I recently went with some friends to see Al Gore’s “An Inconvenient Truth,” a one hour and forty minute movie by Gore on the problem of Global Warming. Rotten Tomatoes gave it a 92% rating so I knew that the movie couldn’t be a total dud. Here are some of my reflections.
I found the movie interesting and even funny at times. The first thing that has to be appreciated about this movie is that this is a political movie and not a documentary. That said, it is not one long partisan diatribe against the Republicans, although the obligatory cheap shots are there. The movie clearly has two objectives. One is to persuade you that we are in a global environmental crisis and we need to take action. The other is to introduce you to a more human and idealistic Al Gore than you encountered in the 2000 presidential election. (Can you say “Gore 2008?”) The movie works well, especially if you are inclined at all to take what the movie says on face value. The problem is when you fact check and begin digging deeper than face value.
There is no question the earth’s temperature is getting warmer. The questions are about cause and effect. Gore insists that the emission of green house gasses are THE cause of global warming. He asserts a cause and effect relationship between carbon dioxide and temperature. He shows a graph that indicates how levels of carbon dioxide and temperature have paralleled each other for about 600,000 years. However, the graph is too compressed to show how temperature and carbon dioxide track with each other over a few centuries or even a few millennia.
This is where it is important to remember the difference between correlation and causation. Two variables may vary together but they may have no impact on each other. That is correlation. When I take a road trip, the fuel gauge on my car drops toward empty as the odometer on my car turns ever higher. Is the declining fuel causing my odometer to turn or is the odometer turning causing the fuel to drop? Clearly neither is the case yet they correlate with each other. The reason for the change in both is a third variable: The car is being driven. Pushing this analogy a little farther, it is possible to imagine letting the engine idle for hours. The fuel tank would empty without ever changing the odometer. It is also possible to kill the engine and power the car by other means (pushing it or pulling it), which would change the odometer without affecting the fuel. Therefore, it is insufficient to show two variables correlating together and conclude any casual relationship. The precise nature of the relationship between all variables has to be established.
None of the above should be taken as denial on my part that there is some casual relationship between carbon dioxide and temperature change. The problem is that as either the temperature or levels carbon dioxide change they trigger a host of other ecological changes that quickly multiply into an enormously complex system of variables all having iterative affects on each other. Gore gives a short presentation of a theory based on two variables (greenhouses gasses and temperature) shows a correlation, and then demands that the audience accept unequivocally the direct causal relationship of greenhouse gasses on temperature. It just isn’t that simple.
Near the beginning of the movie Gore showed a chart that indicates the average temperature over the past 1,000 years. It shows an enormous spike over the last century or so. Gore ridicules those who say that there is a cyclical nature to these things. Yet if we go back 3,000 years looking at temperatures based on studies of the Sargasso Sea, we find that we are actually emerging from a mini-ice age that began about 1,000 years ago. The chart below shows that while the temperature has been rising, our global temperature is still below the average for the past 3,000 years. Furthermore, the changes are not nearly as abrupt (at least not yet) as they have been in other times over the past three millennia.
Also not acknowledged in Gore’s presentation is the fact that while the earth has warmed over the last century, it did it's most significant warming from about 1910-1940 and the global temperature actually declined from 1940s-1970s prompting scientists to declare that we were entering an new ice age because of carbon dioxide emissions and “greenhouse” gasses! Here is one chart of the average temperatures over the last century:
Since Carbon Dioxide levels have been rising steadily over the last 150 years, there clearly is not a one-to-one relationship between Carbon Dioxide and global temperature. Is there any other variable that correlates better to temperature change? Yes. Sun activity.
The sun is not a perfectly stable generator of heat. The chart below charts the levels of solar irradiation with average global temperature. (The growth in Carbon Dioxide (CO2) is given in the lower right of the chart.)
In addition to this data, there is evidence that both Jupiter and Mars are experiencing planetary warming as well. (See Global Warming on Other Globes) None of this proves that irradiation is the primary cause but the chart above at least suggests a strong relationship. It is consistent and reasonable to assume that irradiation may be the driving factor.
