Category Archives: agw

On not talking about agw

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I thought this was interesting, especially this quote:

“I very specifically avoided that whole area [climate change] for two reasons. The first is that I thought I could create a compelling enough sense of urgency without going into that topic, and the second reason is that I had worked with this enough in various life settings to discover that there are people on both sides of that story that hold very strong beliefs around that material…”

That is the same decision I made about my own book, although, since ‘climategate’, I am wondering whether to say something more. It’s very difficult to have a conversation that doesn’t generate more heat than light – on which subject, an interesting guest post at Byron’s place today.

On agw as a big red herring

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Byron asked: “Sam, do you agree that there is a significant body of hard-core deniers who are not open to evidence? I am not saying that every contrarian belongs to this group (nor that pathological behaviour is confined to contrarians), simply that there are powerful economic, ideological and social forces leading many to a place of epistemic closure on this matter. Would you agree?”

My simple answer is ‘yes’. Anthropogenic Global Warming (agw) as presented is a major challenge to the status quo, and so all those with interests in preserving the status quo will have a bias to resist the conclusions of agw. These can take many stripes; often, I would accept, there is a reactionary element involved, and there may even be some legacy influence from fossil-fuel providers funding propaganda.

However, it is also true – so it seems to me – that there are hard-core ‘affirmers’ who are equivalently immune to evidence, and that there are “powerful economic, ideological and social forces leading many to a place of epistemic closure” in favour of the agw hypothesis.

To my mind, agw is a plausible hypothesis with a significant amount of supporting evidence. It is less than certain; most of all, the dire predictions are much less than certain, and I tend to see bad theology in them.

Beyond this, I tend to see Liebig’s law as relevant. The dire predictions associated with the IPCC tend to assume, more or less business as usual, ongoing into through the twenty first century. This seems mindless to me. There is not a hope of business being anything like usual for the next fifteen years, let alone the next fifty or hundred. That is seen most explicitly for me in the assumptions employed re: fossil fuel use, but it applies to all the other limits to growth that we are hitting (and Byron has a useful list here). If we take Liebig’s law to apply to the world system as a whole (which I think is reasonable) then it seems highly likely to me that a very great number of the measures and results being sought by agw advocates will be imposed upon human society by reality. Our carbon dioxide emissions, and the whole impact of industrialisation upon the ecosphere, will substantially reduce from present levels. I see this as beyond any choice, whether that choice be made by individuals, nations or humanity as a whole. We in the industrial world are going to have to get used to using a great deal less energy, and soon (my wild-assed guess: 50% less energy in 15 years).

Which is why I see agw as a red herring. Although it makes for some dramatic pictures, the science behind agw is less certain than the science behind other ecological concerns (Peak Oil, deforestation, water scarcity etc), and the prognoses from agw are even less certain. Worse than this, they are alarmist and appeal to fear, and that has theological problems too. I simply do not see what is either achieved or achievable by the IPCC and its cohorts. Whereas something like Transition Towns (on the practical side) and the Dark Mountain project (on the human culture side) – these I find exciting, practical and inspiring.

Two statements agreed by the IPCC

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“Here are two statements that are completely agreed on by the IPCC. It is crucial to be aware of these facts and of their implications.
1. A doubling of CO2, by itself, contributes only about 1C to greenhouse warming. All models project more warming, because, within models, there are positive feedbacks from water vapor and clouds, and these feedbacks are considered by the IPCC to be uncertain.
2. If one assumes all warming over the past century is due to anthropogenic greenhouse forcing, then the derived sensitivity of the climate to a doubling of CO2is less than 1C. The higher sensitivity of existing models is made consistent with observed warming by invoking unknown additional negative forcings from aerosols and solar variability as arbitrary adjustments.
Given the above, the notion that alarming warming is ‘settled science’ should be offensive to any sentient individual, though to be sure, the above is hardly emphasized by the IPCC.”
(Richard Lindzen, from here. H/T WattsUp)

The Hockey Stick Illusion (A.W. Montford)

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The subtitle for this excellent book is ‘Climategate and the corruption of science’ which sums up the sad tale. Montford succeeds in making a technical statistical argument quite readable, which is surely a sign of divine assistance.

In brief, and cutting out much fascinating detail, the story is this:
– until the mid-1990’s the consensus on climate history was that there was a ‘Medieval Warm Period’ (with temperatures higher than today), followed by a ‘Little Ice Age’, and then, from about 1850, a rise in temperature through to today;
– in the late 1990’s a group led by Michael Mann devised a new history in which those highs and lows were flattened out, and the rise in temperature in the twentieth century was emphasised – this is the ‘hockey stick’;
– the scientific rationale for the hockey stick was progressively investigated, especially by Steven McIntyre, and has been comprehensively demolished;
– the scientific credibility of the IPCC in this regard is less than zero;
– the ‘hockey team’ – ie those around Mann and supporting his work – resorted to a great many dirty tricks and obfuscations to confuse this truth. “Climategate” was simply the airing of the dirty laundry (almost certainly a leak from somebody inside who was disgusted by the attempt at covering up the truth).

The funny thing is that the hockey stick as such is pretty marginal to the question of whether AGW is true or not. It can, however, serve as something of a litmus test – anyone who accepts it reveals that they are ill-informed. For me, this is the most significant chart re AGW:

Even if we do nothing (and we won’t, so this is worst case) the CO2 concentration is likely to peak at around 450ppm, roughly equal to a .7C rise in temperature.

