Incredulity, Credulity and the Carbon Cycle

Incredulity, in the face of startling claims, is a natural human reaction and is right and proper.

When I first heard the news about the detection on 14th September 2015 of the gravitational waves from two colliding black holes by the LIGO observatories I was incredulous. Not because I had any reason to disagree with the predictions of Albert Einstein that such waves should exist, rather it was my incredulity that humans had managed to detect such a small change in space-time, much smaller than the size of a proton.

How, I pondered, was the ‘noise’ from random vibrations filtered out? I had to do some studying, and discovered the amazing engineering feats used to isolate this noise.

What is not right and proper is to claim that personal incredulity equates to an error in the claims made. If I perpetuate my incredulity by failing to ask any questions, then it’s I who is culpable.

And if I were to ask questions then simply ignore the answers, and keep repeating my incredulity, who is to blame? If the answers have been sufficient to satisfy everyone skilled in the relevant art, how can a non expert claim to dispute this?

Incredulity is a favoured tactic of many who dispute scientific findings in many areas, and global warming is not immune from the clinically incredulous.

The sadly departed Professor David Mackay gives an example in his book Sustainable Energy Without the Hot Air (available online):

The burning of fossil fuels is the principal reason why CO2 concentrations have gone up. This is a fact, but, hang on: I hear a persistent buzzing noise coming from a bunch of climate-change inactivists. What are they saying? Here’s Dominic Lawson, a columnist from the Independent:  

“The burning of fossil fuels sends about seven gigatons of CO2 per year into the atmosphere, which sounds like a lot. Yet the biosphere and the oceans send about 1900 gigatons and 36000 gigatons of CO2 per year into the atmosphere – … one reason why some of us are sceptical about the emphasis put on the role of human fuel-burning in the greenhouse gas effect. Reducing man-made CO2 emissions is megalomania, exaggerating man’s significance. Politicians can’t change the weather.”

Now I have a lot of time for scepticism, and not everything that sceptics say is a crock of manure – but irresponsible journalism like Dominic Lawson’s deserves a good flushing.

Mackay goes on to explain Lawson’s error:

The first problem with Lawson’s offering is that all three numbers that he mentions (seven, 1900, and 36000) are wrong! The correct numbers are 26, 440, and 330. Leaving these errors to one side, let’s address Lawson’s main point, the relative smallness of man-made emissions. Yes, natural flows of CO2 are larger than the additional flow we switched on 200 years ago when we started burning fossil fuels in earnest. But it is terribly misleading to quantify only the large natural flows into the atmosphere, failing to mention the almost exactly equal flows out of the atmosphere back into the biosphere and the oceans. The point is that these natural flows in and out of the atmosphere have been almost exactly in balance for millenia. So it’s not relevant at all that these natural flows are larger than human emissions. The natural flows cancelled themselves out. So the natural flows, large though they were, left the concentration of CO2 in the atmosphere and ocean constant, over the last few thousand years.

Burning fossil fuels, in contrast, creates a new flow of carbon that, though small, is not cancelled.

I offer this example in some detail as an exemplar of the problem often faced in confronting incredulity.

It is natural that people will often struggle with numbers, especially large abstract sounding numbers. It is easy to get confused when trying to interpret numbers. It does not help that in Dominic Lawson’s case he is ideologically primed to see a ‘gotcha’, where none exists.

Incredulity, such as Lawson’s, is perfectly OK when initially confronting a claim that one is sceptical of; we cannot all be informed on every topic. But why then not pick up the phone, or email a Professor with skills in the particular art, to get them to sort out your confusion?  Or even, read a book, or browse the internet? But of course, Dominic Lawson, like so many others suffers from a syndrome that  many have identified. Charles Darwin noted in The Descent of Man:

“Ignorance more frequently begets confidence than does knowledge: it is those who know little, not those who know much, who so positively assert that this or that problem will never be solved by science.”

It is this failure to display any intellectual curiosity which is unforgivable in those in positions of influence, such as journalists or politicians.

However, the incredulity has a twin brother, its mirror image: credulity. And I want to take an example that also involves the carbon cycle,.

In a politically charged subject, or one where there is a topic close to one’s heart, it is very easy to uncritically accept a piece of evidence or argument. To be, in the technical sense, a victim of confirmation bias.

I have been a vegetarian since 1977, and I like the idea of organic farming, preferably local and fresh. So I have been reading Graham Harvey’s book Grass Fed Nation. I have had the pleasure of meeting Graham, as he was presenting a play he had written which was performed in Stroud. He is a passionate and sincere advocate for his ideas on regenerative farming, and I am sure that much of what he says makes sense to farmers.

The recently reported research from Germany of a 75% decline in insect numbers is deeply worrying, and many are pointing the finger at modern farming and land-use methods.

However, I found something in amongst Harvey’s interesting book that made me incredulous, on the question of carbon.