Gore makes a host of other claims that are unwarranted. For instance, he suggests that sea levels will rise twenty feet when the scientific literature suggests that the worst case scenarios would lead to a rise of less than three feet. He talks about melting of the polar regions over the past few decades without pointing out that this melting has been going on for more than a century. He attributes the increased number of hurricanes to global warming. Yet the United Nations Intergovernmental Panel on Climate Change (IPCC) (who the media likes to tout as having the final word on climate change despite the fact that most of the scientists are not climatologists) wrote recently, "Changes globally in tropical and extra-tropical storm intensity and frequency are dominated by inter-decadal and multi-decadal variations, with no significant trends evident over the 20th century." (See Summary for Policymakers.) Furthermore, in Global Warming Not Featured in New Hurricane Study, Patrick Michaels shows that present global warming models predict sea-surface temperatures that should lead to a decline in hurricanes, not their increase. Either the hurricanes are being caused by global warming the models are wrong, or the hurricanes are not being caused by global warming and he models are right. You can’t have it both ways.
Finally, Gore goes to the “devastating” clincher that climate change alarmists bring out to silence all further dissent: Scientific consensus. Gore mentions a review of over 900 peer reviewed articles that shows that not one of them disputes human caused climate change. Therefore, anyone who would dissent is a flat earth fringe type who will never be convinced and are they are likely dupes of evil corporations. (He draws a direct comparison of the skeptics to those who doubted the effects of cigarettes.) Of course, what Gore fails to point out is that while scientists universally agree that there is a human component to climate change, there is a wide array of opinion on how much it affects it, ranging from negligible to 100%. Any non-scientist visiting the library or surfing the web can see that the climatologist community not affiliated with the IPCC divide into a number of different schools of thought on what is happening.
Ironically, Gore points to Mark Twain’s quote that goes something like this: “It isn’t what we don’t know that gets us into trouble. It is what we know that isn’t so that gets us into trouble.” Never was a truer word spoken about the climate alarmists who “know” what is causing global warming! Gore points to a grade school teacher he had who maintained that, according to scientific consensus, Africa and South America never connected as one land mass. Scientific consensus was wrong. I really like this quote by climatologist George H. Taylor, past president of the American Association of State Climatologists:
But even if there actually were a consensus on this issue, it may very well be wrong. I often think about the lives of three scientists who found themselves by themselves, on the "wrong side of consensus." There have been many in the history of science, but I singled out Alfred Wegener (Continental Drift), Gilbert Walker (El Niño), and J. Harlan Bretz (Missoula Floods). None is well-known now among members of the public, and all of them were ridiculed, rejected, and marginalized by the "consensus" scientists -- and each of the three was later proven to be correct, and the consensus wrong. As a well-known writer once said, "if it's consensus, it isn't science -- and if it's science, it isn't consensus." (A Consensus About Consensus)
The climate change alarmists consistently use the trump card of consensus to defame and ridicule any dissenters. This demagoguery was used in the past and it will be in the future.
Related to the consensus trump card is the “who are they working for” question. As I surf blogs and articles about this topic I see frequent observations about scientists receiving grants from this or that foundation or corporation. The conclusion is that because a scientist got funding from someone who may benefit from a particular finding, their research is to be dismissed out of hand. The fact is that all scientists get funding from somewhere and that funding may influence what they study but scientific research has to be published and explained well enough that other scientists can verify or falsify conclusions. The funding issue goes more to what is studied and what isn’t, rather than the facts in dispute in a particular study. The fact is, using Al Gore’s tobacco industry analogy, it is the alarmists who control the bulk of the funding dollars and peer reviewed journals, not the skeptics. The “who funded what ‘gotcha’ game” is a straw man.
Having said all this, the curious thing is that I kind of liked Al Gore in this movie. He was entertaining and I liked his idealism. I suspect that he has genuine conviction about his climate change concerns. I don’t think this is just cynical opportunism even if the movie’s “facts” are highly deceptive. Some of the possible changes that result from warming could indeed impact human populations. It appears that some already are. Natural habitats are changing as well. It is right to be concerned about these issues and asking what we might do about them. Pollution is never a good thing, regardless of whether it is causing global warming, and finding renewable energy resources would have tremendous positive economic benefits for the entire planet. From what I have read, I think the movie is overly optimistic about how much we can change emissions with existing technology. Still, that doesn’t mean we shouldn’t do what is reasonable and prudent toward a cleaner environment and renewable energy.
If you want a first rate movie that takes you inside the climate alarmist’s worldview, then this is an exceptional movie. If you want some insights into what makes Al Gore tick, then the movie is worth seeing. However, if you want to know about climate change, then beware that you are watching a highly deceptive well put together political commercial.
(You may also want to read Inconvenient Truths Indeed.)
Update: Wikipedia has an excellent presentation about solar varition as a cause of global warming.