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Workspace Method iyClearsky

Description

Standard method for radiative transfer calculations with emission
and a direct (solar, star) source
.
Designed to be part of iy_main_agenda. That is, only valid
outside the cloudbox (no scattering). For details se the user guide.

The possible choices for iy_unit are
 "1"             : No conversion, i.e. [W/(m^2 Hz sr)] (radiance per
                     frequency unit).
 "RJBT"          : Conversion to Rayleigh-Jean brightness
                     temperature.
 "PlanckBT"      : Conversion to Planck brightness temperature.
 "W/(m^2 m sr)"  : Conversion to [W/(m^2 m sr)] (radiance per
                     wavelength unit).
 "W/(m^2 m-1 sr)": Conversion to [W/(m^2 m-1 sr)] (radiance per
                     wavenumber unit).
Expressions applied and considerations for the unit conversion of
radiances are discussed in Sec. 5.7 of the ARTS-2.0 article.

iy_unit is only applied if iy_agenda_call1 is 1. This means that
no unit ocnversion is applied for internal iterative calls.

Recognised choices for rt_integration_option are:
   "first order": A first order integration is applied.
   "second order": A second order integration is applied.
   "default": Another way to select the first order option.

Some auxiliary radiative transfer quantities can be obtained. Auxiliary
quantities are selected by iy_aux_vars and returned by iy_aux.
Valid choices for auxiliary data are:
 "Radiative background": Index value flagging the radiative
    background. The following coding is used: 0=space, 1=surface
    and 2=cloudbox.
 "Optical depth": Scalar optical depth between the observation point
    and the end of the present propagation path. Calculated based on
    the (1,1)-element of the transmittance matrix (1-based indexing),
    i.e. only fully valid for scalar RT.
 "Direct radiation": Stokes vector of direct radiation. It dimensions
   are number of frequencies and stokes_dim. If no star is present 
   in the line of sight, it is zero.
 "Radiation Background": Stokes vector of the radiation at start of
   the propagation path. It dimensions are number of frequencies and
   stokes_dim.
If nothing else is stated, only the first column of iy_aux is filled,
i.e. the column matching Stokes element I, while remaing columns are
are filled with zeros.

IMPORTANT: No jacobian calculation is supported when stars or gas scattering is included! This will be implemented in a future version.

Authors: Patrick Eriksson, Richard Larsson, Oliver Lemke, Manfred Brath

Synopsis

iyClearsky( iy, iy_aux, diy_dx, ppvar_p, ppvar_t, ppvar_nlte, ppvar_vmr, ppvar_wind, ppvar_mag, ppvar_f, ppvar_iy, ppvar_trans_cumulat, ppvar_trans_partial, iy_id, stokes_dim, f_grid, atmosphere_dim, p_grid, lat_grid, lon_grid, z_field, t_field, nlte_field, vmr_field, abs_species, wind_u_field, wind_v_field, wind_w_field, mag_u_field, mag_v_field, mag_w_field, z_surface, refellipsoid, ppath_lmax, ppath_lraytrace, cloudbox_on, gas_scattering_do, stars_do, iy_unit, iy_aux_vars, jacobian_do, jacobian_quantities, ppath, rte_pos2, stars, propmat_clearsky_agenda, water_p_eq_agenda, rt_integration_option, iy_main_agenda, iy_space_agenda, iy_surface_agenda, iy_cloudbox_agenda, gas_scattering_agenda, ppath_step_agenda, iy_agenda_call1, iy_transmittance, rte_alonglos_v, surface_props_data )

