and purports to show 13C as a proportion of 12C in the atmosphere, from 1845 to 1990. The chart on the left is from data at CDIAC / Scripps data for Mauna Loa from 1981 to 2008, showing the 13C:12C ratio is dropping. (As always, click the image for a larger view.)

Data Source: CDIAC/Scripps CO2 Program (left) Salby/Unknown/WUWT (right)

As Murry says, 13C is declining as a proportion of 12C.  This is as it should be as more fossil fuel carbon enters the atmosphere. Since this is as expected I've not bothered to try to find data going back in time - which possibly comes from ice core data.  True to form Murry doesn't give any clue to his data sources - ever.

As you'll see later, even though Murry shows this evidence supporting the fact that it's mainly burning of fossil fuels that's caused atmospheric CO2 to rise, he brushes it and all the other evidence aside, and says it "could be" something else - without giving a hint of what that "something else" could possibly be.

Explanation of trend from CDIAC:

The 13C isotope is stable and heavier than the normal form of carbon (12C), and plants tend to selectively assimilate the lighter isotopes during the photosynthetic process. This results in the following features of the 13C/12C ratio in the atmosphere:
  1. a seasonal cycle occurs with the heavier isotope at relatively high concentrations during the summer, as plants selectively remove the lighter isotope from the atmosphere, and
  2. a general decrease with time, as more fossil carbon (which originally was plant material, and consequently biased toward the lighter isotope) is injected into the atmosphere from the combustion of fossil fuels.
Additionally, about 95% of fossil-fuel carbon emissions are from the Northern Hemisphere, and there is a 6-12 month time lag before this material is transported by the atmosphere to the various stations in the Southern Hemisphere. The seasonal cycle reverses and its amplitude decreases in the Southern Hemisphere, where the seasons are opposite those in the Northern Hemisphere and there is much less land area to support a terrestrial biosphere.

Explanation of trend from Murray Salby / Monckton / WUWT

There is about one molecule of 13C in every 100 molecules of CO2, the great majority being 12C. As CO2 concentration increases, the fraction of 13C in the atmosphere decreases – the alleged smoking gun, fingerprint or signature of anthropogenic emission: for the CO2 added by anthropogenic emissions is leaner in 13C than the atmosphere.
However, anthropogenic CO2 emissions of order 5 Gte yr–1 are two orders of magnitude smaller than natural sources and sinks of order 150 5 Gte yr–1. If some of the natural sources are also leaner in [13]CO2 than the atmosphere, as many are, all bets are off. The decline in atmospheric [13]CO2 may not be of anthropogenic origin after all. In truth, only one component in the CO2 budget is known with any certainty: human emission.
(Note: two of the CO2's in the second WUWT para are probably meant to be 13CO2 - I've amended the text accordingly.)

Conclusion - Murry Salby is denying chemistry

Murry Salby is already trying to argue that there "might be" some hidden unexplained sources of CO2 that have the isotopic signature identical to plants and fossil fuels.  Either that or he is already rejecting the chemistry that burning fossil fuels releases carbon dioxide in this equation:

hydrocarbon + oxygen ---> CO2 + H2O

He does not offer any explanation of what this hidden unknown source might be.  The only explanation he gives for why whatever unknown it may be is suddenly behaving so differently to how it behaved in the past, is that the temperature has gone up!  Nor is he offering any explanation of what happened to the CO2 released when fossil fuels are burnt if the extra 12C is coming from another source.

This is very basic stuff that Murry is denying.  It's not rocket science.  All the evidence points to the fact that adding CO2 from burning long-buried fossil fuels is leading to an accumulation of CO2 in the air and carbon on the surface (in the oceans and biomass).

Seasonal impact on atmospheric CO2

Murry Salby makes much of the fact that there is a seasonal influence on the levels of atmospheric CO2. What he neglects to do is explain it.

As stated in the excerpt from CDIAC above, in summer plants grow and use up CO2.  There is a lot more land and a lot more plants in the northern hemisphere so the effect is much more marked there.  This is expected behaviour and is trivial knowledge even for a scientist who is unfamiliar with biology as Murry Salby seems to be.

The animation below shows this seasonal influence very elegantly.  If you skip to toward the end, it also shows how atmospheric CO2 is higher than at any time in the past 800,000 years - and maybe higher than at any time in the past 15 million years.

