Global Warming and Trapped Methane in the Melting Arctic

Evidence of global warming is most dramatic in the polar regions, where melting permafrost threatens polar bears and emperor penguins with extinction. Near the Arctic Circle, researchers are finding evidence of a different kind, huge pockets of methane, a major contributor to global warming 11,000 years ago with 20 times the heat-trapping effect of carbon dioxide. That's according to a report in the Los Angeles Times. The writer, Margot Roosevelt, explains out what that could mean.