S5_L2_CH4

Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of S5_L2_CH4 data.

field name

type

dimensions

unit

description

datetime_start

double

{time}

[seconds since 2010-01-01]

start time 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]

the four latitude boundaries of each ground pixel

longitude_bounds

float

{time, 4}

[degree_east]

the four longitude boundaries of each ground pixel

sensor_latitude

float

{time}

[degree_north]

latitude of the spacecraft sub-satellite point on the WGS84 reference ellipsoid

sensor_longitude

float

{time}

[degree_east]

longitude of the spacecraft sub-satellite point on the WGS84 reference ellipsoid

sensor_altitude

float

{time}

[m]

altitude of the spacecraft relative to the WGS84 reference ellipsoid.

sensor_orbit_phase

double

{time}

[]

relative offset (0.0 … 1.0) of the measurement in the orbit.

solar_zenith_angle

float

{time}

[degree]

zenith angle of the sun measured from the ground pixel location on the WGS84 reference ellipsoid

solar_azimuth_angle

float

{time}

[degree]

azimuth angle of the sun measured from the ground pixel location on the WGS84 ellipsoid

sensor_zenith_angle

float

{time}

[degree]

zenith angle of the spacecraft measured from the ground pixel location on the WGS84 reference ellipsoid

sensor_azimuth_angle

float

{time}

[degree]

azimuth angle of the spacecraft measured from the ground pixel WGS84 reference ellipsoid

surface_altitude

float

{time}

[m]

height of the surface above WGS84 ellipsoid averaged over the S5 pixel

surface_altitude_uncertainty

float

{time}

[m]

standard deviation of the height of the surface above WGS84 ellipsoid averaged over the S5 pixel

surface_pressure

float

{time}

[Pa]

surface pressure; from ECMWF and adjusted for surface elevation

surface_type

int32

{time}

surface classification

snow_ice_type

int32

{time}

surface condition (snow/ice); 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)

CH4_column_volume_mixing_ratio_dry_air

float

{time}

[ppbv]

physics CH4 dry air column mixing ratio

CH4_column_volume_mixing_ratio_dry_air_uncertainty

float

{time}

[ppbv]

physics CH4 dry air column mixing ratio noise estimate

CH4_column_volume_mixing_ratio_dry_air_validity

int32

{time}

quality assurance value describing the quality of the product

pressure

float

{time, vertical}

[Pa]

pressure grid

altitude

float

{time, vertical}

[m]

altitude grid

dry_air_column_number_density

float

{time}

[mol/m2]

column number density profile of dry air

CH4_column_number_density_apriori

float

{time, vertical}

[mol/m2]

a-priori CH4 profile

CO2_column_number_density_apriori

float

{time, vertical}

[mol/m2]

a-priori CO2 profile

O2_column_number_density_apriori

float

{time}

[mol/m2]

a-priori O2 column

H2O_column_number_density_apriori

float

{time}

[mol/m2]

a-priori H2O column

solar_induced_fluorescence

float

{time, spectral}

[]

solar induced fluorescence

CH4_column_number_density_avk

float

{time, vertical}

[]

physics CH4 column averaging kernel

H2O_column_number_density

float

{time}

[mol/m^2]

H2O column

CO2_column_number_density

float

{time}

[mol/m^2]

CO2 column

CO_column_number_density

float

{time}

[mol/m^2]

CO column

aerosol_effective_radius

float

{time}

[m]

aerosol particle size

aerosol_column_number_density

float

{time}

[mol/m^2]

Aerosol particle column

aerosol_height

float

{time}

[m]

aerosol layer height above the surface

surface_albedo

float

{time}

[]

surface albedo in the selected band

index

int32

{time}

zero-based index of the sample within the source product

Ingestion options

The table below lists the available ingestion options for S5_L2_CH4 products.

