Landscape estimates of heat release from prescribed fires: analysis and calibration of infrared imagery from aircraft
We used infrared images acquired from aircraft and ground-based calibration to produce sequential maps of fire radiative power (FRP, kW m-2) over the period of active flaming during prescribed fires. Ground sensors were calibrated for total radiant heat flux. Because the residence time of flaming combustion is short relative to the aircraft return time (4-5 min), integrating FRP over time to estimate fire radiative energy (FRE, kJ m-2) is not straightforward. Integration can be done for pixels where active flaming fronts can be identified and if the typical time course of FRP can be estimated independently. Heat flux data from ground sensors within the fires and from experimental fires were used to describe the time course of heat release. Experimental data and the literature were used to estimate the proportionality between energy release and total and rate of fuel consumption. Image analysis showed considerable variability among prescribed fires in spatial pattern and magnitude of heat release owing to fire weather and ignition method.
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- 0480 Remote sensing