Friday, February 23, 2007


David Friedman writes:

I've recently been involved in an exchange with Mike Huben in the comments section of an earlier post to this blog, having to do with global warming, hurricanes, and Chris Landsea's pulling out of the IPCC-the group that does the "official" reports on world climate-a few years ago. Interested people may want to look at our exchange and at the web pages cited.

There is a more general issue that such disputes raise: How, in controversies where most of us do not know enough to form independent opinions, one should decide who to believe. One way is to look at the incentives various people have to express the views they do. Let me start with the case of nanotech-specifically, whether it presents dangers that call for government regulation. I've been involved, at least peripherally, for a long time and know some of the people at the Foresight Institute, the group that pushed the idea of nanotech for many years before it became suddenly fashionable.

One thing I know about them is that that their general political biases are libertarian. Hence when I observe them expressing serious concerns about the dangers of unregulated nanotech, I am inclined to take it seriously. They may be wrong, but they aren't believing it because they want to believe it.

Mike Huben, if I understand him correctly, wants to view criticism of evidence for global warming as the work of sinister interest groups, in particular energy companies. I suspect that to some degree he is right; clearly that are industries that will be injured if countries adopt the sorts of policies recommended by those concerned with the threat of global warming, and I expect such industries do their best to push arguments that it is in their interest to push.

On the other hand, a scientist such as Landsea, who apparently wrote a good deal of the relevant part of the previous IPCC report, has no such incentive-unless Mike can point to evidence that he is being secretly funded by the oil companies, which nobody seems to be claiming. It's hard to see any likely reason for his actions other than the belief that the scientific work of himself and others was being misrepresented in order to push a political agenda.

And the followup articles-the ones Mike found and pointed out to the rest of us-suggest that in fact Landsea's view of the subject was correct and that his protest was one factor in pushing the IPCC, in its most recent report, to give a mostly accurate account of the current consensus. Their summary account reported that there was no clear evidence of a trend to more hurricanes. One of the authors of the relevant part of the report, decrying misrepresentations in the media, wrote that: "We concluded that the question of whether there was a greenhouse-cyclone link was pretty much a toss of a coin at the present state of the science, with just a slight leaning towards the likelihood of such a link."

My current conclusion, looking over what I can see of the opinions of people who don't have an obvious axe to grind in either direction, is that global warming is probably real, is probably but not certainly anthropogenic, is probably not going to have large effects on size and frequency of hurricanes and is probably not going to have large effects on sea level. It is a real problem but not, on current evidence, an impending catastrophe.

Mike, and many other people, see it as a much bigger problem than I do. My reason for distrusting their conclusions is the same as Mike's reason for distrusting the conclusions of global warming sceptics: On the whole and with, I am sure, some exceptions, they appear to me to be believing what they want to believe. I see it that way because:

1. Governments, and people in government, seek power for obvious reasons. Over the past fifty years the intellectual justification for the large expansion in government power from about 1930-1970 has largely collapsed. The belief that capitalism is inherently unstable and inefficient and must be fixed with large elements of governmental intervention and central planning is no longer taken very seriously by either the general public or economists. Environmentalism in general and global warming in particular provide new arguments for expanded government power, new taxes, and the like.

That does not mean, of course, that those arguments are wrong, but it does mean that there are a lot of people who have an incentive to support them whether wrong or right. That seems to me consistent with what I observe-what is probably a real problem being extensively exaggerated for political reasons, with a predicted sea level rise of up to 80 cm over 93 years being reported in terms of massive flooding around the world, converting the World Trade Center Site into an aquarium in the piece I commented on in my earlier post.

2. Global warming provides arguments for things that a lot of people, mostly left of center, want to do anyway-shift lifestyles away from automobiles towards mass transit, reduce consumption of depletable resources, and the like. Environmentalism is in part a real argument, in part a religion, in part an aesthetic; the second and third parts make people too willing to accept the first.

Which gets me to Mike's various queries about why I choose to align myself with the forces of evil and ignorance by expressing skepticism about the horrors likely to arise from global warming. Simply put, I am skeptical of conclusions that appear to go well beyond the scientific evidence, pushed by people who have reasons to want other people to believe them.



When coastal engineers decide whether to dredge sand and pump it onto an eroded beach, they use mathematical models to predict how much sand they will need, when and where they must apply it, the rate it will move and how long the project will survive in the face of coastal storms and erosion. Orrin H. Pilkey, a coastal geologist and emeritus professor at Duke, recommends another approach: just dredge up a lot of sand and dump it on the beach willy-nilly. This "kamikaze engineering" might not last very long, he says, but projects built according to models do not usually last very long either, and at least his approach would not lull anyone into false mathematical certitude.

