==== Case B3: Aerosol profile  ====	

This test case includes a standard atmosphere with Rayleigh scattering and molecular absorption (as case B2). Aerosol with a specified optical thickness profile is added. The aerosol optical properties are the same as in case A4 (spheroidal particles)

//Setup//:

  * model atmosphere with 30 layers, scattering optical thicknesses provided in {{:intercomparisons:phase_b:tau_rayleigh_350.dat|}}, absorption optical thickness in {{:intercomparisons:phase_b:tau_molabs_350.dat|}} 
  * wavelength: 350 nm 
  * Rayleigh depolarization factor: 0.03
  * surface albedo: 0  

  * aerosol optical thickness profile: {{:intercomparisons:phase_b:tau_aerosol.dat|}}
  * 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 spheroidal droplets has six 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.

  * output altitudes: 0 km, 1 km, 30 km
  * sun position  (//sza//=30°, //saa//=0°)
  * viewing zenith angles: 
    * at 0 km : //vza//: 0° - 85°, 5° increment
    * at 1 km: //vza//: 0° - 180°, 5° increment (without 90°)
    * at 30 km: //vza//: 95° - 180°, 5° increment 
  * viewing azimuth angle //vaa//: 0° - 180°, 5° increment	     

//Output format://
  * The output should be provided in the same format as for case A1 ([[intercomparisons:a1_rayleigh|Rayleigh scattering]]).

 
=== Results ===

//Difference plots// between the models IPOL, 3DMCPOL, SPARTA (previously named TROPOS), SHDOM, PSTAR and MYSTIC for the full radiation field:\\
{{:intercomparisons:phase_b:b3:diff_b3_3dmcpol.pdf|3DMCPOL}}\\
{{:intercomparisons:phase_b:b3:diff_b3_ipol.pdf|IPOL}}\\
{{:intercomparisons:phase_b:b3:diff_b3_tropos.pdf|SPARTA}}\\
{{:intercomparisons:phase_b:b3:diff_b3_shdom3.pdf|SHDOM}}\\
{{:intercomparisons:phase_b:b3:diff_b3_pstar.pdf|PSTAR}}\\

//Data// of all models (MYSTIC and 3DMCPOL include also standard deviation):\\
{{:intercomparisons:phase_b:b3:iprt_case_b3_mystic.dat|MYSTIC}}\\	 
{{:intercomparisons:phase_b:b3:iprt_case_b3_3dmcpol.dat|3DMCPOL}}\\
{{:intercomparisons:phase_b:b3:iprt_case_b3_ipol.dat|IPOL}}\\
{{:intercomparisons:phase_b:b3:iprt_case_b3_tropos.dat|SPARTA}}\\
{{:intercomparisons:phase_b:b3:iprt_case_b3_shdom3.dat|SHDOM}}\\
{{:intercomparisons:phase_b:b3:iprt_case_b3_pstar.dat|PSTAR}}\\