2.4: Surfaces - Single-scattering Albedo

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Page ID: 7499

Max Fairbairn & Jeremy Tatum
University of Victoria

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We have already encountered a bare-boned, but nonetheless adequate, definition of single scattering albedo in Chapter 1. The loss of radiance from a beam of radiance \(L\) traversing a thickness \(ds\) of a medium is

\[ dL = - \varepsilon L ds = - ( \alpha + \sigma ) L ds\]

and the single scattering albedo is that fraction of the loss which can be attributed to scattering alone. i.e.

\[ \varpi_0 = \frac{ \sigma}{ \alpha + \sigma} = \frac{ \sigma}{ \varepsilon}\]

and the single scattering albedo is thus the ratio of the scattering coefficient to the extinction coefficient.

Single scattering albedo is the property of a surface or a layer, and may be regarded as the fundamental albedo, since all albedos that will be derived here from a given definition or reflectance rule will contain at least one instance of ϖ₀.