==== Case D4: Aerosol layer (spheroid) ====

This case includes the same setup as case D1 but including spheroidal aerosol particles.

//Setup://

  * aerosol optical thickness: 0.2
  * aerosol optical properties: {{:intercomparisons:phase_a:sizedistr_spheroid.cdf|netCDF}},{{:intercomparisons:phase_a:sizedistr_spheroid.dat|ascii}} \\ The variable "phase" includes the phase matrix, as a function of the scattering angle (variable "theta"). The 4x4 scattering phase matrix for spherical droplets has four non-zero elements, which are stored in the following order: $ P = \begin{pmatrix} P1 &  P2 &  0 & 0 \\ P2 & P5 & 0 & 0 \\ 0 & 0 & P3 & P4 \\ 0 & 0 & -P4 & P6 \end{pmatrix} $ \\ The corresponding Legendre polynomials ("pmom") and the single scattering albedo ("ssa") are also included in the file.
  {{ :intercomparisons:phase_a:spheroids.png?900 |}}
The expansion moments over generalized spherical functions for the phase matrix have been provided by S. Korkin and are available {{:intercomparisons:phase_a:XK_A4.txt|here.}}

  * Earth radius: 6371 km
  * Thickness of layer: 100 km

  * D4_1: Twilight radiance field (normalized to incident irradiance) at the bottom of the layer:
    * sun position: //sza//:92°, //saa//:65°
    * viewing zenith angles: //vza//: 0° - 90°, 5° increment (up-looking)
    * viewing azimuth angles: //vaa//: 0° - 360°, 5° increment	     

  * D4_2: Limb radiance at top of atmosphere for 20 km tangent height
    * viewing zenith angle at TOA: //vza//: 81.9°
    * viewing azimuth angle at TOA: //vaa//: 30°
    * solar zenith angles: //sza//: 0° - 90°, 5° increment 
    * solar azimuth angles: //saa//: 0° - 360°, 5° increment	     
  

//Output format://

Please include your data in the netcdf file {{:intercomparisons:phase_d:iprt_phase3_model.nc|IPRT_phase3_MODELNAME.nc}}.