colour.rayleigh_scattering#

colour.rayleigh_scattering(wavelength: FloatingOrArrayLike, CO2_concentration: FloatingOrArrayLike = CONSTANT_STANDARD_CO2_CONCENTRATION, temperature: FloatingOrArrayLike = CONSTANT_STANDARD_AIR_TEMPERATURE, pressure: FloatingOrArrayLike = CONSTANT_AVERAGE_PRESSURE_MEAN_SEA_LEVEL, latitude: FloatingOrArrayLike = CONSTANT_DEFAULT_LATITUDE, altitude: FloatingOrArrayLike = CONSTANT_DEFAULT_ALTITUDE, avogadro_constant: FloatingOrArrayLike = CONSTANT_AVOGADRO, n_s_function: Callable = air_refraction_index_Bodhaine1999, F_air_function: Callable = F_air_Bodhaine1999) FloatingOrNDArray#

Return the Rayleigh optical depth \(T_r(\lambda)\) as function of wavelength \(\lambda\) in centimeters (cm).

Parameters
  • wavelength (FloatingOrArrayLike) – Wavelength \(\lambda\) in centimeters (cm).

  • CO2_concentration (FloatingOrArrayLike) – \(CO_2\) concentration in parts per million (ppm).

  • temperature (FloatingOrArrayLike) – Air temperature \(T[K]\) in kelvin degrees.

  • pressure (FloatingOrArrayLike) – Surface pressure \(P\) of the measurement site.

  • latitude (FloatingOrArrayLike) – Latitude of the site in degrees.

  • altitude (FloatingOrArrayLike) – Altitude of the site in meters.

  • avogadro_constant (FloatingOrArrayLike) – Avogadro’s number (molecules \(mol^{-1}\)).

  • n_s_function (Callable) – Air refraction index \(n_s\) computation method.

  • F_air_function (Callable) – \((6+3_p)/(6-7_p)\), the depolarisation term \(F(air)\) or King Factor computation method.

Returns

Rayleigh optical depth \(T_r(\lambda)\).

Return type

numpy.floating or numpy.ndarray

Warning

Unlike most objects of colour.phenomena.rayleigh module, colour.phenomena.rayleigh_optical_depth() expects wavelength \(\lambda\) to be expressed in centimeters (cm).

References

[BWDS99], [Wikipedia01d]

Examples

>>> rayleigh_optical_depth(555 * 10e-8)  
0.1004070...