Hot air: an Inconvenient Truth, Al Gore's new documentary about global warming, is intriguing, but fails to convince in the end.

Former vice presidents of the United States usually follow one of two paths upon leaving office: run for the office of the presidency and, achieving that post, move on to create their own presidential legacy, or fade into obscurity (also considered to be "Plan B" for those who fail at option one). Most vice presidents end up in obscurity. How many people today think about Spiro Agnew or Walter Mondale?

Al Gore chose to run for the presidency. But after failing to defeat George W. Bush, he has refused to follow "Plan B." Instead, he has gotten into the business of documentary filmmaking, and his first effort, An Inconvenient Truth, has been playing at theaters over the summer months. The film is intended to warn Americans of the dangers of global warming.

It's not exactly a summer blockbuster, but because it was both made by and features Gore, it exudes a certain novelty. It is unusual, perhaps even unprecedented, to see a former vice president give a presentation on the big screen. It is a humanizing experience. Under the glare of the media, all vice presidents, while in office, are reduced to simple, wooden caricatures of men. They become the sidekicks to the presidential superheroes and the stigma of that caricature is hard to shake. Gore, though, does shake it, revealing himself over the course of An Inconvenient Truth as a thoughtful and intelligent, and sometimes engaging, speaker. For all that, though, the film still fails.

The Fragile Atmosphere

Gore begins his presentation with a simple argument. The Earth itself is huge and resilient. It resists man's puny efforts to change and modify the environment. But this is not true of the atmosphere. Gore points out that the atmosphere is really quite thin and that, in contrast to the rest of the Earth, it is therefore relatively fragile. The implication is that human activity can have a drastic effect on the condition of the atmosphere. Naturally, Gore thinks we are having that effect and that in the near future, we will pay for our profligacy through runaway global warming.

The engine of this warming, according to the global-warming hypothesis, is carbon dioxide. Gore points out that atmospheric carbon dioxide is increasing and that this will lead to rising temperatures worldwide. But will it? There are scientists who disagree with this assessment. Among them is Tim Patterson, paleoclimatologist at Canada's Carleton University. In testimony to Canada's Commons Committee on Environment and Sustainable Development, Patterson explained that there is evidence that high carbon dioxide levels do not necessarily lead to high temperatures. "In fact," Patterson testified, "when C[O.sub.2] levels were over ten times higher than they are now, about 450 million years ago, the planet was in the depths of the absolute coldest period in the last half billion years."

There is no place for inconvenient alternate views in An Inconvenient Truth. There is, however, plenty of room for rhetoric. Gore's presentation is peppered with charts and graphs, but these are usually devoid of numbers. When talking about C[O.sub.2], for instance, Gore displays a chart showing a steep rise in C[O.sub.2] levels, but there are no numbers on the chart to put the data displayed into perspective. Moreover, there are scientists who disagree that C[O.sub.2] increases drive warming, arguing instead that such increases followed temperature increases (see article on page 10). It is a controversial point, but it casts great doubt on the entire anthropogenic (human-caused) warming theory. Gore does not reference this work.

Scare Tactics

The film is punctuated by periodic sojourns into Gore's reminiscences. These are interesting and sometimes compelling. When Gore tells the story of how his son was struck by a car, you can't help feeling sorry for him. His pain as a parent who nearly lost a child is obvious. It is this event, he says, that motivates him to try to save the world from global warming. His son's life was saved; now he must try to save the planet for all children.

Unfortunately, Gore's story about global warming doesn't reverberate as genuine, as did his story about his son. As the film progresses, for instance, his warnings get more extreme. It really starts to get noticeable when the subject of hurricanes comes up. Gore suggests that Hurricane Katrina was devastating because it was powered by global warming. He then says that because of global warming "there have been warnings that hurricanes would get stronger." But claims about the supposed link between global warming and hurricane strength and frequency are highly contested. Dr. William Gray heads Colorado State's Tropical Meteorology project. Discover magazine calls him the "world's most famous hurricane expert." He says that people who link hurricane strength and frequency to global warming don't know what they are talking about: "The degree to which you believe global warming is causing major hurricanes to increase is inversely proportional to your knowledge about these storms," he said in an interview with Capitalism Magazine.

As the film progresses, Gore exaggerates more and more. By the end of the film he is claiming that if nothing is done to stop global warming, the oceans will rise by some 20 feet. As he speaks, an animated map of the Northeast shows the ocean pouring over the coast, inundating New York City. Yet even the UN's Intergovernmental Panel on Climate Change is not that pessimistic, noting that over the 20th century, sea levels increased "at an average annual rate of 1 to 2 mm." That's only 1 or 2 centimeters in a century. The IPCC predicts a sea-level rise of from 3 to 14 centimeters by 2025, not enough to flood New York. Gore's movie, though, is 2004's disastrous Day After Tomorrow global-warming scare flick all over again, but this time without the special effects.

Credibility Gap

In the end, the film loses its credibility by resorting to ever more frightening and unlikely scenarios designed to galvanize the audience into action. But this is in keeping, in a sense, with Al Gore, the man who in a 1999 interview with Wolf Blitzer on CNN said, "During my service in the United States Congress, I took the initiative in creating the Internet." He might have been involved with some legislation that affected the development of the Internet, but he certainly didn't create it.

In the same way, Gore exaggerates throughout An Inconvenient Truth. About halfway through, for instance, he tells the story of visiting the Antarctic where a team of scientists is taking ice cores. Examining one of the cores, Gore recalls the scientist with him pointing at the core and saying something along the lines of "see fight here, this is where Congress passed the Clean Air Act." As with his Internet claims, there is likely a kernel of truth here. Gore probably did talk with a scientist about the cores and the subject of the Clean Air Act probably came up. There is no basis for accusing Gore of lying about the broad outlines of the story. But to say that there is a clear line in an ice core demarcating the advent of the Clean Air Act is nonsensical. The naked eye can't pick that out of an ice core.

So, in the end, should you see this movie? Yes, if you're interested in the subject and well girded with true facts about global warming, but wait for the DVD. It's not worth the price of a movie ticket.