The Day After Tommorow Fact of Fiction?

<Tab/>I watched a movie called The Day After Tomorrow. It's mostly about what the world would look like if the greenhouse effect and global warming continued at levels that they resulted in worldwide disaster. It's about a paleoclimatologist, Professor Hall, who tries to save the world from the effects of global warming, when the city was scared for the chilling beginnings of a new Ice Age. In addition to all of the other challenges Dr. Hall faces, he's also going against the flow as the people racing south to warmer climates, and he's nearly the only one that was going north…