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optical thickness, <of the atmosphere>

optical depth, <of the atmosphere>


where Φe is the radiant flux of a collimated beam entering the upper limit layers of the atmosphere at an angle ε to the vertical, and is the attenuated radiant flux of that beam reaching the surface of the Earth

Note 1 to entry: See also "spectral optical thickness".

Note 2 to entry: The optical thickness has unit one.

Note 3 to entry: This entry was numbered 845-09-86 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-850 and 17-844 in CIE S 017:2011.

Publication date: 2020-12
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