Thursday
Mar182010
by 
Bishop Hill
Bishop Hill Economist on global warming
Mar 18, 2010 Climate: CRU Media The Economist adds its considerable voice to the throng of those calling on the public to "move along" because there's nothing to see here. It seems that action is required on global warming not because we are certain of the science but because we are not.
Huh?
There's an editorial here and a briefing here, the latter covering the Hockey Stick story and making all the usual claims about the NAS panel.
Reader Comments (72)
michael,
I will. And unlike you when you say there is no evidence for positive feedbacks, I'll be right in saying that.
'Revenue neutral tax' Frank? now that is a rare beast indeed. I think I'd be more likely to come across a herd of hippogryphs before I come across such a thing.
From an economic point of view, whatever your view of the science, adaptation is the sensible, and most economically sound approach, and the fewer governments and tax barons involved the better.
Morning Frank
it is indeed true that a consensus among scientific experts is prima facie evidence that a given hypothesis is correct
False. Counter examples throughout history of science:
Consensus the earth is flat.
Consensus the earth is at the centre of the universe.
Consensus that washing hands after dissecting cadavers is irrelevant to mother and infant mortality during birth.
Consensus that stomach ulcers cannot be caused by bacteria.
Consensus that science is settled and there's nothing new to learn.
In each case sited, the consensus has proven wrong. Consensus is the method of politics, and not the method of advancement in science, nor of any truth seeking enterprise.
Your premise is proven false by counter example.
Frank again
it's worked before for SO2 so why not CO2? If CO2 is the problem then what is your solution?
Many of us do not believe CO2 is a problem. There is no compelling evidence for it being a problem. There is strong evidence for it being a great thing for our planet: without it there would no life and hence we could not be having this discussion about it.
And SO2 is a very cheap way to keep the planet from over heating, if that proved to be a problem in the future. Spray it into the atmosphere at altitude, as happens naturally in the eruption of volcanoes, and hey presto, cooling. The eruption of Mt Pinatubo is the example.
SO2 induced global cooling would likely cost a fraction of the money being spent already on media campaigns and AGW propaganda. It's a real, practical and cost effective way of tackling a warming problem, if and when that occurs. So, naturally, it will be rejected by all AGW proponents as despicable.
Irony meter on: Perhaps the "unprecedented warming" is a result of the meddling of SO2 emissions in the first place.
I wonder, Frank, just what you have against a warmer planet in any case? What is so bad about that?
Drew,
I said prima facie evidence - in other words, "the race is not always to the strong, nor the battle to the swift - but that's the way to bet". I didn't claim it was proof - evidence generally isn't proof - and I didn't even say it was all of the evidence or even the most important. It is a simple rebuttal to the claim that there is no evidence.
The argument 'scientists are sometimes wrong' if it was valid could be used to deny any scientific statement whatsoever. It is not enough to say that, you need to provide a reason why so many people may have got it wrong, an actual rebuttal or falsification of their arguments. That is how it worked in all of the cases you mention.
As I said, either you believe the scientific method is the most reliable way to discover the truth or you don't.
"And unlike you when you say there is no evidence for positive feedbacks, I'll be right in saying that."
The thing that so upsets those of us who are in the poltical foresight and planning movement is the way that the deniers oppose the science of planning and foresight. This is nothing short of a well funded campaign against science itself! The anti science movement is well established, and will not retreat from its stance. The science is settled, Tonga is a menace.
It is up to us to make the case aggressively and forcefully. We must not err on the side of underestimating the dangers that Tonga poses to human civilization and life on this planet of ours, so tiny and blue, so fragile, when seen from outer space. I am a parent and I think of the children, and I am a hygienist also, and cannot bear the body odor of these filthy fundamentalist deniers.
So joint the fight for science, and attack the deniers, and lets get Tonga nuked now!
Frank O'Dwyer makes the important point: It's about the credibility of the threat. Ridiculing the precautionary principle by pointing to hypothetical beliefs is besides the point.
If the central estimate of climate sensitivty is 3 deg (2 - 4.5) per doubling of CO2 then a higher uncertainty in that estimate (say, between 1 and 6) increases the risk rather than decreases it. The risk is only decreased if the threat is convincingly shown to be much less: You must be very certain that it's not larger than, say, 1 deg per doubling. Are you that sure? Or do you just feel lucky?