Sources of CO2

Murry Salby shows the slide below.  He gives no inkling as to the source or what exactly it is meant to represent, other than the scale at the bottom and saying "CO2 is emitted and absorbed at the surface. In the atmosphere it is inert. It is thus well mixed, but recent observations have shown small variations in concentration, greatest in the unindustrial tropics. "

Source: Unknown except for WUWT

Not good enough Murry! The above could be a chart of anything at all.  It might be a summer time chart or a winter time chart.  It could be taken when there were major fires burning in Africa (like in 2004).  It could be of CO2 at the surface or in the mid-troposphere (unlikely). Or it could be a chart of something else altogether.

Thing is, the amount of emissions from coal, for example, can be measured and monitored.  There is a wide array of organisations monitoring and reporting energy use and fossil fuel combustion and vegetation, as well as monitoring CO2 in the atmosphere itself.  Murry Salby would know this but decides that he prefers his shonky un-named, un-sourced drawings and vague waving of his hands.

For example, below is a map showing CO2 concentration from the Japan Meteorological Agency (JMA)
The global mean concentration of carbon dioxide (CO2) in 2011 was the highest on record [Sou: at the time]. Annual mean concentrations in 2011 were particularly high in parts of Europe, parts of East Asia and in the eastern USA
Source: JMA
JMA includes in the chart fluxes from fossil fuel use, fluxes from the ocean and fluxes from vegetation.  It describes the chart as:
The CO2 distribution maps shown below are made from model calculations using an inversion method based on data reported to the WDCGG (World Data Centre for Greenhouse Gases) operated by JMA.

For some neat animations of how CO2 travels around the world in various heights in the troposphere, the AIRS website has some movies.

The following video from the Vulcan Project shows CO2 emissions in the United States.

Murry Salby has a mission to deny that humans are causing harm by digging up and burning carbon that has been sequestered for millions of years.  What does he think?  Does he really and truly think that putting billions of tonnes of added carbon into circulation year after year after year won't have any consequences?

Murry moves from "we don't know" to "I know but won't say"

Murry takes a giant leap after waving his arms and muttering "we don't know this" and "we don't know that" about things that many people do know.  He takes a giant leap and claims that all the rise in CO2 is caused by "naturally caused component" - which he claims is "derived solely from temperature and soil moisture changes".

Thing is, he jumps right over what has caused temperatures to rise so quickly or what has caused his supposed "soil moisture changes".  He ignores these things.  He unhitches the horse and puts the cart right up front.  But the cart won't be going anywhere all on its lonesome.  It needs the horse to pull it.

Here's one example of one of the silliest drawings I've come across in a pile of silly drawings at WUWT:

Source: Salby/Unknown/WUWT

Accompanied by one of the silliest bits of text that I've read:
The circulation-dependent naturally-caused component in atmospheric CO2 concentration (blue above), derived solely from temperature and soil moisture changes, coincides with the total CO2 concentration (green). 
"Circulation-dependent naturally-caused component" - what is that?  And "derived solely from temperature and soil moisture changes"?  Logic fail!

Let's see now.  We've added more than twice as much CO2 to the air than is needed to explain the rise in atmospheric CO2 that Murry shows in his chart - which, by the way, is pretty old, isn't it.

About 55% of emissions are being absorbed by the oceans (30%) and plants (25%) and he wants to argue something other than fossil fuel burning is emitting billions of tonnes of CO2 each year by attributing the rise to "a naturally-caused component"!

Murry has already shown that by measuring 13C:12C ratios, all the extra CO2 in the air came from plant sources.  And it's not as if the number of plants on earth have decreased hugely and sent all their carbon into the air.  On the contrary, plants are absorbing more CO2 not less.  (Whatever happened to "CO2 is plant food"?)

And where does Murry think that all the carbon disappeared to from burning billions of tonnes of sequestered ancient plant material?  Into space?  Did the lizard men squirrel it away on their space ships and transport it to Mars?  No.  I'm sure Sarcastic Rover would have told us if they'd done that.