Harvey presents the argument that, firstly, we can’t do anything to reduce carbon emissions from industry etc., but that secondly, no need to worry because the soils can take up all the annual emissions with ease; and further, that all of extra carbon in the industrial era could be absorbed in soils over coming years.

He relies a lot on Savory’s work, famed for his visionary but contentious TED talk. But he also references other work that makes similar claims.

I would be lying if I said there was not a part of me that wanted this to be true. I was willing it on. But I couldn’t stop myself … I just had to track down the evidence. Being an ex-scientist, I always like to go back to the source, and find a paper, or failing that (because of paywalls), a trusted source that summarises the literature.

Talk about party pooper, but I cannot find any such credible evidence for Harvey’s claim.

I think the error in Harvey’s thinking is to confuse the equilibrium capacity of the soils with their ability to take up more, every year, for decades.

I think it is also a inability to deal with numbers. If you multiply A, B and C together, but then take the highest possible ranges for A, B and C you can easily reach a result which is hugely in error. Overestimate the realistic land that can be addressed; and the carbon dioxide sequestration rate; and the time till saturation/ equilibrium is reached … and it is quite easy to overestimate the product of these by a factor of 100 or more.

Savory is suggesting that over a period of 3 or 4 decades you can draw down the whole of the anthropogenic amount that has accumulated (which is nearly 2000 gigatonnes of carbon dioxide), whereas a realistic assessment (e.g. is suggesting a figure of 14 gigatonnes of carbon dioxide (more than 100 times less) is possible in the 2020-2050 timeframe.

There are many complex processes at work in the whole carbon cycle – the biological, chemical and geological processes covering every kind of cycle, with flows of carbon into and out of the carbon sinks. Despite this complexity, and despite the large flows of carbon (as we saw in the Lawson case), atmospheric levels had remained stable for a long time in the pre-industrial era (at 280 parts per million).  The Earth system as a whole was in equilibrium.

The deep oceans have by far the greatest carbon reservoir, so a ‘plausibility argument’ could go along the lines of: the upper ocean will absorb extra CO2 and then pass it to the deep ocean. Problem solved! But this hope was dashed by Revelle and others in the 1950s, when it was shown that the upper-to-lower ocean processes are really quite slow.

I always come back to the Keeling Curve, which reveals an inexorable rise in CO2 concentrations in the atmosphere since 1958 (and we can extend the curve further back using ice core data). And the additional CO2 humans started to put into the atmosphere since the start of the industrial revolution (mid-19th century, let us say) was not, as far as I can see, magically soaked up by soils in the pre-industrial-farming days of the mid-20th century, when presumably traditional farming methods pertained.

FCRN explored Savory’s methods and claims, and find that despite decades of trying, he has not demonstrated that his methods work.  Savory’s case is very weak, and he ends up (in his exchanges with FCRN) almost discounting science; saying his methods are not susceptible to scientific investigations. A nice cop-out there.

In an attempt to find some science to back himself up, Savory referenced Gattinger, but that doesn’t hold up either. Track down Gattinger et al’s work  and it reveals that soil organic carbon could (on average, with a large spread) capture 0.4GtC/year (nowhere near annual anthropogenic emissions of 10GtC), and if it cannot keep up with annual emissions, forget soaking up the many decades of historical emissions (the 50% of these that persists for a very long time in the atmosphere).

It is interesting what we see here.

An example of ‘incredulity’ from Lawson, who gets carbon flows mixed up with net carbon flow, and an example of ‘credulity’ from Harvey where he puts too much stock in the equilibrium capacity of carbon in the soil, and assumes this means soils can keep soaking up carbon almost without limit. Both seem to struggle with basic arithmetic.

Incredulity in the face of startling claims is a good initial response to startling claims, but should be the starting point for engaging one’s intellectual curiosity, not as a perpetual excuse for confirming one’s bias; a kind of obdurate ignorance.

And neither should hopes invested in the future be a reason for credulous acceptance of claims, however plausible on face value.

It’s boring I know – not letting either one’s hopes or prejudices hold sway – but maths, logic and scientific evidence are the true friends here.

Maths is a great leveller.


(c) Richard W. Erskine, 2017


Filed under Climate Science, Essay, Uncategorized

8 responses to “Incredulity, Credulity and the Carbon Cycle

  1. - Julian Jones

    Thank you for this posting Richard; there is a paucity of science here.

    Incredulity defines limits of comprehension and a number of rigid creeds collide over the SOCS issue; traditional vs technocratic knowledges; vegetarianism vs omnivorism; scarcity vs abundance; corporate vs greater social interest, etc.

    The reason for introducing Graham was for sensitive discussion; local interest and effort in this vital subject is longstanding. Our first comprehensive film on this predates the Savory TED talk (1 – 2009). My work as an agri-environmental auditor (2 – slide 2, Dairy Farmer 1982) required understanding natural nutrient produced with solar energy and carbon cycling. I only studied this at school (Carbon Cycle, Water Cycle etc) and since on farms; it seems we are moving progressively away from sound complete science.

