Tuesday, April 20, 2010

Political, Not Scientific

I'm up and running on a promised series of posts each of which is a confident and certain statement about the threat of anthropogenic global warming. This confidence and certainty are all the more startling because of my first claim (in yesterday's post), which had to do with the fact that this issue involves a great deal of debate and controversy. It is precisely because there is such a diversity of opinion--even among the appropriate scientists--about human-caused global warming that my claim to be able to make several statements with certainty should be at least provocative.

I'll trust that my first statement passed muster, that no one is really willing to argue logically and evidentially (as by a willingness to hear from every scientist) that no scientist doubts or harbors skepticism about the idea that human-caused warming is occurring at an unprecedented and dangerous rate. My second certain statement is a corollary of the first...
The global warming alarm as cast in the various media is not primarily scientific but political.
This statement likewise seems so obvious as to require little support. The issue became part of our collective awareness through a politician, not through a scientist. The issue is kept before us by politicians and by political journalists. Indeed, the only confusion on this point likely stems from the frequency with which those politicians appeal to science--"all scientists agree that anthropogenic global warming is occurring at a dangerous rate." This claim we know is untrue, and so can see it as a mere ploy, an attempt to disguise a primarily political discussion as a scientific one.

I hope that even those of you who are not scientists can as readily (as those of us who are) see that though scientific evidences ought to ground our conclusions about the validity of anthropogenic global warming, such evidences have become a minimal part of the rhetoric associated with this issue.


Jordan said...

OK, so I'm totally confused on this issue. All scientists that I work with that I've asked about this issue have all said that AGW was "settled science". They would agree that the issue is political and not scientific ... because the science is already settled and the only thing remaining to do is to convince the backwards, red-neck Republicans.

How do we know that there is a lot of debate as to the core of the AGW issue? The only possible thing I've heard was a single scientist at a conference I was at, who worked at NIST I think and was working on space-based CO2 sensors, said that he though much more science needed to be done to really know the details of what's going on. Other than that one scientist, everybody I've talked to said it was settled and in favor of AGW. I'm confused.

Rick Gerhardt said...

Hi Jordan:

There are several simple explanations for your experience (and I don't know which, if any, is right). Either the sample of scientists with which you've talked is skewed toward those who actually study and accept AGW, or some of them are unwilling to be perceived as being skeptical of the reigning view, or some of them haven't really considered the evidence and are simply rubber-stamping what they have heard.

Some general trends can be identified... Meteorologists, who spend their time looking at weather patterns at too short a temporal scale, tend to reject AGW. Those climatologists who examine the thermal data at historical scales (which I would argue is also too short a scale) tend to be the vocal proponents of AGW. Paleo-climatologists (who look at things from much longer scales) are almost unanimous in recognizing periods in Earth's history during which the Earth has been much warmer (and yet life persisted, albeit not human life). Theoretical physicists and chemists are all over the map, and any good statistician would tell you that the complexity of the issue (the number of factors involved) precludes any predictive model from having any credibility.

I chat with a wide cross-section of scientists (generally in a fairly safe, confidential forum) and know of the wide diversity of scientific opinion about the issue. But my main point was that even without such knowledge, you can and should be suspect of anyone who claims "all scientists agree..." (about almost anything) without clearly articulating the very same evidence that would lead all scientists to such a conclusion.

Hope that helps, and thanks for reading.

Rick Gerhardt said...


By the way, even if there were no debate among scientists (which there most certainly is), it would not prove AGW (or anything else). It is a form of the ad populum fallacy to claim that something is true because everyone believes it. Moreover, the history of science is full of times when virtually all scientists believed a paradigm (phlogiston chemistry, Newtonian physics, the immovability of the Earth's crust) just before a breakthrough was to completely reorder the understanding (oxygen chemistry, general relativity, plate tectonics).