Saturday, June 24, 2006

Horse Hockey

Speaking of underdetermination (which I was in my last post, in case you were wondering), I've been thinking quite a bit about the recent discussion by a panel convened by the National Academies regarding global warming. The so-called "hockey stick" data purports to show that the warming trend induced by human activity is clearly more significant than has often been admitted (the data are said to form a "hockey stick" curve because when graphed they show a very steady, level trend for a long time that suddenly curves sharply upwards, like the blade on a hockey stick).

The evidence is supposed to be valid for a period of more than 2000 years, even though actual temperature data are available for less then 500 of those years, but I don't think anyone seriously doubts that human activity has some effect on temperature data. Two things are in serious dispute, however. First, what is the nature and extent of that effect and, second, what normative conclusions follow from our awareness of that effect.

One is tempted to leave the first question to the scientists, but it is because of the way scientists famously mess up questions such as the second one that it is even more tempting to monitor their contributions to the first question as well. Scientists have a notoriously bad sense of what follows from what in a normative context, and very often it is what they think follows from what in a normative context that determines what they think follows from what in a purely empirical context. This is unfortunate, but it is not surprising, since this is probably true for most folks in most contexts: we are, after all, political animals.

In the case of this panel's study, some politicians have argued that the data was selected by the scientists themselves in such a way as to produce the effects that they themselves expected. Their response?
"I saw nothing that spoke to me of any manipulation," said one member, Peter Bloomfield, a statistics professor at North Carolina State University. He added that his impression was that the study was "an honest attempt to construct a data analysis procedure."
What did you expect him to say? "Sure, we cooked the books. Everybody does." He wouldn't have said that even if he had believed it. But of course he didn't believe that--he believed that what he did say was true. However, his mere belief doesn't actually make it true, and the selection and analysis of data in a scientific context is precisely one of those areas where scientists themselves are the least competent to make judgments such as the one this guy made. It is not really clear whether an outside observer could make such judgments either: science is one of those areas of human knowledge that fools us into thinking that there is such a thing as objectivity about observational data and the theories that attempt to explain them, but in this particular instance, Nietzsche was actually right about something--he famously wrote, in Beyond Good and Evil, that science is nothing more than one more interpretation, among many possible interpretations, of the world we observe. All interpretations are open to revision, especially those about which we are so sure as to be unable to see possible alternatives.

So it's worth keeping an eye on these reports--in some cases they may actually come close to the truth, but if the history of science teaches us anything at all, it teaches us that science itself is just a long sequence of theories and explanations being proved false. Why should any of these theories about the climate be exceptions to that long and invariable history?

9 comments:

djr said...

I'm not sure what I think about hockey sticks, climate science, and politics -- I'm not so skeptical as you are, but I'm skeptical enough to be embarassed by people like Al Gore. What I really want to make abundantly clear, though, despite everything you've said here, is something that is far more important for the short-term, though no doubt insignificant in the not-so-short-term: your webpage is really broken!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Paul Halsall said...

I demolish you at http://englisheclectic.blogspot.com/2006/07/global-warming.html

Vitae Scrutator said...

Well, it's good to get demolished every now and then, and it's been so long since anyone has really demolished me, well, I just welcome your attempt.

I do have to agree with you to a certain extent--things seem decidedly warmer to me, as well. When I was growing up in the 1960s it was rare to have 90 degree days, let alone weeks or months, here in Ohio; now they happen every summer.

But if your prediction is right--the effects of Celine Dion alone will reverse any warming trends.

You may be interested to know that my department has just hired to new people, one of whom actually specializes, if that is the right word, in "philosophy of meteorology". I can't wait to bend her ear on this one.

djr said...

Okay, I have to say it: despite epistemological problems with scientific realism and the continually revisionary nature of scientific inquiry, one thing (natural) science has been and continues to be very good at is predicting and controlling phenomena. Even climate scientists (okay, well, the honest ones) admit that models are models and consequently uncertain and always imprecise. What seems very unlikely is that the science is just completely wrong, both about its broad predictions and its broad causal hypotheses.

