"If there was one like the A.D. 79 eruption, it would impact probably over a million people," Lopes said. "It (would) actually block some of the sunlight, so the global temperatures get a little cooler. That only lasts for a year or two with eruptions of the magnitude of Vesuvius."
When the epic gladiator battles and love story give way to the Plinian eruption at the end of "Pompeii," the movie, for the most part, accurately shows the events that followed, including the large tidal waves that washed into city streets, said Lopes, who attended an advance screening.
"There was definitely artistic license in making that wave really big," Lopes said. "Nevertheless, a little artistic license and exaggeration is OK because it's not a documentary, it's a drama."