Remote Sensing of Soil Properties:
Theoretically, the total upwelling radiance from an exposed soil recorded by the sensor,
Lt (Total upwelling radiance) as: Lt = Lp + Ls + Lv
Lp is the radiance recorded by a sensor resulting from the downwelling solar (Esun) and sky
(Esky) radiation. This is unwanted path radiance that never reaches the soil surface
Ls is the radiance that reaches the air-soil interface (boundary layer') and penetrates it
approximately 1/2 wavelength deep into the soils (microwave 1 cm-1m).
Lv is volume scattering. Some of the incident downwelling solar and sky radiation may be able
to penetrate perhaps millimeters or even a centimeter or two into the soils column.
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