More meaningless shonky drawings

Murry finishes off with some equally silly fake drawings.  For example this one, in which he seems to think that global surface temperature should follow the trend of atmospheric CO2 precisely.  And to think that he used to be a scientist.  And a scientist who was supposed to specialise in climate.  How the mighty have fallen.

Source: Salby/Unknown/WUWT

How many things can you see wrong with this chart?
  1. There are no data sources.  The data could come from inside Murry's head for all we know.
  2. What native emission? It talks about "CO2 from Native Emission (Temperature Induced)" - but there is nothing on earth that is a net emitter of CO2 in such quantities except for us digging up and burning long buried hydrocarbon.  The two biggest carbon reservoirs on earth, oceans and plants, are absorbing much more than they are emitting. They are absorbing just over half of the carbon from human activities.  
  3. Meaningless scales. It plots CO2 and temperature in a meaningless fashion.  All you have to do is change the scale on the left and it will change the look of the entire chart.

Murry's two biggest "wrongs" out of many

If I had to pick one giant flaw in Murry's nonsense I'd find it hard to choose between the following two:
  • Denying the science of the greenhouse effect: His topsy turvy "temperature-induced" claim - he doesn't attempt to explain what has caused earth to warm up.  He hasn't mentioned the greenhouse effect.  He glosses over the fact that it's the increase in greenhouse gases that have "induced" the temperature.  He's putting the cart before the horse.

  • Disappearing fossil fuel carbon by magic: His feeble attempt to avoid the fact that burning fossil fuels have added hugely to the carbon in the short term carbon cycle.  We've shifted carbon that's been lying dormant underground, sequestered by the long term carbon cycle, and moved it into the air and the oceans and the biosphere.  He points to the irrefutable evidence that the carbon in the air is from plant sources, consistent with the burning of fossil fuels - and then rejects the evidence for no reason at all.

In the WUWT comments it's been pointed out that Murry fails with ice cores, too.  I didn't bother looking into that aspect but they are probably right.  He's failed everything else.

From the WUWT comments

A smattering of comments from WUWT - for your entertainment (archived here).

Greg Goodman says something sensible (for a change):
November 23, 2013 at 5:55 am
I really wonder when Salby is going to publish something (even just an internet article) where we can properly asses what he’s got to say.
C. Monkton’s snapshots of Salby’s presentation … it’s all getting rather farcical.

CodeTech says, somewhat weirdly:
November 23, 2013 at 5:57 am
So, just for my own summary, what we are seeing is:
1. A clear reduction in the CO2 rise during a known cooler time (early 90s)
2. A clear increase in the CO2 rise during a known warmer time (1998)
3. A reduction in the percentage of “human fingerprint” CO2 of 13C
So the logical conclusion is that something other than human input is the cause of the increase of atmospheric CO2 levels, and that something is affected by temperature.
Surely this is GOOD news to the alarmists!

johnmarshall says he doesn't believe anything that has even a whiff of science.  And anyway "it's not CO2":
November 23, 2013 at 6:07 am
Who cares? CO2 does NOT drive temperature/climate. There is no empirical data demonstrating that CO2 drives climate, climate models do but model output is not proof of anything only the ability of the programmer. Present model runs do NOT agree with reality so all FAIL.

gopal panicker says "it's the rain":
November 23, 2013 at 6:40 am
CO2 is absorbed and emitted at the surface’…what about rain ?…CO2 is fairly soluble in water…with the tiny volume of a cloud droplet…and the very high ratio of surface to volume..all raindrops should be saturated with CO2…IMHO this should be the main mechanism for removal of CO2 from the atmosphere…and the reason why CO2 has not risen as fast as emissions…assuming all the other processes remain the same

James V asks for help because he's going to be outed as a denier and says (excerpt):
November 23, 2013 at 8:18 am
So someone please help a layman out here because my sister wants to out me as a denier at the thanksgiving table. 

