====== Ice clouds - halo and crystal shape ======

Investigate the radiance field in presence of an ice cloud. What do you observe? What is the impact of the crystal shape?

An ice cloud can be defined in the libRadtran input file as follows:
<file bash ic.inp>
ic_properties hey interpolate
ic_habit solid-column
</file>
Please refer to the [[http://www.libradtran.org/doc/libradtran.pdf|libRadtran user manual]] to find out which crystal shapes are available. 
In order to use the HEY parameterization you have to copy the following data: 
  cp -r /home/data/daten/public/rt-data/optprop_data/ic/ /local/libRadtran-1.5-beta/data/

Use the libRadtran input file and the plotting script from [[teaching:radiative_transfer:disort_nstr1|exercise 6]] to start.

====== Solution by Sebastian and Hanna ======

===== Investigation of different particle shapes and cloud thicknesses =====

Cloud properties: [(height) (ice water content) (particle size)]

 thin cloud

  11 0 0  
  10 0.001 30

 thick cloud

  11 0 0
  10 0.006 70
  09 0.01 90
  08 0.004 50
  07 0 0

====Plots for different particle shapes at a solar zenith angle of 30° and a wavelength of 500 nm: ====
 
===thin cloud:===

[{{ :teaching:radiative_transfer:weak-solid-column-30wl500.png |Solid column.}}]
[{{ :teaching:radiative_transfer:weak-hollow-column-30wl500.png |Hollow column.}}]
[{{ :teaching:radiative_transfer:weak-rough-aggregate-30wl500.png |Rough aggregate.}}]
[{{ :teaching:radiative_transfer:weak-plate-30wl500.png |Plate.}}]
[{{ :teaching:radiative_transfer:weak-droxtal-30wl500.png |Droxtal}}]
  
===thick cloud:===

[{{ :teaching:radiative_transfer:solid-column-30wl500.png |Solid column.}}]
[{{ :teaching:radiative_transfer:hollow-column30wl500.png |Hollow column.}}]
[{{ :teaching:radiative_transfer:rough-aggregate30wl500.png |Rough aggregate.}}]
[{{ :teaching:radiative_transfer:plate30wl500.png |Plate.}}]
[{{ :teaching:radiative_transfer:droxtal30wl500.png |Droxtal}}]