Intensity scale for active fires



  • The intensity scale for the active fires map seems far too low. The Sydney fires are giving single figure W/m^2 intensities. Surely we should be talking kW or GW? Can anyone explain? Thanks.


  • Sailor

    @Farqhuit
    The fire intensity as shown by the Active fires map is not the thermal power of the fire itself but just its radiative thermal power measured by satellite.
    See:
    https://atmosphere.copernicus.eu/sites/default/files/2018-05/CAMS Global Fire Assimilation System (GFAS) data documentation.pdf
    and specially in Chapter 7 GFAS maps:
    ... The map represents the thermal radiation measured from space-borne sensors and detected as coming from actively burning vegetation and other open fires. It is expressed as the daily average of the fire radiative power (FRP) observations made in 125 km grid cells and expressed in the units of [mW/m2]. The rate of release of thermal radiation by fire is believed to be related to the rate at which fuel is being consumed and smoke produced. Therefore, these daily average FRP areal intensity data are used in the global estimation of open vegetation fire trace gas and particulate emissions...
    As the thermal radiation is expressed in mW/m2 (milliwatt per sq.m) it cannot be kW or GW per sq.m.

    The map below shows a consistent scale with the scale used by Windy.

    329EE150-7393-46AD-998A-D408E2DDD8AB.jpeg



  • @idefix37

    Ah! Thanks for clearing that up for me, makes sense now. What is plotted is basically the averaged raw data from the sensors.

    Cheers,

    Dave


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