cmaqsatproc.readers.omi package

Module contents

class cmaqsatproc.readers.omi.OMHCHO[source]

Bases: OMIL2

OMHCHO satellite processor. * bbox subsets the nTimes and nTimes_1 dimensions * valid based three conditions

  • MainDataQualityFlag == 0

  • (XtrackQualityFlagsExpanded & 1) == 0

  • AMFCloudFraction <= 0.3

classmethod cmaq_ak(overf, satl3f)[source]

Calculate an averaging kernel (AK) that would process CMAQ as though it were observed by the satellite. In this case, the averaging kernel is the scattering weights divided by the tropospheric air mass factor.

Parameters:

  • overf (xarray.Dataset) – Must have PRES variable with LAY dimension that describes the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

Returns:

q_ak – Averaging kernel on the CMAQ grid

Return type:

xr.DataArray

classmethod cmaq_amf(overf, satl3f, key='FORM_PER_CM2')[source]

Calculate an alternative Air Mass Factor (AMF) using satellite scattering weights and the CMAQ vertical profile as a partial column density.

Parameters:

  • overf (xarray.Dataset) – Must have PRES variable with LAY dimension that describes the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

  • key (str) – Key of the partial column density variable from CMAQ, which must have a LAY dimension that describes teh vertical coordinate.

Returns:

cmaqamf – Air Mass Factor on the CMAQ grid

Return type:

xr.DataArray

classmethod cmaq_process(qf, satl3f, key='FORM')[source]

Process CMAQ as though it were observed by OMI and recualculate OMI tropospheric columns with the CMAQ AMF. This process relies

Parameters:

  • qf (xarray.Dataset) – CMAQ file that has composition (e.g., FORM), PRES, DENS, and ZF variables with a LAY dimension describing the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

  • key (str) – Key for composition data.

Returns:

overf – An overpass file with satellite-like CMAQ and CMAQ-like satellite.

Return type:

xr.DataArray

classmethod cmaq_sw(overf, satl3f)[source]

Interpolate satellite scattering weights to CMAQ vertical grid, based on PRES (pressure in Pa).

Parameters:

  • overf (xarray.Dataset) – Must have PRES variable with LAY dimension that describes the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

Returns:

q_sw – Scattering Weights on the CMAQ grid

Return type:

xr.DataArray

Thin wrapper around satellite.cmr_links where concept_id is set to “C1239966779-GES_DISC”.

Parameters:

method (str) – ‘opendap’, ‘download’, or ‘s3’. ‘s3’ is not supported for OMI at this time.

Returns:

links – List of links for download or OpenDAP

Return type:

list

classmethod open_dataset(path, bbox=None, **kwargs)[source]
Parameters:

  • path (str) – Path to a OMI OpenDAP-style file

  • bbox (iterable) – swlon, swlat, nelon, nelat in decimal degrees East and North of 0, 0

  • kwargs (mappable) – Passed to xarray.open_dataset

Returns:

sat – Satellite processing instance

Return type:

OMI

class cmaqsatproc.readers.omi.OMIL2[source]

Bases: satellite

Default OMI satellite processor. * bbox subsets the nTimes and nTimes_1 dimensions

classmethod open_dataset(path, bbox=None, **kwargs)[source]
Parameters:

  • path (str) – Path to a OMI OpenDAP-style file

  • bbox (iterable) – swlon, swlat, nelon, nelat in decimal degrees East and North

  • kwargs (mappable) – Passed to xarray.open_dataset

Returns:

sat – Satellite processing instance

Return type:

OMIL2

classmethod prep_dataset(ds, bbox=None, path=None)[source]

Applies spatial subset based on Latitude and Longitude

Parameters:

  • ds (xarray.Dataset) – Satellite dataset

  • bbox (iterable) – swlon, swlat, nelon, nelat in decimal degrees East and North

  • path (str) – Unused.

Returns:

ds

Return type:

xarray.Dataset

classmethod shorten_name(key)[source]

Provide a short name for long keys. This is useful for renaming variables to fit IOAPI 16 character restrictions.

Parameters:

key (str) – Original variable name.

Returns:

shortkey – Shortened key

Return type:

str

class cmaqsatproc.readers.omi.OMNO2[source]

Bases: OMIL2

OMNO2 satellite processor. * bbox subsets the nTimes and nTimes_1 dimensions * valid based three conditions

  • (VcdQualityFlags & 1) == 0

  • XTrackQualityFlags == 0

  • CloudFraction <= 0.3

classmethod cmaq_ak(overf, satl3f)[source]

Calculate an averaging kernel (AK) that would process CMAQ as though it were observed by the satellite. In this case, the averaging kernel is the scattering weights divided by the tropospheric air mass factor.

