The
plane parallel assumption
allows several simplifications:
no refraction,
no field-of-view effects, analytical Curtis-Godson path parameters.
The
SFC flag is required and, unless altered
by a separate
*SFC section, default values of
of surface temperature and emissivity are assumed.
It is also possible to define a nadir view with the full spherical
atmosphere calculations, replacing *TAN
section label with *ELE and setting an elevation angle −90.