Even if one grants that skepticism about the causal hypotheses is warranted, it doesn't seem to follow that the best 'normative conclusion' is that we do nothing at all to protect the environment from the threats that it may face. Unless there is a good possibility that the science could be wildly wrong, then appeals to uncertainty seem pretty academic and, at the very least, far from justifying inaction. I agree that scientists themselves are probably not the best people to ask about what exactly we should do, but given that there is a virtual unanymity among climate scientists that global warming has been due to human causes and that it is likely to have large-scale effects that we can avoid, people who favor inaction have the longest arguments to make.

That said, a realistic appraisal of the science should lead people to calm down a little bit and quit with the apocalypticism. I would agree that many of the people screaming about the impending doom of global warming are overreacting. But I'm not sure how much worse that overreaction is than complacency.

If the 'normative conclusions' of scientists trouble you, perhaps you would be more likely to be persuaded by the normative conclusions of John Paul II. He certainly did not favor inaction.

Vitae Scrutator said...

When you say that "it doesn't seem to follow", I'm not entirely sure what you mean. Are you suggesting that there's a logical connection between the discovery that the climate is gradually warming and a decision on somebody's part to "do something" about it? I guess I'm not good enough at logic to see what that connection is. But I do know enough about logic to know that nothing that I said entails that my own recommendation is that we do absolutely nothing at all--my complaint is about the widely accepted view that what we need to do is relatively clear.

There are a number of questions at issue here:

(1) Is the climate warming in a way that is unusual, that is, not in keeping with long term trends?

(2) If the answer to (1) is "yes", is this change in the trend due primarily to human activity?

(3) If the answer to (1) is "yes", is there anything that we can do to reverse the present trend, regardless of the answer two (2)?

(4) If the answer to (2) is "yes", is there anything that we ought to do to change the present trend?

(5) If the answer to (3)/(4) is "yes", how do we go about deciding upon the best course of action?

These are by no means simple questions. I take it that the consensus--for now, anyway--is that the answer to (1) is "yes". But it is a fragile consensus--the data are not clear, for one thing, and we know next to nothing about really long term trends in temperature and what the causal processes at work are. All we really know for sure is that we produce a lot of carbon dioxide and methane, and those are "greenhouse gases". Everything else is just typical hypothesis formation.

The answer to (2), again, seems to be "yes", again by a fragile consensus. It's not exactly what follows from the fact--already well known to ecologists--that organisms have an impact on their environments.

The answers to the other questions (especially (5)) are extremely unclear--there is no "scientific" procedure for answering them (with the possible exception of (3)), and scientists, in particular, are in some ways the least qualified to answer them, and yet it is primarily scientists and fans of scientism who are making the policy recommendations in these areas.

Question (5) raises the most difficulties, it seems to me. Some folks seem to think that if we had just signed the Kyoto treaty things would already be getting back to "normal", whatever that is supposed to be. It's worth noting that many of the signatories to Kyoto have still done none of the things that they agreed to do in that treaty, and yet popularly the moral onus continues to fall on the US, principally because (a) we didn't sign on and (b) we're big polluters. There's a lot of stuff at stake--not just for the US, but for most of Asia and Africa--and it hardly seems fair for a small number of first world countries to be making decisions that affect the worldwide economy. Some folks appear to think of things like the Kyoto treaty as somehow nothing but good for the third world, but that is a rather myopic view. I suppose from one point of view it's always good if you can get an economic giant to do your bidding, but sometimes pushing giants around can cause unwanted trouble for little people, and at that point the Schadenfreude ceases to be worth it.

So while I in no way advocate doing absolutely nothing at all about our contribution to world pollution, I continue to maintain that we so far have no real data to help us to decide what it is that we ought to be doing, and I remain skeptical that there's really any sort of data that could do that for us. Hency my worry about the scientistic view that if we just hand things over to the nice scientists they'll tell us what we should do. That kind of Star Trekky view of the world is long overdue for toppling.

djr said...

Well, when I said that it didn't seem to follow, that was my attempt at politely saying that I think it didn't make sense. It didn't then. It's clearer now, but I think your position is still basically an excuse for inaction. Most importantly, your claims about the science are strong enough that, if you really expect me or anyone else to accept them, you will need to do more than assert that there is some lack of consensus or some flaws in an area of science in which you have no qualifications. You will need to support your claims with reference to the science itself; so far you've limited yourself to abstract considerations about scientific theories in general and empty assertions about the particular theories in question.

