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Workspace Method propmat_clearskyAddParticles

Description

Calculates absorption coefficients of particles to be used in
clearsky (non-cloudbox) calculations.

This is a method to include particles (neglecting possible
scattering components) in a clearsky calculation, i.e. without
applying the cloudbox and scattering solvers. Particles are handled
as absorbing species with one instance of 'particles' per scattering
element considered added to abs_species. Particle absorption cross-
sections at current atmospheric conditions are extracted from the
single scattering data stored in scat_data, i.e., one array
element per 'particles' instance in abs_species is required. Number
densities are stored in vmr_field_raw or vmr_field as for all
abs_species, but can be taken from (raw) pnd_field type data.

Note that the absorption coefficient is applied both in the
extinction term (neglecting scattering out of the line of sight)
and the emission term (neglecting the scattering source term, i.e.
scattering into the line of sight).

Optionally, particle extinction (sum of absorption and scattering
coefficient) can be used instead of absorption only. To choose this
case, set the *use_abs_as_ext* flag to 0. However, be aware that
this creates some unphysical emission term, hence is only suitable,
where the source term is negligible anyways, e.g. for occultation
simulations.

A line-of-sight direction rtp_los is required as particles can
exhibit directional dependent absorption properties, which is taken
into account by this method.
ScatElementsToabs_speciesAdd can be used to add all required
settings/data for individual scattering elements at once, i.e. a
 'particles' tag to abs_species, a set of single scattering data to
scat_data and a number density field to vmr_field_raw
(vmr_field is derived applying AtmFieldsCalc once VMRs for all
abs_species have been added) is appended for each scattering
element.

Like all 'propmat_clearskyAdd*' methods, the method is additive,
i.e., does not overwrite the propagation matrix propmat_clearsky,
but adds further contributions.

Authors: Jana Mendrok

Synopsis

propmat_clearskyAddParticles(

propmat_clearsky, dpropmat_clearsky_dx, stokes_dim, atmosphere_dim, f_grid, abs_species, jacobian_quantities, rtp_vmr, rtp_los, rtp_temperature, scat_data, scat_data_checked, use_abs_as_ext )

Variables

OUT+IN	propmat_clearsky	(ArrayOfPropagationMatrix)	This contains the absorption coefficients for one point in the atmosphere (one set of pressure, temperature, magnetic field, and VMR values).
OUT+IN	dpropmat_clearsky_dx	(ArrayOfPropagationMatrix)	Partial derivative of absorption coefficients.
IN	stokes_dim	(Index)	The dimensionality of the Stokes vector (1-4).
IN	atmosphere_dim	(Index)	The atmospheric dimensionality (1-3).
IN	f_grid	(Vector)	The frequency grid for monochromatic pencil beam calculations.
IN	abs_species	(ArrayOfArrayOfSpeciesTag)	Tag groups for gas absorption.
IN	jacobian_quantities	(ArrayOfRetrievalQuantity)	The retrieval quantities in the Jacobian matrix.
IN	rtp_vmr	(Vector)	Absorption species abundances for radiative transfer calculations.
IN	rtp_los	(Vector)	Line-of-sight at a radiative transfer point.
IN	rtp_temperature	(Numeric)	Temperature at a radiative transfer point.
IN	scat_data	(ArrayOfArrayOfSingleScatteringData)	Array of single scattering data.
IN	scat_data_checked	(Index)	OK-flag for scat_data.
GIN	use_abs_as_ext	(Index, Default: 1)	A flag with value 1 or 0. If set to one, particle absorption is used in extinction and emission parts of the RT equation, and scattering out of LOS as well as into LOS is neglected. Otherwise, particle extinction (absorption+scattering) is applied in both the extinction as well as the emission part of the RT equation. That is, true extinction is applied, but emission also includes a pseudo-emission contribution from the scattering coefficient.