Hi Bart,
When you first hear about a new hazard, the only rational action is to find out more about the hazard. Jumping straight into doing something is not rational.
When you hear for the umpteenth time about the hazard and it never appears then the rational action is to ignore the 'hazard' and deal with whatever happens, if and when it happens.
I like Ronald Reagan's phrase:
"You must be very certain that it's not larger than, say, 1 deg per doubling. Are you that sure? Or do you just feel lucky?"
I am sure. I think we should be worrying about climate fluctuations, warming and cooling, but that cooling is the greater threat, and that the causes of both are unknown. And that geoengineering is far more dangerous than leaving well alone.
It is true, I am ridiculing the precautionary principle, and that is because it is ridiculous. It is a variant of Pascal's Wager, and is invoked for the same reason and with the same illegitimacy.
Pascal was faced with a problem. The problem was that the proofs he could find of the truth of the Christian religion were not of the standard usual to make us accept a scientific hypothesis. He therefore needed some reason for belief that would not depend on the quality of the proofs.
He thus invoked the argument from probability. The return is the cost times the probability of that cost. In the case of eternal damnation, the cost is huge, the probability low, the return from belief therefore positive and maybe high.
The problem with the argument is it does not specify what kind of belief, and it begs the question whether there is any probability at all of damnation. It can be used, as I used it earlier, to justify almost anything, including justifying two incompatible courses. For example, to believe in Islam and to believe in Christianity.
Now, when confronted with this logical absurdity, the proponents of the argument say that their situaiton is different. The reason is that warming is a real threat. Yes, but now they are trapped. The reason they offered the precautionary principle was the same as the reason Pascal offered his wager: the purpose was to avoid having to argue about how convincing the evidence was. The argument was of the form, it doesn't have to be convincin, it only has to be remotely probable.
When we show that logically it does indeed have to be more than remotely probable, it has to be at least more probable than inconsistent alternatives, they go back to asserting that their hypothesis is likely. This is what was at issue all along, and what the invocation of the PP was trying to avoid arguing about.
Fact is, the PP is a sort of petitio prinicipe. There is no way out of establishing that action on reducing CO2 is a sensible course of action, by the same standards we apply to all courses of action. You can't get out of it by citing the PP. Get real, there is no evidence that reducing CO2 will reduce temperatures, and even less that cap-and-trade or windmills or any of these other idiotic proposals will reduce CO2. Its a farce, and invocation of the PP is evidence for that.
If the evidence were real and convincing, we would never have to invoke the PP to avoid arguing about it.
michel,
Yes, Pascal's wager is a fallacy. However I will assume that you agree that not every precautionary measure is an example of Pascal's wager. What in your view is the difference between a valid precaution and Pascal's wager?
Its an interesting question, if rather academic. One key characteristic is that PW arguments seem to propose action to minimize a risk while specifying only the cost of the risk and not its probability. A second is that PW arguments are invokable for actions which are inconsistent with the one they are cited to support.
The consequence of these characteristics is that they tend to support taking actions which have poor risk reward ratios, and which have high and unquantified opportunity costs, and which do not minimize the total risks of what one seeks to avoid, though they may diminish the risks of one particular way of incurring them.
These two characteristics apply to both climate and to religious PW arguments. Suppose Pascal's wager were accepted in favor of one particular religion. This has real costs. Also, we do avoid one particular route to eternal damnation, but alas, there are others, and we cannot avoid them all since to adopt the wrong religion means that if one got it wrong, one is damned for not having adopted another. The same applies to CO2. It is true that lowering CO2 ppm will lower or eliminate the risk of human extinction due to rising CO2. But it will not lower the risk of human exinction due to nuclear war, epidemic, cometary impact,,,and so on. We cannot accept all religions for logical reasons. We cannot take precautions against all possible threats for reasons of resource.
Perhaps a better question is, how do we show that PW arguments are fallacious? The answer is familiar from a context in which proposals for action are brought up and debated every day, and in which careers and money are at stake. That is business planning.
In business planning, groups commonly advocate proposals. The background is always limited resources. They always have reasons. It is quite common to raise an assessment question in the following form:
If we are doing X in order to achieve Y, then Y must be the best way, or at least a good way, of doing X. Is it?
