Despite the Democratic presidential contender’s prominent role in the film, most reviewers are urging people of all political persuasions to go see “An Inconvenient Truth,” Al Gore’s documentary about global warming, and many columnists are saying the same thing.

The Timberland company had the same reaction. The Stratham-based international manufacturer, which has voluntarily committed to being carbon neutral by 2010, has invited everyone to see the movie for free as their guest at The Music Hall when it opens there on Thursday, Aug. 17 at 7:30 p.m.. Timberland will also host a panel discussion afterward.

“We’re doing this to bring about awareness around the issue, but also to identify solutions for all of us to reduce our impact on climate change,” says Betsy Blaisdell, manager of environmental stewardship for the company.

Trevor Bartlett, film series manager at The Music Hall, notes that it’s going to be a very full night. “There will be valet bike parking, we have an eco-artist who will be providing an installation, outside or in our lobby depending on the weather, plus a post-show reception at the Portsmouth Brewery after the panel discussion,” he says.

The film is almost entirely based on a slideshow presentations that Gore has been carrying around the globe since his defeat to George W. Bush in 2000.

While moments of cutting away to Gore’s personal motivation and commitment to the topic admittedly make it feel like a bit of a campaign film, the thrust of the global disaster is presented with a systematic straightforwardness that’s almost elegant in its simplicity. You don’t need to like Gore, or even trust him, to be scared to pieces.

Yet Gore is calm, rational, logical and even amiable despite his message, which gives him and the science he’s toting a credibility that comes in handy when he eventually points out it’s not too late to make a difference, if each one of us is willing to take a little moral responsibility and change our behavior.

If that sounds heavy handed, the film is not. It wouldn’t work half as well without the personal backstory Gore reveals throughout, nor the humor, which is used sparingly but to great effect, as when he shows a cartoon clip to explain global warming. The clip is from a “Futurama” episode in which Gore guest starred as himself, claiming to be the inventor of the environment and the author of both “Balance of the Earth” and the more popular “Harry Potter and the Balance of the Earth.” 

For those who’ve been paying attention, the presentation is a compelling review of the facts. For those who have recently tuned in, its alarmingly realistic picture of the future, including the prospect of a hundred million environmental refugees, is guaranteed to leave you feeling green.

The film will also play on Friday and Saturday at 7 and 9:15 p.m., when admission is $6.