spectral_irradiance_fieldDisort

Interface to the DISORT scattering solver (by Stamnes et al.). for running flux (irradiance) calculations

It provides the irradiance field from a scalar 1D scattering solution assuming a plane-parallel atmosphere (flat Earth). Only totally randomly oriented particles are allowed. Refraction is not taken into account. Only Lambertian surface reflection is handled.

nstreams is the number of polar angles taken into account internally in the scattering solution and for the angular integration. nstreams determines the angular resolution, hence the accuracy, of the scattering solution. The more anisotropic the bulk scattering matrix, the more streams are required. The computational burden increases approximately linearly with nstreams. The default value (6) is sufficient for most flux calculations.

Some auxiliary quantities can be obtained. Auxiliary quantities are selected by disort_aux_vars and returned by disort_aux. Valid choices for auxiliary data are:

"Layer optical thickness": Matrix [f_grid, size of p_grid - 1] layer optical thickness.
"Single scattering albedo": Matrix [f_grid, size of p_grid - 1] layer single scattering albedo.
"Direct downward spectral irradiance": Matrix [f_grid, p_grid]. Direct downward spectral irradiance. Zero, if no sun is present.
"dFdtau": Matrix [f_grid, p_grid]. Flux divergence in optical thickness space.

Author(s): Manfred Brath

Parameters:

spectral_irradiance_field (Tensor5, optional) – Spectral irradiance field. See spectral_irradiance_field, defaults to self.spectral_irradiance_field [OUT]
disort_aux (ArrayOfMatrix, optional) – Auxilary data to the output of the cloudbox_fieldDisort-Methods. See disort_aux, defaults to self.disort_aux [OUT]
atmfields_checked (Index, optional) – OK-flag for atmospheric grids and (physical) fields. See atmfields_checked, defaults to self.atmfields_checked [IN]
atmgeom_checked (Index, optional) – OK-flag for the geometry of the model atmosphere. See atmgeom_checked, defaults to self.atmgeom_checked [IN]
scat_data_checked (Index, optional) – OK-flag for scat_data. See scat_data_checked, defaults to self.scat_data_checked [IN]
propmat_clearsky_agenda (Agenda, optional) – Calculate the absorption coefficient matrix. See propmat_clearsky_agenda, defaults to self.propmat_clearsky_agenda [IN]
gas_scattering_agenda (Agenda, optional) – Calculation of the gas scattering extinction and phase matrix. See gas_scattering_agenda, defaults to self.gas_scattering_agenda [IN]
atmosphere_dim (Index, optional) – The atmospheric dimensionality (1-3). See atmosphere_dim, defaults to self.atmosphere_dim [IN]
pnd_field (Tensor4, optional) – Particle number density field. See pnd_field, defaults to self.pnd_field [IN]
t_field (Tensor3, optional) – The field of atmospheric temperatures. See t_field, defaults to self.t_field [IN]
z_field (Tensor3, optional) – The field of geometrical altitudes. See z_field, defaults to self.z_field [IN]
vmr_field (Tensor4, optional) – VMR field. See vmr_field, defaults to self.vmr_field [IN]
p_grid (Vector, optional) – The pressure grid. See p_grid, defaults to self.p_grid [IN]
lat_true (Vector, optional) – Latitudinal geolocation for 1D and 2D data. See lat_true, defaults to self.lat_true [IN]
lon_true (Vector, optional) – Longitudinal geolocation for 1D and 2D data. See lon_true, defaults to self.lon_true [IN]
refellipsoid (Vector, optional) – Reference ellipsoid. See refellipsoid, defaults to self.refellipsoid [IN]
scat_data (ArrayOfArrayOfSingleScatteringData, optional) – Array of single scattering data. See scat_data, defaults to self.scat_data [IN]
suns (ArrayOfSun, optional) – Array of Sun. See suns, defaults to self.suns [IN]
f_grid (Vector, optional) – The frequency grid for monochromatic pencil beam calculations. See f_grid, defaults to self.f_grid [IN]
stokes_dim (Index, optional) – The dimensionality of the Stokes vector (1-4). See stokes_dim, defaults to self.stokes_dim [IN]
z_surface (Matrix, optional) – The surface altitude. See z_surface, defaults to self.z_surface [IN]
surface_skin_t (Numeric, optional) – Surface skin temperature. See surface_skin_t, defaults to self.surface_skin_t [IN]
surface_scalar_reflectivity (Vector, optional) – Surface reflectivity, assuming it can be described as a scalar value. See surface_scalar_reflectivity, defaults to self.surface_scalar_reflectivity [IN]
gas_scattering_do (Index, optional) – Flag to activate gas scattering. See gas_scattering_do, defaults to self.gas_scattering_do [IN]
suns_do (Index, optional) – Flag to activate the sun(s). See suns_do, defaults to self.suns_do [IN]
disort_aux_vars (ArrayOfString, optional) – Selection of quantities for disort_aux. See disort_aux_vars, defaults to self.disort_aux_vars [IN]
nstreams (Index, optional) – Number of polar angle directions (streams) in DISORT solution (must be an even number). Defaults to 6 [IN]
Npfct (Index, optional) – Number of angular grid points to calculate bulk phase function on (and derive Legendre polynomials from). If <0, the finest za_grid from scat_data will be used. Defaults to 181 [IN]
only_tro (Index, optional) – Set to 1 if the scattering data is just of TRO type. Has effect only if Npfct > 3 or Npfct<0, but then leads to much faster calculations. Defaults to 0 [IN]
quiet (Index, optional) – Silence C Disort warnings. Defaults to 0 [IN]
emission (Index, optional) – Enables blackbody emission. Set to zero, if no Emission e. g. like in visible regime for earth is needed. Defaults to 1 [IN]
intensity_correction (Index, optional) – Enables intensity correction. Importantant for low number of streams. Set to zero, if problems encounter or using a high number of streams (>30). Defaults to 1 [IN]
verbosity (Verbosity) – ARTS verbosity. See verbosity, defaults to self.verbosity [IN]