The method is effective when applied to political proposals too, but is never used in Government. It may be contrary to Civil Service employment contracts. It is effective in medicine.
Take a medical example. We wish to reduce the incidence of heart attacks. Someone proposes prescribing statins to the entire population over 40. We use a statistic, the number needed to treat, to assess the effectiveness of different proposals to do this. With statins, this number is in the hundreds. We also look at the side effects. By doing this, we can compare different measures to achieve the goal. Of course, we still have to debate whether the general reduction of heart attacks is relatively more or less important than the reduction of osteoporosis by prescription of the recent epensive generation of drugs. Because at some point we will come up against resource constraints, and be unable to do it all.
Take another practical example. In ocean voyaging in small boats, a gybe preventer is sometimes rigged. It is clear that unplanned gybes can be catastrophic. It is also clear that preventers do stop them. We never hear the argument 'if there is the smallest chance....' in favour of rigging them. The debate goes along quite different lines. It is that there is a risk, how large is hard to say, but that there are real costs of rigging preventers, and they have to do with how easy and quick and safe it is to release them in circumstances when you have to. Others agree about gybes using conventional boomed rigs, but think other measures than preventers should be employed.
Where does it leave us on PW, the alleged 'precautionary principle' and climate? There is no such thing as the 'precautionary principle' in the sense that it is used, a well known and legitimate form of argument for policy. There is only a proposal for action: the lowering of CO2, and at the moment, a proposal for a means to that end, the use of cap-and-trade. Precautionary measures are no different than other measures, it is a way of describing measures, not a way of justifying them, to call them precautionary. It is a bit like 'strategy'. To say that we wish to make an investment for strategic reasons invites the question, yes, and what are those strategic reasons? To say that we are lowering CO2 for precautionary reasons invites the question, yes, and what are those reasons?
In the end you cannot avoid discussing why it is important to lower CO2, and why the measures you propose will do it. You have to start by arguing in detail the case that doubling CO2 will warm the planet with catastrophic effects. At some level, this is possible, just as it is possible that at this moment there is a comet with our name on it heading earthwards. The question is, how likely, and how much of a priority this represents.
We can say one thing about this socially. Where the arguments in favor of action are strong and clear, PW is never cited. We do not say to patients with blocked arteries, you should diet, exercise and take statins because no matter how small the chance of death in the next six months..... We say to them that the statistics show that untreated you have this chance, treated this, the side effects are this, so do it. We prescribe warfarin to atrial fibrillation patients not on the basis that no matter how small the chance.... We say, off warfarin your chance of clotting stroke is several times the average. On warfarin it falls to about average. And the chance of a bleeding stroke will rise, but from very low levels and will stay at very low levels. This is, you can see from the numbers, a sensible regime.
There are cases where we can either prescribe warfarin, or take some other life saving measure, but not both. And there we have a difficult problem. You do not find us using arguments of the form 'no matter how low the risk....' there either. That is probably the closes analogue to the climate case.
We do not have the analysis done on climate. We have not shown that the costs of planetary warming are of an order to claim priority of treatment. We don't have the evidence that lowering ppm is going to lower temperature. We have still less evidence that cap-and-trade is actually going to lower ppm. But we call anyone who resists the last a 'denialist'.
The nearest analogue I can come to is if those in favour of prescribing statins + cholesterol reducers to the entire population over 40 were to call those who want costs and benefits laid out clearly before doing it 'denialists' and 'delayers'. Well no, we were not, and the recent evidence that adding cholesterol reducers to statin prescriptions raises, and does not lower, death rates, confirms that we were right to want more research and better understanding of the underlying mechanism.
First, do no harm.
Michel,
Thank you for everything you've written here, especially the above, the very clear demolition of the precautionary principle and the very helpful lessons from policy choices in medicine. I've long hoped for those with experience in the latter to come and help those of us struggling with the AGW hydra.
Just a word on our friend Pascal. Everyone has bad days and for me the famous Wager was one of his. I continue to love the fellow for the combination of brilliance in maths and passion that cried out "Fire" as he experienced the Holy Spirit. It would have been much better not to have tried to combine these two areas of interest in the wager though - and the way you've shed light on AGW's use of PP through PW is a great help. Thank you.
