EAGER: Observing Extreme Fire Behavior in Canyons

San Jose State University Foundation, San Jose CA

Investigators

Abstract

Fire behavior in canyons is often associated with explosive rates of spread responsible for many firefighter fatalities around the world. Yet, the dominant physical processes responsible for explosive fire growth in canyons remain poorly understood and rarely observed. This project seeks to improve understanding of canyon fire behavior and associated fire weather by conducting a field-scale experiment to collect a suite of new observations of a fire spreading through a steep canyon. This new dataset will help to identify the critical processes leading to the fire acceleration in steep canyons and will serve as an international benchmark for fire prediction model development and provide data that do not currently exist. In the broader scope, the results from this EAGER project will lead to improved fire risk assessment, increased firefighter safety, and better management decisions in mountain regions particularly as wildfires are becoming increasingly more frequent and destructive due to climate change. Using a suite of measurements never previously available, this EAGER project will observe the complete fire evolution from both airborne and ground based remote sensing systems. Convection and radiative heat transfer mechanisms sensitive to canyon topography and resulting fire-atmosphere interactions including fire-induced winds and turbulence structures will be sampled together with the fire dynamics. Furthermore, plume dynamics and associated micrometeorology near the fire front will provide additional context of the interactions between the pyroconvection and fire environment. These novel observations will serve as a foundation to explore many questions including how fire-induced updrafts drive fire spread and how wind alignment with the canyon axis increases convective heating of the fuels and accelerates the rate of spread. The measurement campaign will be supported by numerical simulations made using a coupled fire-atmosphere forecasting system and together will serve as a complete dataset providing an unprecedented examination of the physics governing fire spread in canyon topography. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.