Tuesday, July 25, 2006

An Inconvenient Truth, or a Convenient Pack of Deceptions?

OK, I had a momentary lapse of sense and went to see Al Gore's movie, An Inconvenient Truth. Let me get the accolades out first: Al Gore is actually good on camera, and manages to crack a few good ones. The movie will, I suspect, cement the center and left Democratic support for general Democratic party policies and maybe even help Gore if he wants to try another run.

But I am furious over this movie. Absolutely furious. The main prop is the graph of CO2 and temperature over a run of about 650,000 years. This is the well-known temperature, carbon dioxide record recovered from glacial ice cores. Gore makes the most out of it; the chart of the two lines covers the entire screen, and the correlation between temperature and CO2 is obviously close to 1. Then comes the finishing touch (or the grand deception) which is to add the recent CO2 increases (the last 50 years or so) and let the audience draw the obvious and inescapable conclusion that the temperature line will follow the CO2 line upwards into uncharted and cataclysmic territory. Hey, if temperature has been so closely correlated with CO2 over 650,000 years, the pattern is certainly not going to change now is it?? The overall effect of the presentation is quite convincing, and it sets the tone for scary discussion of the climate crisis for the rest of the movie.

My alarm bells started clanging so loudly at this point that I thought I was going to be asked to leave the theatre.

Hmmm....Gore makes a lot out of his college experience in this movie. Did he ever take a course in statistics where they warned about not drawing causal conclusions from mere correlations?

There are a couple things to note about Gore's beloved but deceptively used long term CO2/temperature relationship. First, more careful statistical analysis of the data shows quite convincingly that changes in CO2 concentrations FOLLOW changes in temperature, by something like a lag time of 1000 years. How about that for an inconvenient truth, Al? Don't you think maybe you should have mentioned that?? So some third unknown factor is driving temperature, and then CO2 follows. The reasons for increases in CO2 concentration to follow increases in temperature are varied, but one big one is that the oceans hold less CO2 at higher temperatures. Think of a bottle of Coke on a warm day -- if you shake a bottle, will you get a bigger explosion (release of CO2) on a warm day or a cold day? How about that for a second inconvenient truth, Al?

The biggest issue with these data is, of course, what causes the temperature to increase first, and, I will admit, if there is any subsequent positive feedback of the induced increase in CO2 on temperature. That would be a valid way to put the issue. But if you do that, the point of the movie is going to be lost, right? I mean, how can you say: Well, we don't really know what causes these temperature fluctuations over the last 650,000 years, and all we can really say for sure is that changes in CO2 are caused by the temperature change, not the other way around. But let's not let that get in the way of letting us tell you that we know for sure what has been causing the temperature increase of the last 50 years, and that is the increase in CO2.

I don't know how any self-respecting scientist can let Al Gore get by with such statistical deception. To use that chart in such a deceptive fashion, drawing the CO2 line for current times into the stratosphere and just inviting people to draw the temperature line behind it, that really hits a new low. I am sure that the Hanover audience included a lot of PhDs. Are they so blinded by the propaganda that they don't want to go out and do a little independent thinking??

As I walked into the Hanover theatre, it felt like I was walking into a local Democratic Party get-together. These are all the same people who accuse Bush and Cheney of lying about WMD. Where is their outrage over Al Gore's most convenient and deceptive abuse of the historical climate record? Where is their outrage over the convenient leaving out of the well-accepted finding that CO2 lags behind temperature in that record? Where is their outrage over the convenient lack of mention that the relationship between the oceans and the CO2/temperature record is really critical?

The hypocrisy in the world is going to kill me.

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