Do no harm indeed Michel.
An hippocratic oath for politicians and the exponentially growing population of unelected global policy makers is highly desirable.
Gentlemen, I sense this thread is ageing and will soon subside, but I'd like to thank Bart, and Frank, and Michel and the other participants for what has been a useful, and on the whole productive and polite debate. It's engaged thought processes, and those (even if they do emit CO2) are very valuable. Thank you.
"It is true that lowering CO2 ppm will lower or eliminate the risk of human extinction due to rising CO2."
Don't forget that we are closer to the lower bound of CO2 tolerance (around 250ppm) than we are to the upper (7000ppm)
Frank O'Dwyer,
Cap-and-trade is the next best thing - it's worked before for SO2 so why not CO2? If CO2 is the problem then what is your solution?
I'm a chemical engineer who's designed processes to contain SO2 emissions. The difference in relation to CO2 emissions in terms of the necessary technological and economic effort is of orders of magnitude - you might as well ask, "I can crush an ant between my fingers, why should that not work with an elephant?". To remove SO2 from the emissions in power plants, incinerators, industrial facilities etc requires only that the emissions flow through a water scrubber - in very simple terms, essentially a tower with lots of water sprays against which the gaseous emissions flow. The SO2 is ultimately captured as calcium sulphate which does have some uses.
The installation of such scrubbers requires some capital investment but it's essentially a very well-known and even simple technology, and the point is, you can just add them to any already existing industrial process.
CO2 can't be easily captured with a scrubber - and whenever suggestions are made to that efffect, lots of people immediately say that it's unreliable because the CO2 could escape etc (something nobody ever said about SO2). On top of that, the amounts of CO2 raw emissions are many orders of magnitude higher than those of SO2.
So while SO2 reduction just requires a relatively minor investment to add an already available technology to existing facilities, CO2 reduction requires the total revamping of the energy and transport sectors, with technologies that don't really exist.
There is no possible comparison between the two in terms of technical and economic feasibilities. Any chemical engineer will tell you that. To say "we could reduce SO2, why not CO2" is just to confuse the issue and at the very least reveals a huge ignorance as to the technologies and invesments involved.
Frank referred to a 2002 Science article on water vapor feedback by Soden et al. The method used was to track reactions to the Pinaubo eruption. The conclusion, but I am not very sure of the robustness of the chain of argument, was that observation confirmed an amplifying effect. With however some quite important caveats:
[blockquote]This study highlights the role of water vapor
feedback in amplifying the global cooling after
the eruption of Mount Pinatubo. We note, how-
ever, that Mount Pinatubo does not provide a
perfect proxy for global warming, because the
nature of the external radiative forcing obvious-
ly differs between the two. Nevertheless, the
results described here provide key evidence of
the reliability of water vapor feedback predicted
by current climate models in response to a
global perturbation in the radiative energy bal-
ance. Given the importance of water vapor
feedback in determining climate sensitivity,
such confirmation is essential to the use of these
models for global warming projections.[/blockquote]
Interesting. One would want something more definitive than this before moving to spend trillions, but its interesting.
The writers at the Economist disappeared up their fundamental orifices a long time ago. After subscribing for over a decade, I finally gave up on them last year.
Michel, it's angled brackets with blockquote to get
Tags a for a link, like this one to Climate Audit, b for bold and i for italic work just as they do in HTML, within a paragraph or blockquote. If in doubt, the Preview Post button gives a reasonable idea of what the post will look like. The main 'bug' in the rendering being the gap between paragraphs one and two after a blockquote.
That gap would not have been shown correctly in other words unless I had inserted three CRs.
But that one only needed two CRs. And I just discovered that the code tag for
monospace fontworks as well, though it's needed on every line of a block of source code, such as:int main() {printf("Hello World!\n");return 0;}But that loses the indentation in the original. And other more complex tags don't work at all, like this YouTube video:
<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/9Xa7s2af_1Q&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param></object>
(And people have the nerve to call me a nerd. Ah well.)
Many thanks for that lesson in posting elegance Richard. I'd been wondering about the blockquote option listed below for sometime, but didn't want to try my luck.