On June 6, 2010 lightning ignited the Medano Fire in Great Sand Dunes National Park in Colorado. This image shows thick smoke billowing over the sand dunes. By the time this image was taken on June 23 more than 5000 acres had burned. Firefighters used a containment strategy in order to reduce risk for firefighters. NCAR scientists are studying wildfires in order to forecast fire-weather interactions, assess emissions, and understand the social impacts.