===== Model intercomparison, Thermal IR spectral region =====


=== Line-by-line calculations with provided absorption coefficients ===

  * viewing geometry: top of atmosphere, nadir
  * surface emissivities 1.0, 0.8, 0.5, assuming a Lambertian surface.
  * output quantity: radiance [W/(m^2 cm-1 sr)]

== 1. Water vapor band, ~6.2 μm, nadir ==

{{:studies:esaslight2:thermal_ir:moltau_6.2.nc|Absorption optical thickness table}}

== 2. Spectral window, ~10.8 μm, nadir ==

{{:studies:esaslight2:thermal_ir:moltau_10.8.nc|Absorption optical thickness table}}

== 3. Spectral window, ~10.0 μm, nadir ==

{{:studies:esaslight2:thermal_ir:moltau_10.0.nc|Absorption optical thickness table}}

== Benchmark results ==

{{:studies:esaslight2:thermal_ir:disort_spectra.nc|DISORT}}\\
{{:studies:esaslight2:thermal_ir:arts_spectra.nc|ARTS}}

=== Monochromatic calculations for different viewing angles ===

  * Viewing zenith angles: 0°-95° in 1° steps
  * If possible, spherical geometry, earth radius 6370 km
  * wavelengths: 6190 nm, 10795 nm
  * absorption optical thicknesses from LBL calculations above

== Benchmark results ==

{{:studies:esaslight2:thermal_ir:angular_dep_arts.dat|ARTS}}\\
{{:studies:esaslight2:thermal_ir:angular_dep_disort.dat|DISORT}}

All KOPRA results (spectra for all combinations of angles and emissivities) are provided in the following files, radiance unit is [nW/(cm^2 cm-1 sr)]:

{{:studies:esaslight2:thermal_ir:spec_6.2emi1.0reflngeo19nlay190_nlay190_ckd_.nc|6.2 nm, emi 1.0}}
{{:studies:esaslight2:thermal_ir:spec_6.2emi0.8reflngeo19nlay190_nlay190_ckd_.nc|6.2 nm, emi 0.8}}
{{:studies:esaslight2:thermal_ir:spec_6.2emi0.5reflngeo19nlay190_nlay190_ckd_.nc|6.2 nm, emi 0.5}}

{{:studies:esaslight2:thermal_ir:spec_10.0emi1.0reflngeo19nlay190_nlay190_ckd_.nc|10.0 nm, emi 1.0}}
{{:studies:esaslight2:thermal_ir:spec_10.0emi0.8reflngeo19nlay190_nlay190_ckd_.nc|10.0 nm, emi 0.8}}
{{:studies:esaslight2:thermal_ir:spec_10.0emi0.5reflngeo19nlay190_nlay190_ckd_.nc|10.0 nm, emi 0.5}}

{{:studies:esaslight2:thermal_ir:spec_10.8emi1.0reflngeo19nlay190_nlay190_ckd_.nc|10.8 nm, emi 1.0}}
{{:studies:esaslight2:thermal_ir:spec_10.8emi0.8reflngeo19nlay190_nlay190_ckd_.nc|10.8 nm, emi 0.8}}
{{:studies:esaslight2:thermal_ir:spec_10.8emi0.5reflngeo19nlay190_nlay190_ckd_.nc|10.8 nm, emi 0.5}}

=== General information ===

  * The absorption coefficients have been generated using ARTS based on HITRAN 2004
  * Midlatitude summer atmosphere was used
  * Participating RT Solvers: DISORT, ARTS, KOPRA