★★★ ½

At one point in An Inconvenient Sequel: Truth to Power, the follow-up to 2006’s Oscar-winning documentary An Inconvenient Truth, former vice president Al Gore quotes poet Wallace Stevens: “After the final no there comes a yes, and on that yes the future world depends.” And it is Gore’s lifelong quest to get resistant cities, countries, and continents to say yes to renewable energy and no to fossil fuels in order to drastically curb global warming and literally save the planet.

Much of the new film follows Gore as he tirelessly travels from country to country for his Climate Leadership Training seminars, showing its eager participants how dire global warming has become in the ten years since he gave his now-famous slideshow presentation. He persuasively connects the dots between melting glaciers in Greenland to rising sea levels and flooded streets in Miami, and between record-level heat and drought around the globe to “Noah-like storms” and the spread of the Zika virus. It’s all done in an easy-to-digest but compelling manner, and Gore’s passion is infectious.

Directors Bonni Cohen and Jon Shenk smartly make their documentary as much about Gore as climate change. The “recovering politician,” as Gore jokingly describes himself, adds levity throughout with folksy humor, and even poses for a good-natured photo beneath a GOP sign with the Republican mayor of Georgetown, TX, “the reddest city in the reddest county in Texas,” which now uses renewable energy for 90 percent of its power instead of fossil fuels. Gore is treated like royalty everywhere he goes, and that includes Paris, where he attends the 2015 Climate Change Conference. One major holdout at the conference is India, whose leaders are averse to switching to clean energy and reluctant to sign the agreement. But Gore won’t take no for an answer, and so he calls up SolarCity CEO Lyndon Rive to make a strategic deal with India. Needless to say, Gore eventually gets the yes he wants, although his triumph suffers a setback when President Trump withdraws the U.S. from the Paris Agreement. But the ever-resilient Gore is undeterred, and An Inconvenient Sequel ends with the following emblazoned onscreen: “If President Trump won’t lead, the American people will.”

Gore emphasizes that the war on global warming can be won if ordinary citizens rally and demand that their leaders invest in renewable energy. But, he admits, it’s not happening fast enough. “The next generation,” he says, “if they live in a world of floods and storms and rising seas and droughts and refugees by the millions escaping unlivable conditions, destabilizing countries around the world, they would be well justified in looking back and asking, ‘What were you thinking?’”

It’s a good question, and one Gore powerfully puts forth in his inconvenient new film.