How 'zombie fires' stay alive underground

Many will remember the apocalyptic skies on the East Coast last summer — day turned to night in Manhattan as smoke from Canadian wildfires blanketed massive swaths of the country from New York to Florida. Emergency preparedness officials in Canada say this year's wildfire season could be worse.

Part of the problem could be so-called 'zombie fires,' which are buried but refusing to die.

Mike Flannigan is a professor of Wildfire Science at Thompson Rivers University in British Columbia, where nearly 100 of these fires are burning. He joins host Robin Young to talk about these fires and the season ahead.