option name

legal values

description

ch4

physics, proxy

which CH4 column to ingest: ‘physics’ (default physics-based column) or ‘proxy’ (alternate proxy column)

band

SWIR-1, SWIR-3, NIR-2

Choose which surface albedo to ingest: SWIR-1 (default), SWIR-3, or NIR-2

Mapping description

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

field name

mapping description

datetime_start

path

/data/PRODUCT/time, /data/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)

orbit_index

path

/@orbit_start

validity

path

/data/PRODUCT/processing_quality_flags[]

description

the uint64 data is cast to int32

latitude

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/latitude[]

longitude

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/longitude[]

latitude_bounds

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/latitude_bounds[]

longitude_bounds

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/longitude_bounds[]

sensor_latitude

path

/data/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

/data/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

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/satellite_altitude[]

description

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

sensor_orbit_phase

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/satellite_orbit_phase[]

solar_zenith_angle

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/solar_zenith_angle[]

solar_azimuth_angle

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/solar_azimuth_angle[]

sensor_zenith_angle

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/viewing_zenith_angle[]

sensor_azimuth_angle

path

/data/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/viewing_azimuth_angle[]

surface_altitude

path

/data/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_altitude[]

surface_altitude_uncertainty

path

data/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_altitude_precision[]

surface_pressure

path

data/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_pressure[]

surface_type

path

/data/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_classification[]

snow_ice_type

condition

band=band3a or band unset

path

/data/PRODUCT_BAND3A/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

condition

band=band3c

path

/data/PRODUCT_BAND3C/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

condition

band=band3a or band unset

path

/data/PRODUCT_BAND3A/SUPPORT_DATA/INPUT_DATA/snow_ice_flag[]

description

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

condition

band=band3c

path

/data/PRODUCT_BAND3C/SUPPORT_DATA/INPUT_DATA/snow_ice_flag[]

description

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

CH4_column_volume_mixing_ratio_dry_air

condition

ch4=physics

path

data/PRODUCT/methane_dry_air_column_mixing_ratio_physics[]

condition

ch4=proxy

path

data/PRODUCT/methane_dry_air_column_mixing_ratio_proxy[]

CH4_column_volume_mixing_ratio_dry_air_uncertainty

condition

ch4=physics

path

data/PRODUCT/methane_dry_air_column_mixing_ratio_precision_physics[]

condition

ch4=proxy

path

data/PRODUCT/methane_dry_air_column_mixing_ratio_precision_proxy[]

CH4_column_volume_mixing_ratio_dry_air_validity

path

data/PRODUCT/qa_value

pressure

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/pressure[]

description

the vertical grid is inverted to make it ascending

altitude

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/altitude[]

description

the vertical grid is inverted to make it ascending

dry_air_column_number_density

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/dry_air_column[]

CH4_column_number_density_apriori

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/methane_profile_apriori[]

description

the vertical grid is inverted to make it ascending

CO2_column_number_density_apriori

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/carbon_dioxide_profile_apriori[]

description

the vertical grid is inverted to make it ascending

O2_column_number_density_apriori

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/oxygen_total_column_apriori[]

H2O_column_number_density_apriori

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/water_total_column_apriori[]

solar_induced_fluorescence

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/solar_induced_fluorescence[]

description

the spectral grid is inverted to make it ascending

CH4_column_number_density_avk

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/methane_total_column_averaging_kernel[]

description

the vertical grid is inverted to make it ascending

H2O_column_number_density

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/water_total_column[]

CO2_column_number_density

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/carbon_dioxide_total_column[]

CO_column_number_density

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/carbon_monoxide_total_column[]

aerosol_effective_radius

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_size[]

aerosol_column_number_density

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_particle_column[]

aerosol_height

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_layer_height[]

surface_albedo

condition

band=SWIR-1

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/surface_albedo_swir_1[]

condition

band=SWIR-3

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/surface_albedo_swir_3[]

condition

band=NIR-2

path

data/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/surface_albedo_nir_2[]