An Inconvenient Truth is the summer's only indispensable movie, deserving the poring over that The Da Vinci Code got. It's a concert film of a lecture by former Vice President Al Gore on the subject of the fate of the human race.

Aiming for simplicity and entertainment, Gore aligns an array of facts that will be very hard to refute. He focuses on nonpartisan ways to avoid the unthinkable: the melting of the ice caps, the flooding of the coasts, the spread of tropical diseases, the famines that we will have difficulty imagining, let alone enumerating.

The surprise is that it's an entertaining show. It's witty. It's playful. Gore is a huge fan of Mark Twain, taking a Twain quote as an epigraph: "What gets us into trouble is not what we don't know. It's what we know for sure that just ain't so."

In person, Gore comes across looser and more amusing than he did during his candidacy. Today, he is a vastly different man than the strained, hesitant political candidate he once was. Perhaps it has occurred to him that the bulliest pulpit these days is a movie screen. If Gore is in the wilderness, it is in an Airstream trailer with all the hookups, a satellite dish and a smoldering barbecue.

At our interview, he is smooth, he is affluent, he looks 10 years younger than he did in 2000; he is dressed smartly in black clothes and sitting at a desk in a high level in a nice hotel in San Francisco (which is home base for his cable network, Current TV), with a twilight view of Twin Peaks behind him and a half a bottle of Heineken at his right hand.

METRO: Do you really believe we have only 10 years to avert disastrous global warming?

GORE: I do, I really do. Over the last 30 years, during the time I've tried to tell this story, there have been times when people said we only had 10 years, 15 years. I never had repeated that or paid much attention to that. Just in the last six months, some of the leading scientists in the world--who actually do know what they're talking about--have begun to say, we have less than 10 years in which to make a big start on dramatic changes, or we'll cross a point of no return. I do believe that. I respect these scientists; I've worked with them for decades. Now, I'm optimistic, because I believe that, in less time than that [10 years], we will make a big start.

METRO: Is there any such thing as a controversy over global warming anymore?

The debate's over. There are five points in the consensus. No. 1:

Global warming is real. No. 2: We human beings are mainly responsible. No. 3: Consequences are very bad, and we're headed toward catastrophe. No. 4: We need to fix it quickly. And No. 5: It's not too late. Those five points now support a global consensus. Exxon-Mobil doesn't agree with that, but they think the Earth is flat. On those five points the debate is really over. Now the debate is: What's the most effective way to solve it? How quickly can we solve it?

Is it true that you were on your way to New Orleans to film this movie when Katrina struck?

It was supposed to be a keynote speech to a conference of the 50 state insurance commissioners, and Davis was going to film it. It was on the subject of global warming's effects on hurricanes. I was supposed to speak Aug. 29 in New Orleans. Several days before, the whole thing was canceled. And they didn't reschedule it, because by then many of the commissioners were then wrestling with how they were going to cope with all the claims from Katrina. Ironic.

In 'An Inconvenient Truth,' you comment that you've seen evidence of climactic change at your family farm. Could you expand on that?

The spring is earlier, the fall is later and the winter is warmer. We have some evergreens that are now vulnerable to pine beetles that weren't vulnerable in the past. The colder winters used to kill the insects. The blooming season for flowering plants has moved up considerably. You're seeing mosquitoes at higher altitudes.

One story that seems a little underreported here on the coast are the terrible prairie fires ravaging Oklahoma and Texas.

There's been an increase in the number of major wildfires, in North America, South America, Asia, Europe and Australia. Warming dries out the soil, dries out the vegetation and increases the amount of lightning--which is not as well known--since heat puts more energy in the system. Thus the number of wildfires has expanded dramatically.

You were in office during the advent of the SUV, and the creation of oversized vans and Humvees. What were your feelings when you saw that automotive trend begin?

Dismay. I actually worked very hard to achieve an agreement between the government and Ford, GM and Chrysler on a partnership for a new generation of vehicles to achieve a three-time increase in mileage and a dramatic reduction in global-warming pollution. They took the money and made some progress, but when Bush and Cheney came in they immediately got to cancel any obligation to follow through on their part. Tragically, now GM and Ford are in economic trouble.

Where did you acquire the 'Futurama' excerpt for 'An Inconvenient Truth'?

My second-oldest daughter, Kristin, worked for Matt Groening for three years. She had heard me talking about global warming all her life, and she introduced that script element and was part of the small creative team that actually did that sequence. And because she was hired by Matt Groening, I got to know him. Then I was invited to do a cameo appearance as a disembodied head on the show. I made a couple of appearances. I was walking down Townsend Street [in San Francisco], and some business associates and I were on our way to the Paragon restaurant. Coming toward us are some men and women in their late 20s ... making the transition, I'm thinking, from punk rockers to responsible business persons. One of them recognizes me and shouts, "I have ridden the mighty Moon Worm!" My colleagues are saying, "Whaaaa?"

Are you a 'Simpsons' fan, too, then?

Absolutely. A wonderful show.

Now that you're on the film festival circuit, what can you recommend?

Tipper and I give out an award every year at the Nashville Film Festival, and this year it was the film Desire, about four young women who were sophomores in high school, from the little neighborhood in New Orleans where the Desire Street streetcar gets its name.

How do you handicap the upcoming election?

It's likely to be a Democratic wave. I don't know if it'll be big enough to change control of the Congress, because the threshold for change is now artificially and absurdly high, reflecting redistricting and the incumbent advantages. I don't really follow it closely enough to have an accurate prediction. I'm a recovering politician, on Step 9. [From the Alcoholics Anonymous 12 Steps: "Make direct amends to such people where ever possible, except when to do so would injure them or others."]

After watching the last five years of political life, have you ever dwelt on Henry Clay's most famous quote, 'I'd rather be right than president'?

[Mock sobs] Not until just now! I wasn't aware that was a binary choice. Clearly a "yes." Even if recent--there's no position comparable to the president's position, for the potential to bring about change. However, I faced a decision after the Supreme Court's decision as to what I was going to do with my life. I thought for a while I might run again, but I have found during the intervening years that there are other ways to serve, and I enjoy them.

An Inconvenient Truth, director Davis Guggenheim's documentary about Al Gore, opens Friday, June 9, at the Del Mar Theatre.

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