Absorption data#

Absorption datasets tabulate the volume absorption coefficient of a gas mixture against spectral index, mixture’s components’ volume fraction, air pressure and air temperature.

For monochromatic absorption datasets, the spectral index consists of a radiation wavelength or radiation wavenumber coordinate.

For CKD absorption datasets, the spectral index consists of two coordinates:

  • the center of the spectral band (in wavelength or wavenumber space)

  • the absorption coefficient cumulative probability, or \(g\)-point.

Data access#

Distributed absorption datasets are available from the Eradiate store.

Note

You can also plug in your own datasets, provided they comply with the below specifications.

Specifications#

Monochromatic#

Monochromatic absorption coefficient datasets include one data variable:

  • volume absorption coefficient (sigma_a),

and at least four dimension coordinates:

  • radiation wavelength or radiation wavenumber (w),

  • gas mixture mole fractions (x_M where M is the molecule formula, e.g. x_H2O),

  • air pressure (p),

  • and air temperature (t).

CKD#

CKD absorption coefficient datasets include at least two data variables:

  • sigma_a [x_M, p, t, w, g] : volume absorption coefficient

  • wbounds [wbv, w] : band spectral bounds

one optional data variable:

  • error [w, ng] : relative error on atmosphere band-averaged transmittance,

at least five dimension coordinates:

  • w : radiation wavelength or radiation wavenumber of the band center,

  • wbv : band wavelength bounds,

  • g : quadrature \(g\)-point,

  • x_M (where M is the molecule formula, e.g. x_H2O, x_CO2): gas mixture mole fractions (1 to \(N_M\) coordinates where \(N_M\) is the number of molecules in the mixture),

  • p : air pressure,

  • t : and air temperature,

and, if the data variable error is present:

  • ng : number of quadrature \(g\)-point.

Available datasets#

Monochromatic datasets#

Available monochromatic datasets#

Codename

Spectral range

Sampling resolution

Online data store path

gecko

[250, 3125] nm

0.01 \(\rm{cm}^{-1}\) in [250, 300] \(\cup\) [600, 3125] nm, 0.1 \(\rm{cm}^{-1}\) in [300, 600] nm

spectra/absorption/mono/gecko/

komodo

[250, 3125] nm

1 \(\rm{cm}^{-1}\)

spectra/absorption/mono/komodo/

CKD datasets#

Available CKD datasets#

Codename

Spectral range

Band widths

Online data store path

monotropa

[250, 3125] nm

100 \(\rm{cm}^{-1}\)

spectra/absorption/ckd/monotropa/

panellus

[250, 3125] nm

1 nm

spectra/absorption/ckd/panellus/

mycena

[250, 3120] nm

10 nm

spectra/absorption/ckd/mycena/