Appearances to the contrary, Mr. Guggenheim's movie is not really about Al Gore. It consists mainly of a multimedia presentation on climate change that Mr. Gore has given many times over the last few years, interspersed with interviews and Mr. Gore's voice-over reflections on his life in and out of politics. His presence is, in some ways, a distraction, since it guarantees that "An Inconvenient Truth" will become fodder for the cynical, ideologically facile sniping that often passes for political discourse these days. But really, the idea that worrying about the effect of carbon-dioxide emissions on the world's climate makes you some kind of liberal kook is as tired as the image of Mr. Gore as a stiff, humorless speaker, someone to make fun of rather than take seriously.