Variables

OUTiy(Matrix)Monochromatic pencil beam radiance spectrum.
OUTiy_aux(ArrayOfMatrix)Data auxiliary to iy.
OUT+INdiy_dx(ArrayOfTensor3)Derivative of iy with respect to retrieval quantities.
OUTppvar_p(Vector)Pressure along the propagation path.
OUTppvar_t(Vector)Temperature along the propagation path.
OUTppvar_nlte(EnergyLevelMap)Non-LTE temperatures/ratios along the propagation path.
OUTppvar_vmr(Matrix)VMR values along the propagation path.
OUTppvar_wind(Matrix)Winds along the propagation path.
OUTppvar_mag(Matrix)Magnetic field along the propagation path.
OUTppvar_f(Matrix)Doppler adjusted frequencies along the propagation path.
OUTppvar_iy(Tensor3)iy-values along the propagation path.
OUTppvar_trans_cumulat(Tensor4)The transmittance between the sensor and each point of the propagation path.
OUTppvar_trans_partial(Tensor4)The transmittance between the points along the propagation path.
INiy_id(Index)Identification number of iy.
INstokes_dim(Index)The dimensionality of the Stokes vector (1-4).
INf_grid(Vector)The frequency grid for monochromatic pencil beam calculations.
INatmosphere_dim(Index)The atmospheric dimensionality (1-3).
INp_grid(Vector)The pressure grid.
INlat_grid(Vector)The latitude grid.
INlon_grid(Vector)The longitude grid.
INz_field(Tensor3)The field of geometrical altitudes.
INt_field(Tensor3)The field of atmospheric temperatures.
INnlte_field(EnergyLevelMap)The field of NLTE temperatures and/or ratios.
INvmr_field(Tensor4)VMR field.
INabs_species(ArrayOfArrayOfSpeciesTag)Tag groups for gas absorption.
INwind_u_field(Tensor3)Zonal component of the wind field.
INwind_v_field(Tensor3)Meridional component of the magnetic field.
INwind_w_field(Tensor3)Vertical wind component field.
INmag_u_field(Tensor3)Zonal component of the magnetic field.
INmag_v_field(Tensor3)Meridional component of the magnetic field.
INmag_w_field(Tensor3)Vertical component of the magnetic field.
INz_surface(Matrix)The surface altitude.
INrefellipsoid(Vector)Reference ellipsoid.
INppath_lmax(Numeric)Maximum length between points describing propagation paths.
INppath_lraytrace(Numeric)Maximum length of ray tracing steps when determining propagation paths.
INcloudbox_on(Index)Flag to activate the cloud box.
INgas_scattering_do(Index)Flag to activate gas scattering.
INstars_do(Index)Flag to activate the star(s).
INiy_unit(String)Selection of output unit for radiative transfer methods.
INiy_aux_vars(ArrayOfString)Selection of quantities for iy_aux and when applicable also y_aux.
INjacobian_do(Index)Flag to activate (clear-sky) Jacobian calculations.
INjacobian_quantities(ArrayOfRetrievalQuantity)The retrieval quantities in the Jacobian matrix.
INppath(Ppath)The propagation path for one line-of-sight.
INrte_pos2(Vector)A second geographical position to define the geometry for radiative transfer calculations.
INstars(ArrayOfStar)Array of Star.
INpropmat_clearsky_agenda(Agenda)Agenda calculating the absorption coefficient matrices.
INwater_p_eq_agenda(Agenda)Agenda to calculate the saturation pressure of water.
INrt_integration_option(String)Switch between integration approaches for radiative transfer steps.
INiy_main_agenda(Agenda)Agenda calculating the single monochromatic pencil beam spectrum.
INiy_space_agenda(Agenda)Agenda providing the downwelling radiation at the top of the atmosphere.
INiy_surface_agenda(Agenda)Agenda providing the upwelling radiation from the surface.
INiy_cloudbox_agenda(Agenda)Agenda deriving the intensity at boundary or interior of the cloudbox.
INgas_scattering_agenda(Agenda)Agenda calculating gas scattering extinction and phase matrix.
INppath_step_agenda(Agenda)Agenda calculating a propagation path step.
INiy_agenda_call1(Index)Flag to handle recursive calls of iy_main_agenda The agenda iy_main_agenda can be used recursively and this flag is used to tell the methods inside the agenda which is the primary call.
INiy_transmittance(Tensor3)Transmittance to be included in iy.
INrte_alonglos_v(Numeric)Velocity along the line-of-sight to consider for a RT calculation.
INsurface_props_data(Tensor3)Various surface properties.