Friday, 16 October 2009

Back to Climate Change

Jon and I back in the office this morning, me after 10 hours door to door from Istanbul, and Jon 44 hours from Adelaide!!

Checking emails and a very interesting one from Prof. Keith Atkinson, former Director of Camborne School of Mines:

Following our lunch, you may care to place this contribution on your blog and I'll watch for the brickbats!

I read the climate debate with interest and tend to agree with those who have taken your South African contributer to task. I thought you gave a balanced set of answers but reading his responses I can see that Galileo was right -"...we all tend to see what we expect to find". Regarding Ian Plimer, I first came across him when I was writing "Ore Deposit Geology" with Richard Edwards and therefore when I saw his article "Climate Change, a geologist's view" in Materials World, March 2009, I wrote to him as I thought his was an interesting view on the subject. He replied that his book, which you cite, had become a best seller in Australia and he was touring the country on book signings – not normally associated with academic authors! I have yet to read his book so cannot comment on the veracity of its findings, but I am struck by the emphasis that some of your contributors place on peer review. I agree that peer review is the best we have but what concerns me is peer review cannot always assess the original data. Remember the falsified Indian fossils saga? Furthermore I wonder how many reviewers check/rework the results and, of course, unless you have access to the programs and the models into which the data are fed you have no control over the predictions. Like you, I have experience of models produced by well recognized people which, when examined in detail, i.e. line by line, had some fundamental errors with far reaching, and erroneous, consequences. Have we all forgotten the Club of Rome and the Limits to Growth debates of the late 60's early 70's and the dire predictions for global mineral resources based on "models"? For those who have, we shouldn't have any mercury, tin etc by now!

Having got that off my chest I'd just like to make some observations based on geological data. Global temperatures have varied, often dramatically and over short time frames, throughout Geological Time. We could, of course, talk of the climate in "Britain" during the Cretaceous, or Triassic, as being much hotter than today but really that would have little bearing on today's position. Therefore we can look at the Holocene, and perhaps just the last 10,000 years and the Flandrian Transgression. As you know, the last major Glaciation ended about that time and sea level, globally, was over 100 metres below Present Day. This means that over the last 10,000 years sea level globally has been rising by an average of 1metre per hundred years (10mm p.a.). This, I believe, is equivalent to the most severe of the current climate model predictions for the next hundred years. Coming more up to date, the longest tidal gauge records for Europe suggest a small, but steady, rise since records began (c1800), with an acceleration over the last half century to about 2mm per year. For comparison, it has been calculated that around 8,000 years Before Present some 18 trillion metric tonnes per annum of glacially derived water was being added to the oceans and the global sea level was rising by about 50 mm per year. We have to talk of global because, with isostatic adjustment due to offloading ice, some land was rising and sea level in those areas was falling relatively. About 7,500 years ago the Climatic Optimum occurred when global temperatures may have been as much as 4degrees C higher than today. There is plenty of published work containing figures for specific areas. For example if we consider the North Sea between 8000 and 3000BP sea level rose from 55metres below present to 6 metres below present (therefore from 3000BP to today the average rise has been 2mm p.a.- the accelerated rate quoted above ).

What does all this tell us? Very significant global temperature variations, with concomitant sea level rises, have been occurring long before humans tramped the Earth and also while they have tramped the Earth but before they used massive amounts of fossil fuel sources (Oil, Coal) to contribute Carbon Dioxide to the atmosphere. Without going into the debate over the universality and accuracy of the temperature readings which you mention, as global temperatures are rising the big question - which I think you have already posed - is to what extent is man contributing? There is plenty of evidence to show it has happened in the past without "help" from man. In any scientific experiment you'd want a "control", unfortunately in this debate there isn't one, i.e. would this temperature rise (and sea level rise) have occurred anyway? This is where you need to examine the models very carefully - how do you establish the base level? how do you calculate the 'normal' annual effect (ie without man's influence), are there any missing variables, etc etc?

Finally, if we look at glacial/interglacial precedents, based on Milankovitch Cycles and previous interglacial stages, the Earth should be going towards another Ice Age, after the Climatic Optimum quoted above (you make reference to this in one of your comments to your South African contributor) so if man is having a marked effect what we may be seeing is a delay imposed on the next Ice Age!!

I think you have chosen a great topic for your future Conference let us hope that there are people there who can provide stimulating papers whatever their stance.

Incidentally, you may remember that in 1997 in conjunction with the University of Plymouth and the Plymouth Marine Laboratory I tried to establish a Centre for Climate Impact Forecasting (CCLIF) in the South West of England to help Insurance Companies, Banks etc understand the likely effects of Climate Change – and we failed to get funding support. How times have changed!!

