Paleontologist Peter Ward, professor of biology at the University of Washington and an expert on mass extinction events, stopped by Big Think today to discuss nothing less than the fate of the planet. How is it looking? Not too rosy, says Ward, who has just returned from measuring CO2 levels in Antarctica.

Ward's interview will be posted as part of our upcoming series on plausible doomsday scenarios, called "How the World Might Really End." He offered not one but many juicy scenarios to choose from: greenhouse-induced flooding and sulphur poisoning, an asteroid impact, the eventual freezing of the planet's core...

Ward's newest book, "The Medea Hypothesis" (which posits that we're not the only self-destructive species on Earth), is due out in March.