The California Canyon Fire Experiment - Initial Results

The California Canyon Fire Experiment was conducted as part of a prescribed fire program
on 24 October 2022. The project goal was to observe and measure fire spread in a steep canyon
to better understand extreme fire behavior in complex terrain. Fire behavior in canyons is often
associated with fire eruption or blow-up leading to extremely dangerous conditions and often
associated with firefighter fatalities and accidents. A number of instrument platforms and sensors
were used to sample the meteorology and fire behavior including 3-D sonic anemometers
installed on utility poles, two remote automated weather stations, a mobile scanning Ka-band
polarimetric Doppler radar, a sodar, Doppler wind lidar, various in situ fire behavior packages,
and two airborne infrared imaging systems. The SJSU Wildfire Imaging System (SWIS) was
mounted on a helicopter that hovered over the experiment at 300 m AGL and a longwave IR
video camera was mounted on a DJI M200 drone and flew 30 m above the fire front. The
experimental design was aimed at allowing a high-intensity head fire to spread through the
canyon which was approximately 100 acres in size and over 1 km in length. The ambient wind
conditions were weak (~ 3-4 m/s) allowing the fire behavior to be mainly driven by the terrain.
Fire eruption occurred approximately 1 hour after ignition and fire spread rates were observed to
increase as the fire front progressed up the canyon. To our knowledge, these comprehensive
observations represent the first of fire eruption in nature. This presentation will describe the
experimental design and preliminary results with a focus on the fire-induced winds that were
observed during the fire eruption.