Parameters:

  • overf (xarray.Dataset) – Must have PRES variable with LAY dimension that describes the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

Returns:

q_ak – Averaging kernel on the CMAQ grid

Return type:

xr.DataArray

classmethod cmaq_amf(overf, satl3f, key='NO2_PER_CM2')[source]

Calculate an alternative Air Mass Factor (AMF) using satellite scattering weights and the CMAQ vertical profile as a partial column density.

Parameters:

  • overf (xarray.Dataset) – Must have PRES variable with LAY dimension that describes the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

  • key (str) – Key of the partial column density variable from CMAQ, which must have a LAY dimension that describes teh vertical coordinate.

Returns:

cmaqamf – Air Mass Factor on the CMAQ grid

Return type:

xr.DataArray

classmethod cmaq_process(qf, satl3f, key='NO2')[source]

Process CMAQ as though it were observed by OMI and recualculate OMI tropospheric columns with the CMAQ AMF. This process relies

Parameters:

  • qf (xarray.Dataset) – CMAQ file that has composition (e.g., NO2), PRES, DENS, and ZF variables with a LAY dimension describing the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

Returns:

overf – An overpass file with satellite-like CMAQ and CMAQ-like satellite.

Return type:

xr.DataArray

classmethod cmaq_sw(overf, satl3f)[source]

Interpolate satellite scattering weights to CMAQ vertical grid, based on PRES (pressure in Pa).

Parameters:

  • overf (xarray.Dataset) – Must have PRES variable with LAY dimension that describes the vertical coordinate.

  • satl3f (xarray.Dataset) – Output from to_level3, paths_to_level3, or cmr_to_level3 with as_dataset=True (the default).

Returns:

q_sw – Scattering Weights on the CMAQ grid

Return type:

xr.DataArray

Thin wrapper around satellite.cmr_links where concept_id is set to “C1239966842-GES_DISC”.

Parameters:

method (str) – ‘opendap’, ‘download’, or ‘s3’. ‘s3’ is not supported for OMI at this time.

Returns:

links – List of links for download or OpenDAP

Return type:

list

classmethod open_dataset(path, bbox=None, **kwargs)[source]
Parameters:

  • path (str) – Path to a OMI OpenDAP-style file

  • bbox (iterable) – swlon, swlat, nelon, nelat in decimal degrees East and North of 0, 0

  • kwargs (mappable) – Passed to xarray.open_dataset

Returns:

sat – Satellite processing instance

Return type:

OMINO2

class cmaqsatproc.readers.omi.OMO3PR[source]

Bases: OMIL2

OMO3PR satellite processor. * bbox subsets the nTimes and nTimes_1 dimensions * valid based three conditions

  • MainDataQualityFlag == 0

  • (XtrackQualityFlagsExpanded & 1) == 0

  • AMFCloudFraction <= 0.3

Thin wrapper around satellite.cmr_links where concept_id is set to “C1239966827-GES_DISC”.

Parameters:

method (str) – ‘opendap’, ‘download’, or ‘s3’. ‘s3’ is not supported for OMI at this time.

Returns:

links – List of links for download or OpenDAP

Return type:

list

classmethod open_dataset(path, bbox=None, **kwargs)[source]
Parameters:

  • path (str) – Path to a OMI OpenDAP-style file

  • bbox (iterable) – swlon, swlat, nelon, nelat in decimal degrees East and North of 0, 0

  • kwargs (mappable) – Passed to xarray.open_dataset

Returns:

sat – Satellite processing instance

Return type:

OMI

class cmaqsatproc.readers.omi.OMPROFOZ[source]

Bases: OMIL2

OMPROFOZ satellite processor. * bbox subsets the nTimes and nTimes_1 dimensions * valid based three conditions

  • MainDataQualityFlag == 0

  • (XtrackQualityFlagsExpanded & 1) == 0

  • AMFCloudFraction <= 0.3

Thin wrapper around satellite.cmr_links where short_name is set to “OMPROFOZ”.

Parameters:

method (str) – ‘opendap’, ‘download’, or ‘s3’. ‘s3’ is not supported for OMI at this time.

Returns:

links – List of links for download or OpenDAP

Return type:

list

classmethod open_dataset(path, bbox=None, **kwargs)[source]
Parameters:

  • path (str) – Path to a OMI OpenDAP-style file

  • bbox (iterable) – swlon, swlat, nelon, nelat in decimal degrees East and North of 0, 0

  • kwargs (mappable) – Passed to xarray.open_dataset

Returns:

sat – Satellite processing instance

Return type:

OMI