refr_index_airMicrowavesEarth

Workspace.refr_index_airMicrowavesEarth(self: pyarts.arts._Workspace, refr_index_air: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = self.refr_index_air, refr_index_air_group: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = self.refr_index_air_group, rtp_pressure: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = self.rtp_pressure, rtp_temperature: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = self.rtp_temperature, rtp_vmr: pyarts.arts.WorkspaceVariable | pyarts.arts.Vector | None = self.rtp_vmr, abs_species: pyarts.arts.WorkspaceVariable | pyarts.arts.ArrayOfArrayOfSpeciesTag | None = self.abs_species, k1: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = 77.6e-8, k2: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = 70.4e-8, k3: pyarts.arts.WorkspaceVariable | pyarts.arts.Numeric | None = 3.739e-3, verbosity: pyarts.arts.WorkspaceVariable | pyarts.arts.Verbosity | None = self.verbosity) None

Microwave refractive index in Earth’s atmosphere.

This method just considers pressure, temperature and water vapour, which should suffice for Earth. For a more general method, see refr_index_airMicrowavesGeneral().

The refractivity of dry air and water vapour is added to refr_index_air. To obtain the complete value, refr_index_air should be set to 1 before calling this WSM. This applies also to refr_index_air_group.

The expression used is non-dispersive. Hence, refr_index_air and refr_index_air_group are identical.

The standard expression for Earth and microwaves is used:

N = k1*(P-e)/T + k2*e/T + k3*e/T^2

where N is refractivity, P is pressure, T is temperature and e is water vapour partial pressure. The values of k1, k2 and k3 can be modified.

Many different values of k1, k2 and k3 can be found in the literature. The default values applied here are taken from Bevis et al., GPS meteorology: Mapping …, JAM, 1994. More specifically, these value are found in Table 1, listed as “Present study”. Note that in ARTS Pa is used for pressure and k1, k2 and k3 must be adjusted accordingly.

Author(s): Patrick Eriksson

Parameters:
  • refr_index_air (Numeric, optional) – Real part of the refractive index of air. See refr_index_air, defaults to self.refr_index_air [INOUT]

  • refr_index_air_group (Numeric, optional) – Group index of refractivity. See refr_index_air_group, defaults to self.refr_index_air_group [INOUT]

  • rtp_pressure (Numeric, optional) – Pressure at a radiative transfer point. See rtp_pressure, defaults to self.rtp_pressure [IN]

  • rtp_temperature (Numeric, optional) – Temperature at a radiative transfer point. See rtp_temperature, defaults to self.rtp_temperature [IN]

  • rtp_vmr (Vector, optional) – Absorption species abundances for radiative transfer calculations. See rtp_vmr, defaults to self.rtp_vmr [IN]

  • abs_species (ArrayOfArrayOfSpeciesTag, optional) – Tag groups for gas absorption. See abs_species, defaults to self.abs_species [IN]

  • k1 (Numeric, optional) – Coefficient a, see above. Defaults to 77.6e-8 [IN]

  • k2 (Numeric, optional) – Coefficient b, see above. Defaults to 70.4e-8 [IN]

  • k3 (Numeric, optional) – Coefficient c, see above. Defaults to 3.739e-3 [IN]

  • verbosity (Verbosity) – ARTS verbosity. See verbosity, defaults to self.verbosity [IN]