S5P_L2_NO2

Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of S5P_L2_NO2 data.

field name

type

dimensions

unit

description

scan_subindex

int16

{time}

pixel index (0-based) within the scanline

datetime_start

double

{time}

[seconds since 2010-01-01]

start time of the measurement

datetime_length

double

[s]

duration of the measurement

orbit_index

int32

absolute orbit number

validity

int32

{time}

processing quality flag

latitude

float

{time}

[degree_north]

latitude of the ground pixel center (WGS84)

longitude

float

{time}

[degree_east]

longitude of the ground pixel center (WGS84)

latitude_bounds

float

{time, 4}

[degree_north]

latitudes of the ground pixel corners (WGS84)

longitude_bounds

float

{time, 4}

[degree_east]

longitudes of the ground pixel corners (WGS84)

sensor_latitude

float

{time}

[degree_north]

latitude of the geodetic sub-satellite point (WGS84)

sensor_longitude

float

{time}

[degree_east]

longitude of the goedetic sub-satellite point (WGS84)

sensor_altitude

float

{time}

[m]

altitude of the satellite with respect to the geodetic sub-satellite point (WGS84)

solar_zenith_angle

float

{time}

[degree]

zenith angle of the Sun at the ground pixel location (WGS84); angle measured away from the vertical

solar_azimuth_angle

float

{time}

[degree]

azimuth angle of the Sun at the ground pixel location (WGS84); angle measured East-of-North

sensor_zenith_angle

float

{time}

[degree]

zenith angle of the satellite at the ground pixel location (WGS84); angle measured away from the vertical

sensor_azimuth_angle

float

{time}

[degree]

azimuth angle of the satellite at the ground pixel location (WGS84); angle measured East-of-North

pressure_bounds

double

{time, vertical, 2}

[Pa]

pressure boundaries

tropospheric_NO2_column_number_density

float

{time}

[mol/m^2]

tropospheric vertical column of NO2

tropospheric_NO2_column_number_density_uncertainty

float

{time}

[mol/m^2]

uncertainty of the tropospheric vertical column of NO2 (standard error)

tropospheric_NO2_column_number_density_validity

int8

{time}

continuous quality descriptor, varying between 0 (no data) and 100 (full quality data)

tropospheric_NO2_column_number_density_amf

float

{time}

[]

tropospheric air mass factor, computed by integrating the altitude dependent air mass factor over the atmospheric layers from the surface up to and including the layer with the tropopause

tropospheric_NO2_column_number_density_avk

float

{time, vertical}

[]

averaging kernel for the tropospheric vertical column number density of NO2

NO2_column_number_density

float

{time}

[mol/m^2]

total vertical column of NO2 (ratio of the slant column density of NO2 and the total air mass factor)

NO2_column_number_density_uncertainty

float

{time}

[mol/m^2]

uncertainty of the total vertical column of NO2 (standard error)

NO2_column_number_density_amf

float

{time}

[]

total air mass factor, computed by integrating the altitude dependent air mass factor over the atmospheric layers from the surface to top-of-atmosphere

NO2_column_number_density_avk

float

{time, vertical}

[]

averaging kernel for the air mass factor correction, describing the NO2 profile sensitivity of the vertical column density

stratospheric_NO2_column_number_density

float

{time}

[mol/m^2]

stratospheric vertical column of NO2

stratospheric_NO2_column_number_density_uncertainty

float

{time}

[mol/m^2]

uncertainty of the stratospheric vertical column of NO2 (standard error)

stratospheric_NO2_column_number_density_amf

float

{time}

[]

stratospheric air mass factor

stratospheric_NO2_column_number_density_avk

float

{time, vertical}

[]

averaging kernel for the stratospheric vertical column number density of NO2

NO2_slant_column_number_density

float

{time}

[mol/m^2]

slant column of NO2

NO2_slant_column_number_density_uncertainty

float

{time}

[mol/m^2]

uncertainty of the slant column of NO2

cloud_fraction

float

{time}

[]

cloud fraction for NO2 fitting window

absorbing_aerosol_index

float

{time}

[]

aerosol index

cloud_albedo

float

{time}

[]

cloud albedo

cloud_pressure

float

{time}

[Pa]

cloud pressure

surface_albedo

float

{time}

[]

surface albedo

surface_altitude

float

{time}

[m]

surface altitude

surface_altitude_uncertainty

float

{time}

[m]

surface altitude precision

surface_pressure

float

{time}

[Pa]

surface pressure

surface_meridional_wind_velocity

float

{time}

[m/s]

northward wind

surface_zonal_wind_velocity

float

{time}

[m/s]

eastward wind

snow_ice_type

int8

{time}

surface snow/ice type; enumeration values: snow_free_land (0), sea_ice (1), permanent_ice (2), snow (3), ocean (4)

sea_ice_fraction

float

{time}

[]

sea-ice concentration (as a fraction)

tropopause_pressure

double

{time}

[Pa]

tropopause pressure

index

int32

{time}

zero-based index of the sample within the source product

Ingestion options

The table below lists the available ingestion options for S5P_L2_NO2 products.

option name

legal values

description

total_column

summed, total

whether to use nitrogendioxide_total_column (which is derived from the total slant column diveded by the total amf) or nitrogendioxide_summed_total_column (which is the sum of the retrieved tropospheric and stratospheric columns); option values are ‘summed’ (default) and ‘total’

cloud_fraction

radiance

whether to ingest the cloud fraction (default) or the radiance cloud fraction (cloud_fraction=radiance)

Mapping description

The table below details where and how each variable was retrieved from the input product.

