No, it's not the zombies that are burning (they're still after you)

A Zombie-Fire Outbreak May Be Growing in the North

Beneath all that white serenity, some of those fires actually continue smoldering underground, chewing through carbon-rich peat, biding their time. When spring arrives and the chilly landscape defrosts, these “overwintering” fires pop up from below—that’s why scientists call them zombie fires.