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variable > irradiance

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  • [ECSO]* Irradiance, radiant emittance, and radiant exitance are radiometry terms for the power per unit area of electromagnetic radiation at a surface. 'Irradiance' is used when the electromagnetic radiation is incident on the surface. 'Radiant exitance' or 'radiant emittance' is used when the radiation is emerging from the surface. The SI units for all of these quantities are watts per square meter (W/m2) (wikipedia). All of these quantities characterize the total amount of radiation present, at all frequencies. It is also common to consider each frequency in the spectrum separately. When this is done for radiation incident on a surface, it is called spectral irradiance, and has SI units W/m3. Irradiance is the radiant flux (power) received by a surface per unit area.

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  • Johannes

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  • US LTER controlled vocabulary




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