VRT Flag

RFM Flags: Suppress solid-angle integration in Flux calculations

01MAR25
Enabled

Disabled

Restrictions
FLX Flag must be enabled
Incompatible with COO Flag.

Notes
  1. The main purpose of this flag is to allow multiple vertical path calculations to different atmosphere levels within the same driver table instead of using different driver tables with the OBS Flag used to set the observer altitude at each level. However, for most purposes, the LEV Flag is simpler to use and more flexible.

  2. Using the VRT Flag to calculate, for example, the (vertical) radiance from the top of the atmosphere down to 25km one could either use
    *FLG ZEN RAD OBS ! observer looking upwards at downwelling radiance ... *SEC (or *TAN) 1.0 ! defines vertical path ... *OBS 25.0 ! observer at 25km ... *END
    or one could get the same answer using
    *FLG ZEN RAD FLX VRT ! flux-type calc without solid-angle ... *HGT (or *TAN) 25.0 ! output at 25km ... *END
    The difference is that further entries in the *SEC section in the first example create additional spectra corresponding to different viewing angles, while in the second example extra entries in the *HGT section create downwelling spectra to different altitudes.

Bugs
[none recent]