In theaters

THE DAY AFTER TOMORROW: Directed by Roland Emmerich, written by Emmerich and Jeffrey Nachmanoff, 124 minutes, rated PG-13.

In Roland Emmerich’s new disaster flick, “The Day After Tomorrow,” the first city to get cooked by global warming is Tokyo, which has been leveled countless times before by Godzilla, but which now gets pummeled into the pavement thanks to hailstones the size of Godzilla.

The giant balls of ice that crash through the city’s neon-charged skyline smash everything in sight – including the poor people running pell-mell in the streets – and hint at devastating things to come – like the events unfolding in Los Angeles, which quickly brings to mind Kansas in the film’s next money shot. Scores of tornadoes touch down and roar through the city, tearing away the Hollywood sign, bringing down the Capitol Records building and laying waste to the clutch of moronic reporters from The Weather Channel trying to cover these cataclysmic events for television. Before each of them gets creamed by the inevitable flying debris, they bravely provide comic relief, periodically screaming things like, “My God, there goes the Hollywood sign!” Or, “My God, this is awful!” Well, yes it is. Folks, Dorothy never had it this bad – and she was saddled with a gingham dress, a yapping dog and a wicked witch.

Since over-the-top destruction is the point of “The Day After Tomorrow,” Roland Emmerich (director of “Independence Day” and “Godzilla”) initially doesn’t hold back. The film’s first 20 minutes are a blast, more fun than you expect, with Emmerich having a grand time playing Mother Nature as he huffs and puffs and blows the world down.

Things get dicey for the director when his computer-generated storms reach New York City, where a mounting tsunami is about to overrun Manhattan. As the film’s great tidal wave rolls over the Statue of Liberty and slams into the lower Manhattan skyline, you sense this is it. Either Emmerich is going to have the nerve to alienate audiences by bulldozing those buildings left untouched by the terrorist attacks of 2001, or he’s going to have the good sense to back off. In a sense he does. No building falls, though millions do drown.

As written by Emmerich and Jeffrey Nachmanoff, “The Day After Tomorrow” takes the position that, thanks to the atmosphere being littered with greenhouse gases, major climate shifts have caused a series of storms that will soon plunge the earth into a new ice age. The film focuses on a handful of characters trying to survive the ensuing devastation until the worst is over – the day after tomorrow. Those people include climatologist Jack Hall (Dennis Quaid), who is in Washington fighting a Bushlike administration that refuses to believe the storms are the cause of global warning, and his 17-year-old son, Sam (Jake Gyllenhaal), who is stuck in the New York City Public Library fighting the storm with his classmate Laura (Emmy Rossum), a pretty girl on whom he has a crush.

Determined to save Sam if he can’t save the world, Jack actually and inexplicably believes he can travel to Manhattan in the short time before the Northern Hemisphere becomes a Frigidaire. Naturally, his car breaks down along the way, which means he must finish this foolish rescue on snowshoes. How that’s possible may make sense to Jack, but to us, it’s absurd.

Still, never mind. It’s best not to ask questions of logic from “The Day After Tomorrow.” It’s better to just go with it and enjoy the extra helpings of cheese Emmerich tosses into the story, such as the grave turn by Sela Ward as Dr. Lucy Hall. She’s Jack’s loving ex-wife, a woman whose glum mouth and sad eyes suggests it’s hell trying to protect her young cancer victim from catching the cold to end all colds, if you know what I mean.

“The Day After Tomorrow” is trash, but it’s not a cheat. It’s fast-paced and entertaining, particularly in its first hour, a film with good window dressing and an ecological heart that makes up for the so-so script grinding with stock B-movie characters.

Several scenes pack a terrific punch, such as when wolves, newly escaped from a zoo, go after Sam and his buddies in the Russian ship that made a wrong turn down Fifth Avenue. Or the scene that immediately follows when a deadly blast of subarctic air leeches into the city, freezing everything in sight and nearly nipping Sam in the tail. Or best yet when Americans are shown fleeing illegally across the border into Mexico in an effort to beat the looming deep freeze. It’s the film’s best, most outrageous twist, with our administration promising to forgive all Latin American debt should that country allow us in.

“The Day After Tomorrow” is high-strung, melodramatic hogwash, but it is steeped in a measure of scientific fact, Emmerich takes it as seriously as he can and his movie, as a result, delivers more provocative fun than you might expect.

Grade: B

Christopher Smith is the Bangor Daily News film critic. His reviews appear Mondays and Fridays in Style, 5:30 p.m. Thursdays on WLBZ 2 Bangor and WCSH 6 Portland, and are archived at RottenTomatoes.com. He may be reached at BDNFilm1@aol.com.