Retrieval

Base Class

class skdoas.retrieval.base.Retrieval

Class used to perform a complete DOAS-style retrieval, including the SCD spectral fitting and AMF correction.

OMI NO2 Standard Product V2.1 - Total Column

class skdoas.retrieval.omno2.Retrieval_OMNO2_TotalColumnOnly(slant_column: Optional[skdoas.retrieval.base.SlantColumn] = None, air_mass_factor: Optional[skdoas.retrieval.base.AirMassFactor] = None, cross_section: Optional[skdoas.retrieval.base.CrossSection] = None, ring_spectrum: Optional[skdoas.retrieval.base.RingSpectrum] = None, solar_spectrum: Optional[skdoas.retrieval.base.SolarSpectrum] = None, lineshape: Optional[skdoas.retrieval.base.LineShape] = None, atmosphere: Optional[skdoas.retrieval.base.Atmosphere] = None, box_air_mass_factor: Optional[skdoas.retrieval.base.BoxAirMassFactor] = None)

This retrieval is based on the OMI Version 2.1 NO2 standard product described in Bucsela et al 2013.

Includes:

  • slant column fitting in the 405 to 465 nm window considering NO2, H2O, O3 and the Ring effect

  • equivalent air mass factor formulation (in altitude rather than pressure) with a NO2 temperature correction

  • full SCD error analysis

  • full AMF error analysis

Does not (yet) include:

  • ability to deal with cloud cover

  • troposphere-stratosphere separation

References

E. J. Bucsela, N. A. Krotkov, E. A. Celarier, L. N. Lamsal, W. H. Swartz, P. K. Bhartia, K. F. Boersma, J. P. Veefkind, J. F. Gleason, and K. E. Pickering. A new stratospheric and tropospheric NO2 retrieval algorithm for nadir-viewing satellite instruments: application to OMI. Atmospheric Measurement Techniques, 6, 2607-2626, 2013.

OMI NO2 Standard Product V2.1 - Tropospheric Column

class skdoas.retrieval.omno2.Retrieval_OMNO2(slant_column: Optional[skdoas.retrieval.base.SlantColumn] = None, air_mass_factor: Optional[skdoas.retrieval.base.AirMassFactor] = None, cross_section: Optional[skdoas.retrieval.base.CrossSection] = None, ring_spectrum: Optional[skdoas.retrieval.base.RingSpectrum] = None, solar_spectrum: Optional[skdoas.retrieval.base.SolarSpectrum] = None, lineshape: Optional[skdoas.retrieval.base.LineShape] = None, atmosphere: Optional[skdoas.retrieval.base.Atmosphere] = None, box_air_mass_factor: Optional[skdoas.retrieval.base.BoxAirMassFactor] = None)

This retrieval is based on the OMI Version 2.1 NO2 standard product described in Bucsela et al 2013. Stratosphere-troposphere separation (STS) is done simply with an assumed NO2 profile and tropopause altitude - the STS algorithm described in Bucsela et al 2013 is not used.

Includes:

  • slant column fitting in the 405 to 465 nm window considering NO2, H2O, O3 and the Ring effect

  • equivalent air mass factor formulation (in altitude rather than pressure) with a NO2 temperature correction

  • simplified stratosphere-troposphere separation

  • full SCD error analysis

  • full AMF error analysis

Does not (yet) include:

  • ability to deal with cloud cover

References

E. J. Bucsela, N. A. Krotkov, E. A. Celarier, L. N. Lamsal, W. H. Swartz, P. K. Bhartia, K. F. Boersma, J. P. Veefkind, J. F. Gleason, and K. E. Pickering. A new stratospheric and tropospheric NO2 retrieval algorithm for nadir-viewing satellite instruments: application to OMI. Atmospheric Measurement Techniques, 6, 2607-2626, 2013.

OMI DOAS Total Ozone Prodcut

class skdoas.retrieval.omdoao3.Retrieval_OMDOAO3(slant_column: Optional[skdoas.retrieval.base.SlantColumn] = None, air_mass_factor: Optional[skdoas.retrieval.base.AirMassFactor] = None, cross_section: Optional[skdoas.retrieval.base.CrossSection] = None, lineshape: Optional[skdoas.retrieval.base.LineShape] = None, atmosphere: Optional[skdoas.retrieval.base.Atmosphere] = None, box_air_mass_factor: Optional[skdoas.retrieval.base.BoxAirMassFactor] = None)

This retrieval is based on the OMI DOAS total ozone algorithm described in Veefkind et al 2006.

Includes:

  • slant column fitting in the 331.6 to 336.6 nm window considering temperature-dependent O3 cross sections

  • a retrieved effective temperature (an average weighted according to ozone concentration)

  • SCD error anlysis

Does not (yet) include:

  • ability to deal with cloud cover

  • ring effect

  • full AMF error analysis

References

J. P. Veefkind, J. F. de Haan, E. J. Brinksma, M. Kroon, and P. F. Levelt. Total Ozone From the Ozone Monitoring Instrument (OMI) Using the DOAS Technique. IEEE Transactions on Geoscience and Remote Sensing, 44(5), 1239-1244, 2006.