Hollywood time is not geological time.

• Position: Your Life

The cataclysmic ice age scenario depicted in "The Day After Tomorrow" gets the mechanics of global warming mostly correct, but wildly exaggerates the speed at which it might occur, reveals a Duke University, Durham, oceanographer who studies North Atlantic Ocean currents.

The type of global climate change that happens in the movie--where global warming diverts warm ocean currents and abruptly plunges the world into a new ice age--possibly could happen in real life, "but it would take many, many decades or even a century or more," assures Susan Lozier, Truman and Nellie Semans/Alex Brown & Sons Associate Professor of Earth and Oceans Sciences at the Nicholas School of the Environment and Earth Sciences. "Hollywood time is not, obviously, the same as geological time."

Despite its inaccuracies, Loziar thinks "The Day After Tomorrow" may prove beneficial to the policy debate about global warming by raising public awareness of the oceans' role in climate and weather fluctuations. "When people think about global warming, they think about the whole world getting warmer due to greenhouse gases. They may not realize that some parts will get warmer and some will get colder; some will get wetter and some will get drier, due, in part, to changes in ocean currents."

The oceans store a tremendous amount of heat from the sun and their currents act like a giant conveyor belt, redistributing that heat around the globe, she explains...