All the best to you and Barbara and everyone associated with Minerals Engineering International.


  1. From Stephan Harrison, University of Exeter:

    Of course climate change has occurred in the past without humans, but that doesn't mean that humans can't be
    causing climate change now! People got hurt in accidents before
    cars were invented but cars still hurt people. We know that human
    C02 is causing warming, that's why we do formal attribution studies. I'm afraid Keith is wrong about the Holocene Optimum. Temperatures were higher then than now but only in the high latitudes of the Northern hemisphere and only in summer. The warming then doesn't begin to compare with what we see at the present. In addition, we are also not going to see renewed glaciation for thousands of years. Even without human AGW
    orbital forcing won't give us another ice age for at least 50-100ka. I
    would also point out that Plimer's book is full of nonsense. He made
    graphs up, misrepresents the science, misrepresent and misunderstands many of the scientific papers he references etc.

    The obvious question is this: why doesn't Plimer publish his results
    in the scientific literature? If he's right then he will win the
    Nobel Prize for Physics by showing that we have all got Greenhouse
    Effect etc wrong. The prize is worth $1m and he'd be the most famous
    scientist in the world. The obvious reason is that he knows he's
    talking nonsense. His book was originally published by an almost
    unknown small-scale publisher. I imagine nobody else would touch it. There's no doubt it's made him famous (and probably lots of money)...maybe that's why he wrote it.

    In the end, the overwhelming majority of informed scientists accept AGW. The only way you are going to falsify it is to show that the laws of physics are wrong.

  2. From Robert Odle Principal Engineer at Dreeser-Rand, USA (via LinkedIn):

    As I understand it, much of the planet is currently in a five year cooling cycle, which was not predicted by current models. It is obviously difficult from my chair to know if this statement is correct, but hearing it and not hearing any counter arguments by those that advocate global warming, or the new tone downed phrase, global change, makes me suspicious.

    See this link

    He does an excellent job challenging the "global warming" advocates.

    I have been a reluctant by-in to global warming since I never saw a "pro" list on the good things that come from global warming, only a con list. Nothing is all good or bad. An correlations between variable were always presented as CO2 is the cause and this is the effect instead of exploring the alternative explanations such as both variables could be an effect of increased solar activity (sun spots, etc.) In short, the articles on the subject of global warming never struck me as good science, they sounded more like a good sermon, a religious approach.

    My current conclusion is that fear of global warming is being used as yet another way to tax us via industry. Another way for us to tax ourselves into economic oblivion.

    A much more important topic is becoming energy independent. That focus for America would lead us in many cases to the same actions, wind power for example, improved and more efficient (smarter) energy grids, nuclear power, etc., but without the distractions of what appears increasingly to be bad science.

  3. stephan harrison17 October 2009 at 17:36

    Hi Robert.
    No, the planet is not in a cooling can't look at ternds shorter than about 10 years anyway, but these all show an increase in warming. The idea that scientists are fixated by C02 is not true. We also look at the influence on the climate of other factors (volcanic activity, natural variability, orbital forcing, Galactic Cosmic Ray effects, solar cycles, sunspots etc). None of these explain the recent warming. It's been known for nearly 200 years that there is a greenhouse effect; it's been 150 years since we knew that C02 was a greenhouse gas and about 110 years since the first estimates were made of the temperature increase associated with doubling C02. We know that the increase in C02 MUST be having a warming trend. Solar activity is at an historic low at the moment and doesn't explain the stratospheric cooling nor the nighttime warming that is occurring (both a predicted response to GHG forcing).

    It's also not true that the models didn't predict 5 year trends...they're not supposed to do this anyway! As usual, the 'tax' issue is trotted out. Just because you don't like the idea of global warming (for political, ideological, tax reasons, or because you think it's a socialist plot) doesn't negate the science.

    Stephan Harrison

  4. From Andrew Cuthbert Director - Global Marketing at FLSmidth Minerals, USA

    Have you seen this article

  5. stephan harrison18 October 2009 at 11:05

    Hi Andrew
    Yes I had seen it. a couple of points:
    First, much of the discussion only concerns 11 years of data (1998-2009). Under AGW T over that period should have risen by about 0.2C periods and flat (or even declining temperatures) are not unusual and have happened before (in 1987-1996). The reason for this is that over this sort of time period, the noise in the data (natural variability) is the same magnitude as the's only over longer time periods that the signal overwhelms the noise. In addition, it's a bit like a warm spell in April versus a cold snap in May. When that happens do you claim that the sun doesn't drive seasonal temperature change?