The Hockey Stick Illusion (A.W. Montford)

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The subtitle for this excellent book is ‘Climategate and the corruption of science’ which sums up the sad tale. Montford succeeds in making a technical statistical argument quite readable, which is surely a sign of divine assistance.

In brief, and cutting out much fascinating detail, the story is this:
– until the mid-1990’s the consensus on climate history was that there was a ‘Medieval Warm Period’ (with temperatures higher than today), followed by a ‘Little Ice Age’, and then, from about 1850, a rise in temperature through to today;
– in the late 1990’s a group led by Michael Mann devised a new history in which those highs and lows were flattened out, and the rise in temperature in the twentieth century was emphasised – this is the ‘hockey stick’;
– the scientific rationale for the hockey stick was progressively investigated, especially by Steven McIntyre, and has been comprehensively demolished;
– the scientific credibility of the IPCC in this regard is less than zero;
– the ‘hockey team’ – ie those around Mann and supporting his work – resorted to a great many dirty tricks and obfuscations to confuse this truth. “Climategate” was simply the airing of the dirty laundry (almost certainly a leak from somebody inside who was disgusted by the attempt at covering up the truth).

The funny thing is that the hockey stick as such is pretty marginal to the question of whether AGW is true or not. It can, however, serve as something of a litmus test – anyone who accepts it reveals that they are ill-informed. For me, this is the most significant chart re AGW:

Even if we do nothing (and we won’t, so this is worst case) the CO2 concentration is likely to peak at around 450ppm, roughly equal to a .7C rise in temperature.

On being a proper scientist

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I wasn’t going to comment, but I think this is interesting irrespective of AGW:
“The CRU e-mails as published on the internet provide prima facie evidence of determined and co-ordinated refusals to comply with honourable scientific traditions … The principle that scientists should be willing to expose their ideas and results to independent testing and replication by others, which requires the open exchange of data, procedures and materials, is vital.”

My thoughts on the substantive issue are fairly reflected in this post.

Copenhagen was (mostly) irrelevant

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I know I said I wasn’t going to post anything further about AGW – and, really, this isn’t – at least not in the same way. For the purposes of this post I’m going to assume that the mainstream consensus (ie disregarding the extremist forecasts) is basically true, and, in particular, that the models have some connection to reality.


Click ‘full post’ for text.

The first point is to do with the amount of fossil fuel resources available, and the way in which the IPCC overestimates how much there is. I’ve linked to these articles before, but as I suspect the links are often not followed I’m going to set out some of the key claims. (The graph above is taken from this post which is one of the key ones).

The point is a simple one: the IPCC, in their reference scenarios, use estimates of the availability of fossil fuel derived from the IEA which are seriously implausible. The most recent article spelling out why is here. I quote: “Our conclusion is that the assumptions of coal use that the IPCC recommended that climate researchers refer to in calculating their future horror scenarios are completely unrealistic. The question is why at all these gigantic volumes of carbon dioxide emission are to be found among the possible scenarios. The IPCC bears a great responsibility for the fact that thousands of climate researchers around the world have dedicated years of research to calculating temperature increases for scenarios that are completely unrealistic. The consequence is that very large research resources have been wasted to little benefit for us all.” Aleklett points out that the burning of even as much coal as there is is unlikely, due to the political context (Montana in the US) and the lack of local need (Siberia).

The second point is the one underlying the graph above: if human society continues to burn all the fossil fuels that are available, ie including Montana and Siberia, until they are economically exhausted (ie the net return on energy is close to 1:1) then carbon dioxide in the atmosphere will peak at around 480ppm in the second half of the twenty-first century. According to the MAGICC model used at the Oil Drum, this translates into around 1.7ºC above 1990 levels.

The third point that I would make is that ceteris paribus makes morons of us all. The human economic system is dynamic, and, especially in the more free-market oriented societies, there is room to respond to changed circumstances. What I take this to mean is that a) peak oil and associated limits will cause havoc to our economies well in advance of our accessing all the coal, b) the truth of the Limits to Growth perspective will by then be unavoidable for all except the most wilfully obtuse, c) we will as a human community either shift towards sustainable habits of life or we will slaughter ourselves fighting for what is left – in either case the coal will not be accessed.

Which makes me think that the rather extravagant boondoggle proposed in Copenhagen was somewhat besides the point. Moreover, I can’t help but feel that the doom and gloom being put about is counterproductive. It is as if the Victorian clerical cliche of ‘You’re going to burn in hell’ has been resurrected in a green dress; it turned people away then and it is turning people away now. The truth is that we are not in control of the system (any complex system) and we need to leave room for God to be God, and to avoid continuing the intellectual, scientistic and technocratic hubris that drove us into this mess in the first place.

What we need to do is to prepare for the great dislocation. Over the next ten to fifteen years we are going to be jettisoned from the sinking luxury liner and we need to get ready for a much simpler existence in the lifeboat. We need to ask ourselves what is worth saving from our present cornucopia, and work to save what we can. Doing that properly requires rather more prayer and listening to God than is presently in display. I am more and more persuaded that it also requires the adoption of a Ninevite attitude if the lifeboats in their turn are not to sink.

I’ll write something more about the nature of these choices in due course.