field name

mapping description

scan_subindex

description

the scanline and pixel dimensions are collapsed into a temporal dimension; the index of the pixel within the scanline is computed as the index on the temporal dimension modulo the number of scanlines

datetime_start

path

/PRODUCT/time, /PRODUCT/delta_time[]

description

time converted from milliseconds since a reference time (given as seconds since 2010-01-01) to seconds since 2010-01-01 (using 86400 seconds per day); the time associated with a scanline is repeated for each pixel in the scanline

datetime_length

path

/@time_coverage_resolution

description

the measurement length is parsed assuming the ISO 8601 ‘PT%(interval_seconds)fS’ format

orbit_index

path

/@orbit

validity

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/processing_quality_flags[]

description

the uint32 data is cast to int32

latitude

path

/PRODUCT/latitude[]

longitude

path

/PRODUCT/longitude[]

latitude_bounds

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/latitude_bounds[]

longitude_bounds

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/longitude_bounds[]

sensor_latitude

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/satellite_latitude[]

description

the satellite latitude associated with a scanline is repeated for each pixel in the scanline

sensor_longitude

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/satellite_longitude[]

description

the satellite longitude associated with a scanline is repeated for each pixel in the scanline

sensor_altitude

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/satellite_altitude[]

description

the satellite altitude associated with a scanline is repeated for each pixel in the scanline

solar_zenith_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/solar_zenith_angle[]

solar_azimuth_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/solar_azimuth_angle[]

sensor_zenith_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/viewing_zenith_angle[]

sensor_azimuth_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/viewing_azimuth_angle[]

pressure_bounds

path

/PRODUCT/tm5_constant_a[], /PRODUCT/tm5_constant_b[], /PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_pressure[]

description

pressure in Pa at level k is derived from surface pressure in Pa as: tm5_constant_a[k] + tm5_constant_b[k] * surface_pressure[]; the top of atmosphere pressure is clamped to 1e-3 Pa

tropospheric_NO2_column_number_density

path

/PRODUCT/nitrogendioxide_tropospheric_column[]

tropospheric_NO2_column_number_density_uncertainty

path

/PRODUCT/nitrogendioxide_tropospheric_column_precision[]

tropospheric_NO2_column_number_density_validity

path

/PRODUCT/qa_value

tropospheric_NO2_column_number_density_amf

path

/PRODUCT/air_mass_factor_troposphere[]

tropospheric_NO2_column_number_density_avk

path

/PRODUCT/averaging_kernel[], /PRODUCT/air_mass_factor_total[], /PRODUCT/air_mass_factor_troposphere[], /PRODUCT/tm5_tropopause_layer_index[]

description

averaging_kernel[layer] = if layer <= tm5_tropopause_layer_index then averaging_kernel[layer] * air_mass_factor_total / air_mass_factor_troposphere else 0

NO2_column_number_density

condition

total_column=summed or total_column unset

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_summed_total_column[]

condition

total_column=total

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_total_column[]

NO2_column_number_density_uncertainty

condition

total_column=summed or total_column unset

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_summed_total_column_precision[]

condition

total_column=total

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_total_column_precision[]

NO2_column_number_density_amf

path

/PRODUCT/air_mass_factor_total[]

NO2_column_number_density_avk

path

/PRODUCT/averaging_kernel[]

stratospheric_NO2_column_number_density

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_stratospheric_column[]

stratospheric_NO2_column_number_density_uncertainty

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_stratospheric_column_precision[]

stratospheric_NO2_column_number_density_amf

path

/PRODUCT/air_mass_factor_troposphere[]

stratospheric_NO2_column_number_density_avk

path

/PRODUCT/averaging_kernel[], /PRODUCT/air_mass_factor_total[], /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/air_mass_factor_stratosphere[], /PRODUCT/tm5_tropopause_layer_index[]

description

averaging_kernel[layer] = if layer > tm5_tropopause_layer_index then averaging_kernel[layer] * air_mass_factor_total / air_mass_factor_stratosphere else 0

NO2_slant_column_number_density

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_slant_column_density[]

NO2_slant_column_number_density_uncertainty

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_slant_column_density_precision[]

cloud_fraction

condition

cloud_fraction unset

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/cloud_fraction_crb_nitrogendioxide_window[]

condition

cloud_fraction=radiance

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/cloud_radiance_fraction_nitrogendioxide_window[]

absorbing_aerosol_index

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/aerosol_index_354_388

cloud_albedo

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_albedo_crb

cloud_pressure

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_pressure_crb

surface_albedo

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_albedo_nitrogendioxide_window

surface_altitude

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_altitude[]

surface_altitude_uncertainty

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_altitude_precision[]

surface_pressure

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_pressure[]

surface_meridional_wind_velocity

available

optional

condition

processor version >= 01.03.00

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/northward_wind[]

surface_zonal_wind_velocity

available

optional

condition

processor version >= 01.03.00

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/eastward_wind[]

snow_ice_type

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/snow_ice_flag[]

description

0: snow_free_land (0), 1-100: sea_ice (1), 101: permanent_ice (2), 103: snow (3), 255: ocean (4), other values map to -1

sea_ice_fraction

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/snow_ice_flag[]

description

if 1 <= snow_ice_flag <= 100 then snow_ice_flag/100.0 else 0.0

tropopause_pressure

path

/PRODUCT/tm5_constant_a[], /PRODUCT/tm5_constant_b[], /PRODUCT/tm5_tropopause_layer_index[], /PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_pressure[]

description

pressure in Pa at tropause is derived from the upper bound of the layer with tropopause layer index k: tm5_constant_a[k + 1] + tm5_constant_b[k + 1] * surface_pressure[]