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Sunday, January 08, 2006

Or, the loneliness of the honest skeptic. Philip points to this essay by Hendrik Tennekes, retired Director of Research, Royal Netherlands Meteorological Institute, and offers some tea - Earl Grey, hot - to enjoy while we consider this thoughtful meditation on the problems of being skeptical and the necessity of doing so.

Tennekes seems to be what Cosma Shalizi calls a Left Popperian in that he requires some rigor in predictions and simulations. As Tennekes puts it:

His [Popper] claim that scientists should be held accountable for the accuracy of their predictions boils down to the requirement that they have to compute in advance the reliability of their computations. For complex models, Popper wrote, this demand leads to "infinite regress": computations of forecast skill are much harder than the forecasts themselves, and the next level, forecasting the skill of the skill forecast, is insurmountable when a complex system such as the climate is involved. Popper concluded that the positivist claims of science are in general unwarranted.
This is similar to the assertions of Trout & Bishop.
It is time for epistemology to take its rightful place alongside ethics as a discipline that offers practical, real-world recommendations for living. In our society, the powerful are at least sometimes asked to provide a moral justification for their actions. And there is at least sometimes a heavy price to be paid when a person, particularly an elected official, is caught engaging in immoral actions or defending clearly immoral policies. But our society hands out few sanctions to those who promote and defend policies supported by appallingly weak reasoning. Too often, condemnation is meted out only after the policies have been implemented and have led to horrible results: irresponsible war and spilt blood or the needless ruin of people’s prospects and opportunities. Epistemology is a serious business for at least two reasons. First, epistemology guides reasoning, and we reason about everything. If one embraces a defective morality, one’s ability to act ethically is compromised. But if one embraces a defective epistemology, one’s ability to act effectively in all areas of life is compromised. Second, people don’t fully appreciate the risks and dangers of poor reasoning. Everyone knows the danger of intentional evil; but few fully appreciate the real risks and untold damage wrought by apparently upstanding folk who embrace and act on bad epistemological principles. Such people don’t look dangerous. But they are.
Tennekes applies this kind of thinking to climate models and finds them to be dodgy in the extreme, even when they are bolstered by "Ensemble Forecasting, which in fact is a poor man's version of producing a guess at the probability density function of a deterministic forecast."
. . . ensemble forecasting and multi-model forecasting have become common in climate research, too. But fundamental questions concerning the prediction horizon are being avoided like the plague. There exists no sound theoretical framework for climate predictability studies. As a turbulence specialist, I am aware that such a framework would require the development of a statistical-dynamic theory of the general circulation, a theory that deals with eddy fluxes and the like. But the very thought is anathema to the mainstream of dynamical meteorology.

Climate models are quasi-deterministic and have to simulate daily circulation patterns for tens of years on end before average values can be found. The much more challenging problem of producing a theory of climate forecast skill is left by the wayside. In IPCC-documents one finds phrases like "climate surprises", showing that the IPCC-staff is unaware of the ignorance it reveals by that choice of words, or unwilling to state forcefully that climate predictability research deserves much more attention than it has received so far.

This is no minor matter. . .

I protest against overwhelming pressure to adhere to the climate change dogma promoted by the adherents of IPCC. I was brought up in a fundamentalist protestant environment, and have become very sensitive to everything that smells like an orthodox belief system.

The advantages of accepting a dogma or paradigm are only too clear. One no longer has to query the foundations of one's convictions, one enjoys the many advantages of belonging to a group that enjoys political power, one can participate in the benefits that the group provides, and one can delegate questions of responsibility and accountability to the leadership. In brief, the moment one accepts a dogma, one stops being an independent scientist.

The issues here aren't just the arcane calculations of climate scientists, they are also how those results bear on policy. That's what brings to mind Shalizi's ideas about Popper.
Popper was a democrat, an egalitarian and a humanitarian, but with a decided and very characteristic twist. Usually democracy is justified on some such grounds as "the sovereignty of the people" or the like, but Popper rejected that altogether. The problem of politics is not Who should rule? but How can we correct mistakes of policy without violence?; not How can we make people good or happy? but How can we minimize avoidable suffering?; not What is the best state? but What can we do now to make things better? The virtues of democracy is that, of all known systems, it is the one where policy can be reformed most peacefully and most rationally, and the one which is least likely to inflict or condone needless or unequal suffering. As for the virtues of piece-meal social engineering and reform over the construction of Utopias and revolutions, one would think they'd speak for themselves after the twentieth century; but no. Popper is often, with Hayek, associated with a return to classical liberalism, or rather a certain caricature of it which sees no role for any social institutions but markets and a minimal nightwatchman state to enforce property rights. I think this is a gross misunderstanding, and that his actual, sound, political theory is quite compatible with the best traditions of social democracy; I would be happy to call myself a Left Popperian, if I thought anyone would get it.
Tennekes applies this style to climate modelling issues.
I cannot bring myself to accept any type of prediction paradigm, and choose a adaptation paradigm instead. This brings me in the vicinity of Roger Pielke Sr.'s emphasis on land-use changes and Ronald Brunner's modest bottom-up alternatives. It goes without saying that I abhor such dogmas as various claims to Manage The Planet or Greenpeace's belief in Saving the Earth. These ideologies presuppose that the intelligence of Homo sapiens is capable of such feats. However, I know of no evidence to support such claims.
What makes this more than a fussy debate among specialists, more than an academic noogie war, is that the true believers propose massive socio-economic change in response to the threats they see from those predictions. And if they are wrong, as seems quite possible when we examine the scientific details? Worse, they can't even promise that their draconian alterations of society will avoid the threatened melt down. At best the inevitable may be delayed by a very small amount of time. We would be far wiser to choose a democratic, piece-meal approach that seeks to minimize harm and is sufficiently responsive and agile to usefully react to improved assessments of the situation as events unfold.

posted by back40 | 1/08/2006 12:04:00 PM


Just the other day I was asking myself "I wonder if a person could make a template for blogger that would look like back40's work in MT?". Nice.

By Blogger Philip Small, at 4:41 PM  

Blogger tags are much like MT tags. I started on blogger long ago. Actually I started keeping an open log that supported comments and such using Grey Matter before there was a blogger. They all have the same problems to solve so and have similar solutions.

The defect they both have to my mind is that the posts are not kept in easily changed clear text, but then I'm a command line kind of guy.

By Blogger back40, at 5:19 PM  

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