Now Dr. Pilkey and his daughter Linda Pilkey-Jarvis, a geologist in the Washington State Department of Geology, have expanded this view into an overall attack on the use of computer programs to model nature. Nature is too complex, they say, and depends on too many processes that are poorly understood or little monitored - whether the process is the feedback effects of cloud cover on global warming or the movement of grains of sand on a beach.

Their book, "Useless Arithmetic: Why Environmental Scientists Can't Predict the Future," originated in a seminar Dr. Pilkey organized at Duke to look into the performance of mathematical models used in coastal geology. Among other things, participants concluded that beach modelers applied too many fixed values to phenomena that actually change quite a lot. For example, "assumed average wave height," a variable crucial for many models, assumes that all waves hit the beach in the same way, that they are all the same height and that their patterns will not change over time. But, the authors say, that's not the way things work.

Also, modelers' formulas may include coefficients (the authors call them "fudge factors") to ensure that they come out right. And the modelers may not check to see whether projects performed as predicted. Eventually, the seminar participants widened the project, concluding that erroneous assumptions, fudge factors and the reluctance to check predictions against unruly natural outcomes produce models with, as the authors put it, "no demonstrable basis in nature."

Among other problems, they cite much-modeled but nevertheless collapsed North Atlantic fishing stocks, poisonous pools unexpectedly produced by open pit mining, and invasive plants and animals that routinely outflank their modelers. Two issues, the authors say, illustrate other problems with modeling.

One is climate change, in which, they say, experts' justifiable caution about model uncertainties can encourage them to ignore accumulating evidence from the real world. The other is the movement of nuclear waste through an underground storage site at Yucca Mountain in Nevada, not because it has failed - it has yet to be built - but because they say it is unreasonable to expect accurate predictions of what will happen far into the future - in this extreme case, tens or even hundreds of thousands of years from now.

Along the way, Dr. Pilkey and Ms. Pilkey-Jarvis describe and explain a host of modeling terms, including quantitative and qualitative models (models that seek to answer precise questions with more or less precise numbers, as against models that seek to discern environmental trends). They also discuss concepts like model sensitivity - the analysis of parameters included in a model to see which ones, if changed, are most likely to change model results.

But, the authors say it is important to remember that model sensitivity assesses the parameter's importance in the model, not necessarily in nature. If a model itself is "a poor representation of reality," they write, "determining the sensitivity of an individual parameter in the model is a meaningless pursuit."

Given the problems with models, should we abandon them altogether? Perhaps, the authors say. Their favored alternative seems to be adaptive management, in which policymakers may start with a model of how a given ecosystem works, but make constant observations in the field, altering their policies as conditions change. But that approach has drawbacks, among them requirements for assiduous monitoring, flexible planning and a willingness to change courses in midstream. For practical and political reasons, all are hard to achieve. Besides, they acknowledge, people seem to have such a powerful desire to defend policies with formulas (or "fig leaves," as the authors call them), that managers keep applying them, long after their utility has been called into question.

So the authors offer some suggestions for using models better. We could, for example, pay more attention to nature, monitoring our streams, beaches, forests or fields to accumulate information on how living things and their environments interact. That kind of data is crucial for models. Modeling should be transparent. That is, any interested person should be able to see and understand how the model works - what factors it weighs heaviest, what coefficients it includes, what phenomena it leaves out, and so on.

Also, modelers should say explicitly what assumptions they make. And instead of demanding to know exactly how high seas will rise or how many fish will be left in them or what the average global temperature will be in 20 years, they argue, we should seek to discern simply whether seas are rising, fish stocks are falling and average temperatures are increasing.

And we should couple these models with observations from the field. Models should be regarded as producing "ballpark figures," they write, not accurate impact forecasts. "If we wish to stay within the bounds of reality we must look to a more qualitative future," the authors write, "a future where there will be no certain answers to many of the important questions we have about the future of human interactions with the earth."

Source. More information about the new book can be found here.


Some pretty unsettling science. Is this why there is some warming at our North pole but none at our South pole? The fact that the same pattern is seen on Mars makes it thought-provoking

One pole of the sun is cooler than the other. That's the surprising conclusion announced today by scientists who have been analyzing data from the ESA-NASA Ulysses spacecraft. Ulysses is the only ship in the NASA or European fleet capable of flying over the sun's poles, a result of the spacecraft's uniquely-tilted orbit. Its ability to study the sun's unexplored polar regions is prized by solar physicists. Ulysses' first polar flybys in 1994 and 1995 revealed the asymmetry-"a 7 to 8 percent difference in temperature," says Ulysses science team member George Gloeckler of the University of Maryland. The measurement was both mysterious and a little hard to believe. What would make the sun lopsided in this way? There's still no definitive answer to that question, but now at least researchers know the effect is real. Ulysses has returned to the sun's South Pole in 2007 and "recent observations show that the average temperature ... is virtually identical to what we saw 12 years ago," says Gloeckler.