Appropriately named kingdube decides to have it both ways and says it's not just rising temperatures that cause CO2 to rise, falling temperatures will cause CO2 to go up sharply too (excerpt):
November 23, 2013 at 1:49 pm
I expect it reasonable to predict that as the Earth cools, atmospheric CO2 will spike sharply from natural causes. (Of course the alarmists will then argue, when this occurs, that poor Mother Nature can no longer choke-down the anthropogenic emission – she has had her fill from us. But that will be a misinterpretation of this natural process.) Further explanation below:

Andres Valencia bows and scrapes to the lord and wrongly says temperature drives rising CO2 and "it's all a big plot by the nefarious IPCC":
November 23, 2013 at 4:20 pm
Thanks, Christopher, Lord Monckton. Very good article.
You write that “the CO2 concentration response to the time-integral of temperature very closely tracks the measured changes in CO2 concentration, suggesting the possibility that the former may cause the latter.”. Well, yes!
The IPCC got it backwards because they were looking to corroborate a hypothesis and forgetting to try and find ways to falsify it. The corroboration proved to be weak and elusive, the falsification, much stronger, was at hand but unseen. Confirmation bias or malice?

Paul Schauble quotes Jquip who says "it's not fossil fuels it's animals eating corn" or is it ethanol?:
November 23, 2013 at 5:09 pm
Jquip says
>the only manner in which I can attempt to justify the 13C depletion is IFF this can be reflected in >animal preferences for C4/CAM plants as a food source: Corn, sugar cane, etc.
Could corn used to make ethanol for motor fuels make a difference?

Edim says the temperature (bi?)cycle will pump all the CO2 out of the air until it disappears completely:
November 23, 2013 at 5:39 pm
The seasonal global temperature cycle is driving the annual change in CO2. It acts as a pump, which flow is temperature dependent. The airborne fraction will decrease further with the cooling and at some point it will reach zero, in spite of the record human emissions.


  1. 1) I think Monckton got the slides from Salby, from the talk in Edinburgh.
    Scottish Skeptic showed some of the same slides.

    2) Salby did quite credible atmospheric physics for decades, culminating in a well-regarded book in 1996. But after that, he never again collaborated with faculty colleagues at either CU or MQ, and research productivity and citation counts slid, to the point that almost nothing submitted after 2002 got much interest from others.
    (I've collected the ~60 publications from 1990 onward.) I.e., I think the science is OK, but few people cared about it, unlike the well-cited earlier works.

    3) Most of his 2012 book is ~same as the credible atmospheric physics of the earlier book. The problem is the 10-20 pages of bogus climate science, including at lest 13 SkS bad arguments, references to one of the worst papers:
    Robinson, A, Baliunas, S, Soon, W, and Z Robinson, 1998: Environmental effects of increased atmospheric carbon dioxide. Med Sent, 3, 171– 178, reliance on Lamb(1965) temperature sketch.
    From the SkS fixed list: SkS # 5, 6, 7, 11, 20, 26, 29, 38, 58, 90, 107, 188, 189.

    4) But there was no trace of the silly CO2/ice-core ideas before July 2011.

  2. Yes, I've started to get people on my blog both defending Salby and claiming that they can prove the rise in atmospheric CO2 is natural. As you can imagine, such discussions don't end well.

  3. The "Sources of CO"-map is form the SCIAMACHY satellite.

    It is explained on p 2867 in Schneising et al. Long-term analysis of carbon dioxide and methane column-averaged mole fractions retrieved from SCIAMACHY, Atmos. Chem. Phys., 11, 2863–2880, 2011, as follows:

    The resulting annual composite averages of atmospheric XCO2 after quality filtering for the years 2003–2009 are shown in Fig. 2 exhibiting similar patterns for all years superposed by a steady quite homogeneous increase with time. A significant part of the CO2 spatial variations shown in Fig. 2 results from the irregular sampling of the SCIAMACHY XCO2. For example, the mid- and high-latitudes of the Northern Hemisphere are strongly weighted towards late spring, summer, and early autumn, where CO2 is known to be much lower than for the (true) yearly average. This uneven weighting is due to the significantly higher cloud cover in winter but also because of larger solar zenith angles and snow coverage. As a result, most of the mid- and high-latitude measurements in winter are automatically filtered out by the implemented quality filtering scheme.

    So it does not show what Salby wants us to think it shows.

  4. Lars, there's a rather entertaining exchange between Eli Rabett and ScottishSceptic on ScottishSceptic's site in which Eli essentially points out the same as you have. I won't link to it as Sou may not thank me for that, but you could probably find it if you wanted to do so - it's his post that reports on Salby's lecture in Edinburgh.


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