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 last layer included for the tropospheric column

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

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

scene_albedo

float

{time}

[]

scene albedo

scene_pressure

float

{time}

[Pa]

apparent scene 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

land_fraction

float

{time}

[]

land fraction

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

data

o22cld

whether to ingest the NO2 data (default) or the O2-O2 cloud data (data=o22cld)

total_column

summed, total

whether to use nitrogendioxide_total_column (which is derived from the total slant column divided 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’

tropospheric_column

regular, lower

whether to ingest the regular tropospheric colum and related averaging kernel, or the lower tropospheric one (introduces with processor version 03.00.00); option values are ‘regular’ (default) and ‘lower’

cloud_fraction

radiance

whether to ingest the cloud fraction (default) or the radiance cloud fraction (cloud_fraction=radiance) for the NO2 data

This definition is only applicable when: data unset

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

condition

tropospheric_column=regular or tropospheric_column is unset

path

/PRODUCT/nitrogendioxide_tropospheric_column[]

condition

tropospheric_column=lower and processor version >= 03.00.00

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_lower_tropospheric_column[]

tropospheric_NO2_column_number_density_uncertainty

condition

tropospheric_column=regular or tropospheric_column is unset

path

/PRODUCT/nitrogendioxide_tropospheric_column_precision[]

condition

tropospheric_column=lower and processor version >= 03.00.00

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_lower_tropospheric_column_precision_kernel[]

tropospheric_NO2_column_number_density_validity

path

/PRODUCT/qa_value

tropospheric_NO2_column_number_density_amf

condition

tropospheric_column=regular or tropospheric_column is unset

path

/PRODUCT/air_mass_factor_troposphere[]

condition

tropospheric_column=lower and processor version >= 03.00.00

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/air_mass_factor_lower_troposphere[]

tropospheric_NO2_column_number_density_avk

condition

tropospheric_column=regular or tropospheric_column is unset

path

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

condition

tropospheric_column=lower and processor version >= 03.00.00

path

/PRODUCT/averaging_kernel[], /PRODUCT/air_mass_factor_total[], /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/air_mass_factor_lower_troposphere[], /PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/tm5_lower_troposphere_layer_index[]

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

scene_albedo

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/scene_albedo

scene_pressure

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/apparent_scene_pressure

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[]

land_fraction

available

optional

condition

processor version >= 02.09.00

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/land_fraction[]

snow_ice_type

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/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/INPUT_DATA/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[]