Taking the sun's temperature is tricky business. The spacecraft can't descend to the surface and insert a thermometer. Instead, Ulysses samples the solar wind at a safe remove of 300 million km. "We measure the abundance of two oxygen ions found in the solar wind. The ratio O6+/O7+ tells us the temperature of the gas," explains Gloeckler. He is the principal investigator of the instrument onboard Ulysses that does this, the Solar Wind Ion Composition Spectrometer or "SWICS." According to SWICS, the average temperature of the sun's polar wind is about one million degrees C. But over one pole the wind is about 80,000 degrees cooler than over the other pole. Researchers believe the solar wind at Ulysses is telling them something about polar conditions close to the surface of the sun. "The solar wind comes from the poles," explains Arik Posner, Ulysses Program Scientist at NASA headquarters. "The sun's magnetic field opens up over the poles and allows some of the sun's atmosphere to escape." These openings are called "coronal holes," and the hot atmosphere that rushes out is the solar wind.

Back to the original question: What does the temperature difference mean? "Perhaps the structure of the sun's atmosphere over the two poles is different," he speculates. We have an analogy here on Earth. The stratosphere over the South Pole is colder, on average, than the stratosphere over the North Pole. The reason has to do with the uneven distribution of land on Earth (most land is in the north) plus complex atmospheric circulation patterns.

In the case of the sun, the difference is not land but magnetism. Apparently, something about the sun's north magnetic pole keeps the solar atmosphere above it a trifle cooler. Proof: The "cool spot" follows the north magnetic pole when the sun's poles flip. "The sun's magnetic poles have reversed polarity since the 1994 flyby-an effect of the 11-year sunspot cycle," notes Posner. Lo and behold, "the temperature asymmetry has also reversed. So it appears to be a magnetic phenomenon."



By His Eminence, Dr. George Pell, Cardinal Archbishop of Sydney

Global warming doomsdayers were out and about in a big way recently, but the rain came in Central Queensland and then here in Sydney. January also was unusually cool. We have been subjected to a lot of nonsense about climate disasters as some zealots have been painting extreme scenarios to frighten us. They claim ocean levels are about to rise spectacularly, that there could be the occasional tsunami as high as an eight story building, the Amazon basin could be destroyed as the ice cap in the Arctic and in Greenland melts. An overseas magazine called for Nuremberg-style trials for global warming skeptics while a U.S.A. television correspondent compared skeptics to "holocaust deniers".

A local newspaper editorial's complaint about the doomsdayers' religious enthusiasm is unfair to mainstream Christianity. Christians don't go against reason although we sometimes go beyond it in faith to embrace probabilities. What we were seeing from the doomsdayers was an induced dose of mild hysteria, semi-religious if you like, but dangerously close to superstition.

I am deeply skeptical about man-made catastrophic global warming, but still open to further evidence. I would be surprised if industrial pollution, and carbon emissions, had no ill effect at all. But enough is enough. A few fixed points might provide some light.

We know that enormous climate changes have occurred in world history, e.g. the Ice Ages and Noah's flood, where human causation could only be negligible. Neither should it be too surprising to learn that the media during the last 100 years has alternated between promoting fears of a coming Ice Age and fear of global warming! Terrible droughts are not infrequent in Australian history, sometimes lasting seven or eight years, as with the Federation Drought and in the 1930s. One drought lasted fourteen years.

We all know that a cool January does not mean much in the long run, but neither does evidence from a few years only. Scaremongers have used temperature fluctuations in limited periods and places to misrepresent longer patterns. The evidence on warming is mixed, often exaggerated, but often reassuring. Global warming has been increasing constantly since 1975 at the rate of less than one fifth of a degree centigrade per decade.

The concentration of carbon dioxide increased surface temperatures more in winter than in summer and especially in mid and high latitudes over land, while there was a global cooling of the stratosphere. The East Anglia university climate research unit found that global temperatures did not increase between 1998 - 2005 and a recent NASA satellite found that the Southern Hemisphere has not warmed in the past 25 years. Is mild global warming a Northern phenomenon?

While we might have been alarmed by the sighting of an iceberg off Dunedin as large as an aircraft carrier we should be consoled by the news that the Antarctic is getting colder and the ice is growing there. The science is more complicated than the propaganda!



Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is generally to promote themselves as wiser and better than everyone else, truth regardless.

Global warming has taken the place of Communism as an absurdity that "liberals" will defend to the death regardless of the evidence showing its folly. Evidence never has mattered to real Leftists

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