Analyses of fire growth and behavior using new VIIRS 375 m active fire data and a coupled weather-fire model (CAWFE)

Abstract:

Recent advances in satellite fire detection and mapping and coupled weather-wildland fire modeling present a new opportunity to routinely map fire extent and progression, examine active fire areas in greater detail, and predict fire growth, intensification, and extreme behaviors of wildfires lasting several days. The new Visible Infrared Imaging Radiometer Suite (VIIRS) aboard the NASA/NOAA Suomi-NPP satellite provides 12h global coverage at spatial resolutions of 375 m and 750 m. Compared to coarser resolution products, the new VIIRS 375 m active fire detection product enables early detection of small fires and improved mapping of large wildfires. NCAR’s Coupled Atmosphere-Wildland Fire Environment (CAWFE) combines a numerical weather prediction model with wildland fire behavior algorithms to simulate fire behavior. These not only predict a fire’s shape and extent, but extreme behaviors such as fire whirls, blow-ups, splitting of the head, flank runs, and pyrocumulus, all resulting from a fire’s interaction with its environment, i.e. how the fire creates its own weather. We use the new VIIRS 375 m fire data to initialize and evaluate the CAWFE model, enabling accurate simulation of complex fire behavior during long-lasting wildfires. Compared to traditional models, this approach can now be applied to monitor and predict the growth of a fire or a group of simultaneous wildfires in a management unit from first detection until containment – a previously unattainable goal due to accumulation of model error.