With Active Fire detection, the Fire Radiative Power (FRP) is one of the two Essential Climate Variables (ECV) related to ‘Fire Disturbance’ datasets highlighted by The United Nations Framework Convention on Climate Change (UNFCC).

It can be defined as the rate at which the actively burning fire is emitting radiative energy [at the time of observation] expressed in units of power (Js-1 or Watts). This radiative emission is primarily in the infrared, though fires emit visible light as well (seen for example as their luminous “flames”).  Through a series of airborne, ground-based and satellite data intercomparisons, FRP has been shown to be well related to the rate of fuel consumption, smoke aerosol production, and trace gas release, and thus offers a direct route for quantifying the magnitude of these processes.

This is effectively a direct result of the combustion process, whereby carbon-based fuel is oxidized to CO2 (and other compounds) with the release of a certain "heat yield". Therefore, measuring this FRP and integrating it over the lifetime of the fire provides an estimate of the total Fire Radiative Energy (FRE), which for wildfires should be approximately proportional to the total mass of fuel biomass consumed.