Fourth Symposium on Fire and Forest Meteorology

Tuesday, 13 November 2001: 11:30 AM
Airborne infrared observations of wildfire, dynamics, and spread
Lawrence F. Radke, NCAR, Boulder, CO; and T. L. Clark and R. B. Stull
Wildfire suppression presents an array of practical challenges to its practitioners. Amongst the most critical decision making tasks is to: · Assess risk to firefighters. · Estimate fire spread rates. · Forecast major transitions in fire behavior. · Observe and warn of the onset of extreme fire activity.

Real-time airborne infrared remote sensing holds promise to carry out these four tasks in near real-time using comparatively low-cost tools aboard various general aviation aircraft.

The recently available mechanically cryogenically cooled digital IR array imagers are proving their utility in airborne observations of wildfire dynamics to temporal scales as small as .02 s. Their images can be coupled with advanced data processing software that first removes extraneous aircraft roll, yaw, and pitch motions and then discern motions within the wildfire as it interacts with the atmosphere, wildland fuels, and terrain.

These motions can be digitally processed to discern local fire driven vertical winds that are critical to airborne fire suppression management. We observe near surface, fire induced winds of 40 - 50ms -1, which is sufficient to dangerously upset many aircraft types at low altitude.

This technology is also applied to fast-moving extreme event crown fires to extend fire spread vectors which are urgently needed by wildfire managers to assess fire threat, allocate suppression resources, and limit personal hazards. Examples of observations of wildfire from aircraft will be presented with both high temporal and spatial resolution together with advanced digital processing.

Supplementary URL: