Fire Radiative Power Turns a Hot Pixel Into an Energy Rate
A fire detection tells you where; fire radiative power tells you how hard it is burning. Because emitted radiance in the midwave infrared rises very steeply with temperature, the excess midwave radiance of a fire pixel over its background can be converted into the radiative power the fire is releasing within that pixel, reported in megawatts. Satellite products such as those from MODIS and VIIRS carry a fire radiative power value alongside every detection, and the useful properties follow directly. It is roughly proportional to the rate at which fuel is being consumed, so it is the standard remote proxy for fire intensity and, integrated over time, for total fuel burned and smoke emitted. It is a per-pixel figure, so it depends on what fraction of the pixel is burning and is systematically underestimated for pixels viewed far off-nadir or partly obscured by thick smoke or cloud. It is a radiative quantity, capturing only the fraction of released energy that leaves as radiation. After this Concept you can compare two fire detections by intensity rather than by dot count, and state when that comparison is unfair.
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A fire detection tells you where; fire radiative power tells you how hard it is burning. Because emitted radiance in the midwave infrared rises very steeply with temperature, the excess midwave radiance of a fire pixel over its background can be converted into the radiative power the fire is releasing within that pixel, reported in megawatts. Satellite products such as those from MODIS and VIIRS carry a fire radiative power value alongside every detection, and the useful properties follow directly. It is roughly proportional to the rate at which fuel is being consumed, so it is the standard remote proxy for fire intensity and, integrated over time, for total fuel burned and smoke emitted. It is a per-pixel figure, so it depends on what fraction of the pixel is burning and is systematically underestimated for pixels viewed far off-nadir or partly obscured by thick smoke or cloud. It is a radiative quantity, capturing only the fraction of released energy that leaves as radiation. After this Concept you can compare two fire detections by intensity rather than by dot count, and state when that comparison is unfair.
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