    Second, it's not even clear whether this cooling is happening. HadCru data shows a flattening trend (but with no cooling)whilst GISS shows warming over the period. In this data set (which is preferred to HadCru because of data coverage issues) the past ten 10 year trends have ALL been between 0.17 to 0.34 C warming per decade, which is close to or above the expected (modelled) trend.

    In other words, don't always believe what journalists say!

  6. Ok, what are the good effects of global warming, besides delaying the next ice age.

  7. stephan harrison19 October 2009 at 09:45

    Well there are some laboratory studies showing an increased yield of certain plants with elevated C02, but the consensus (as far as I understand it....I'm a Quaternary scientist) seems to be that C02 isn't the limiting factor. Also, fewer people will die during cold snaps. Overall, however, the impacts of climate change will be negative, for us and ecosystems.

  8. I really appreciate your contributions to this discussion Stephan, and I sincerely hope that you might consider presenting a paper at the Climate Change and the Minerals Industry ’11 conference in Falmouth (low emission travel for you!).

    I still have my doubts, but I am not suggesting that your assertions are wrong- I just feel that the complexities are so enormous that there may be factors that we have missed or do not know about. And I still worry about the quality of the input data to the models (particularly average annual temperatures).

    Simple question- in your opinion is global warming entirely anthropogenic, or do other factors contribute? If the latter, what is your gut feeling on the percentage contribution from humans?

  9. stephan harrison19 October 2009 at 11:06

    Thanks. You are right about the complexities but look at it this way. The sea is enormously complex but we can still predict certain aspects of its behaviour (tides) while having no predictive understanding of its small scale behaviour (future wave heights, sand movements in waves etc). The same thing with the climate. We know that when you change the boundary conditions of a complex system like the climate that allows us to predict the long-term evolution of the system.

    While we have no ability to predict next month's rainfall, we can say that if you force the climate (by increasing solar activity or increasing GHG etc) then the climate will respond. We know that solar activity isn't driving present warming and other drivers are either flat or declining. It's only the enormous increase in GHG that fit. Basic radiative physics also shows that when we increase GHG the atmosphere MUST respond by warming. Of course, other things might work againist it in the short term (reducing solar activity during the 11 year cycle, or volcanic activity) but eventually the climate will warm.

    The input data to the models doesn't include average annual temperature. The models are developed from simple energy balance models....temperature is an output rather than input.

    The warming we've seen since the 1970s is mostly the result of GHG present the rather flatter T are also forced by declining solar and natural variability. Finally, there will always be uncertainty in science, but we regularly make policy decisions despite this (eg links between smoking and lung cancer etc).

  10. Thanka again Stephan. Although I have doubts, I have said all along that unless we know for sure that global warming is not anthropogenic then we must assume that it is and policy decisions must be made to combat it.

    Realistically though, do you think anything substantial will come out of Copenhagen in December? Global ban on the motor car for instance?!

  11. stephan harrison19 October 2009 at 11:39

    I'm sure that there will be lots of policy ideas and aspirations from Copenhagen but few hard decisions or targets. The targets that we are aiming for seem to be unrealistic (in terms of their likely outcomes). 2C warming is likely to create 'dangerous climate change' for instance. I'm working with several governments on this at the moment, and that's what I'm telling them.

    I don't think there will be a ban on cars! There should be huge incentives to buy low carbon or zero carbon cars though.

  12. I'm sure there won't be a ban on cars!! It would be a wonderful world without them though.

  13. From Prof.Keith Atkinson (by email):

    Hi Barry
    I see the debate is "heating up". In response to Stephan's comments on mine perhaps you could place the following;

    Hi Stephan, thanks for you comments on my piece. I am old enough not to become upset if I am told I'm wrong. My statement about the 4degreesC being global (rather that restricted to the higher latitudes of the Northern Hemisphere) was based on data from the USGS so I guess they must have got it wrong. As you know, I'm not a Climate Scientist.
    Regarding your car analogy; man could not have been killed by cars before they were invented so it is not analogous to CO2 which was having global affects before Man started using energy the way he has for the last 2 centuries. Using you car analogy for human induced global warming - cars have been killing people for just over a century but are they significantly "forcing" global deaths?
    Regarding Ian Plimer you will notice I haven't read his book so I cannot comment.
    Finally I notice someone, anonymously, has commented on models and causation. You must know of the "classic" old statistical chestnut where Sales of Ice Creams are plotted against Accidents to feet caused by lawnmowers. A complete correlation of course but not a causative one!
    Keep up the good work and please heed Barry's request for a paper.



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