We often think of destructive wildfires in terms of their size and the damage they cause: the number of acres burned or buildings destroyed.  But emerging research says not all major wildfires belong in the same category.   Some wildfires ignite and spread explosively. They move so swiftly that firefighting crews simply can’t keep up. The 2021 Marshall Fire, which scorched about a thousand homes in Boulder County, is one recent example of what experts call a “fast fire.” And this more destructive type of wildfire is becoming more common in a hotter, drier and more densely populated American West. Virginia Iglesias is an environmental scientist and director of Earth Lab at the University of Colorado Boulder. She studies fast fires. She joined Erin O'Toole to talk about what makes fast fires especially dangerous – and how we might respond differently to them. * * * * *Sign up for the In The NoCo newsletter: Visit KUNC.org Questions? Feedback? Story ideas? Email us: [email protected] Like what you're hearing? Help more people discover In The NoCo by rating the show on your favorite podcast app. Thanks!  Host and Producer: Erin O'Toole Executive Producer: Brad Turner  Theme music by Robbie Reverb Additional music by Blue Dot Sessions In The NoCo is a production of KUNC News and Community Radio for Northern Colorado.