The answer to question 1 among climate scientists is a virtually unanimous 'yes.' The answer to number 2 is a less unanimous, but still resounding 'yes.' There are a number of competing answers for the third question, but there are enough of them to provide starting-points for decisions. Question 4 is only loosely relevant, since we can have plenty of good reasons to do something without being obligated to do something; perhaps the question would be more pertinent if it were reformulated negatively, as a question about whether there is some reason that we ought not to do something. Question 5 is the big question, of course, and I have no disagreements with anything you've written here about the Kyoto Protocol and the silliness of trusting scientists to be good politicians and all of that. Scientists shouldn't be the ones making political decisions, of course, but so far the people who should be making the decisions haven't been able to spend time debating real alternatives because too many of our politicians are paid to continue to deny that global warming is any kind of problem at all.

So, short of any actual substantiation of your assertions about the state of climate science, it still "doesn't seem to follow" -- that is, it doesn't make sense, which is to say, it is a mistake -- to fail to do anything much about the problem. You claim that you don't advocate inaction, but I can't quite see how your position leads to anything except demands that climate science reach some impossible scientific ideal of absolute certainty before we bother to get really serious about it.

Your webpage is still broken.

Vitae Scrutator said...

but I think your position is still basically an excuse for inaction

Ah, to be young again, with the energy to stick my fist into the air and yell slogans at the establishment!

I prefer to think of it as an argument for sanity in the face of hysteria.

Most importantly, your claims about the science are strong enough that, if you really expect me or anyone else to accept them, you will need to do more than assert that there is some lack of consensus or some flaws in an area of science in which you have no qualifications.

You have rather seriously misunderstood the nature of my claims. I have said nothing at all that requires any special expertise in any of the sciences. Scientists have expertise to tell us what the facts are; they have no special expertise to tell us what follows from the facts that they discover. I am as qualified as anyone to speak to that. Indeed, when it comes to what doesn't follow from the facts, I'm somewhat more qualified, apparently, than many scientists, who seem to think that all they have to do to mandate some kind of governmental policy is point to a thermometer.

empty assertions about the particular theories in question

No offense, now, but you really need to acquaint yourself with the literature before you start making remarks like this. The dispute that I'm talking about is a well known one, the arguments on both sides having circulated for quite some time. The "empty assertions" that I make are in fact just reminders to a knowledgeable audience that the case for the louder side has yet to be made, in spite of all the posturing on that other side. The fact that you think the answers to (1) and (2) are "virtually unanimous" just serves to underscore how much catching up you have to do. Make it a point to get your news from sources other than The Nation.

If we add to this the fact that you continue to think that my point is that we ought to do nothing, I think that at least part of your homework should include re-reading what I actually wrote and thinking about it a little harder.

djr said...

Well, at least you fixed your webpage.

I'd appreciate it if you could point me towards any documents in which a non-negligible number of actual climate scientists dissent from the views which the climate scientists I've read (most recently, A Barrie Pittock, but also virtually everything I've ever read by any climate scientist) insist are well established and agreed upon by virtually all climate scientists. If the sources I've read are just lying about a simple matter of fact (as agreement within a given community can be considered), then it should be pretty simple for you to demonstrate that to me. I realize, of course, that plenty of non-scientists pontificate about the problems with the climate science and about what's really going on, but just like I don't trust atheists to explain Christian theology to me in an authoritative way, I don't trust politicians and science fiction writers to tell me about the validity of particular scientific inquiries in an authoritative way.

I've read what you've written several times, and despite your protestations, I can not conclude other than that your case rests not on the qualifications of scientists to tell us about the normative implications of their science, but about the reliability of particular scientific studies. I agree with you about the role that scientists should have in political discussions about what courses of action we should take, but I still find your skepticism about their scientific findings overblown. If I'm really just uninformed, then you'll no doubt have an easy time pointing me in the direction of better information.

But who am I kidding? Paul Halsall demolished you already anyway.

Vitae Scrutator said...

But who am I kidding? Paul Halsall demolished you already anyway.

Yes, and using his usual methods, I might add! But that's half the fun of hanging out with him.

Homily for Requiem Mass of Michael Carson, 20 November 2021

  Readings OT: Wisdom 3:1-6, 9 [2, short form] Ps: 25 [2] NT: Romans 8:31b-35, 37-39 [6] Alleluia verse: John 6:39 [...