    Rivers Trusts Chief Executive, Arlin Rickard, asked at their 2012 Exeter conference, ‘What has happened to our soil-science in the UK?’ (3) We should also ask, ‘What has happened to our agriculture?’ Maybe only now is the weak science underpinning this beginning to be exposed (4)(5). This seems to have impinged on Climate Science; not just the SOCS (chemicals prevent this) but other crucial factors and soil thermal issues too.

    I assumed sequestration and persistent accumulation of atmospheric C as terrestrial and aquatic humus to be well understood and evidenced. I have not seen Monbiot & FCRN state this; they may not have practical experience or grasp the primary science. The Calvin Cycle as I understand it, as in the dark phase of photosynthesis – enabling microbial metabolic gains of atmospheric C as humus, with endothermic gains ?

    I work with the practical reality of these processes in reed beds for wastewater treatment eg (6 – page 11, para 2) and for decades (7 – 1991, @ 34.30 mins) as the resultant C humus clogging from nutrient loading is a persistent and terminally major problem in constructed wetlands; it stops them working (8) but only if they are constructed from aggregates (which most are). There is an obvious answer … not yet in the literature.

    Prof R Lal sees SOCS as a cost-effective “bridge to the future” that buys us time in which to develop alternative energy options (9). He also states the wetland C sequestration in rice paddy already significantly contributes to a 20% sequestration of China’s total 1994 CO2 emissions (10). I have little experience with rice; but with phragmites reeds another (perennial) grass, whose powerful SOCS functionality would be severely compromised if butchered in the way most farmers graze pastures; Savory & Harvey appear totally correct in their advice. A big error here seems to be assuming that if something isn’t in the literature it cannot be true; similar kept us believing Earth was flat for centuries.

    Persistent accumulation of atmospheric C as humus in soil is well evidenced in trad. agric., both European and especially in Pre Colombian Amerindian. Such ‘Terra Preta’ soils are equipped with thick carbon­ rich topsoils that persist centuries after their abandon­ment (11). This requires the use of bio-char; according to Cornell University (12), can persist for hundreds and thousands of years can be considered a permanent carbon sink.

    My preference is to replace the bio-char with natural manures and composts. Ruminants have a fantastic unique ability to convert solar cellulose into prodigious volumes of nutrient and carbon; with just the right microbial context, see more in this film we made about trad. European agric (13). Perpetual and limitless SOCS here should thus be possible, on all farmland and much more.

    I have posted an essay for the Gloscan blog to discuss further.


    1 2 slide 2, Dairy Farmer 1982 3 4 5 6 page 11, para 2 7 8 9 10 11'Terra_Preta'_phenomenon_A_model_for_sustainable_agriculture_in_the_humid_tropics/links/53e531890cf25d674e9895bd/The-Terra-Preta-phenomenon-A-model-for-sustainable-agriculture-in-the-humid-tropics.pdf 12 13


    • Educated people from the Greeks onwards never thought the Earth was anything other than round. I agree that soil science is challenging, but that is not a reason to extrapolate from incomplete science to ‘strong’ statements on what soil carbon can deliver. I bought and read Graham Harvey’s book; I did not imagine what I read. I believe his views are honourably held, but that does not make them right. Soil carbon and a move away from intensive farming is something I 100% support and believe is hugely important. My issue is only with exaggerated claims that soil carbon can on its own account, single handedly solve man-made global warming. It is really that simple (my objection). See which I believe shows what different solutions can contribute. Soil carbon is one amongst many.

      Liked by 1 person

  2. power21visitor

    Thank you Richard – is a great step in the right direction.

    I hope you would also have an issue with those people & organizations who have not noted this clearly significant issue in the vital efforts to moderate atmospheric CO2 and global temperatures ?


    • I am indeed. I have no problem with champions for different solutions, such as Jeremy Leggett for Solar Energy, Elon Musk for EVs and Battery Storage, Dale Vince for Wind Power, and so on; Soil Carbon included. But I am also a fan of the late Professor David Mackay, who stressed the need for maths. I think it is unhelpful to allow one’s championing of a solution to tempt exaggeration of its contribution, and the dismissing of others. I like the recognition that we will need multiple solutions which are all needed to crack global warming, and Project Drawdown is a good example of that, including quantification of the contributions which is essential for planning and deployment.


  3. Pingback: Ending the Climate Solution Wars: A Climate Solutions Taxonomy | EssaysConcerning

  4. Pingback: Matt Ridley shares his ignorance of climate science (again) | EssaysConcerning

  5. “… the debate about the role of agricultural soils in climate mitigation is eroding scientific credibility”

    Academia slowly catching up with community led science :

    Film, 46 mins, 2009, Soil Carbon Farming in Australia :


  6. Of particular importance to soil & climate science :
    ‘Peer review: a flawed process at the heart of science and journals’


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