S4-L2-AUI

Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of S4-L2-AUI data.

field name

type

dimensions

unit

description

scan_subindex

int16

{time}

pixel index (0-based) within the scanline

cycle_index

int32

repeat cycle number within the day

datetime

double

{time}

[seconds since 2000-01-01]

time of the measurement

datetime_length

double

[s]

measurement duration

latitude

float

{time}

[degree_north]

pixel center latitude

longitude

float

{time}

[degree_east]

pixel center longitude

latitude_bounds

float

{time, 4}

[degree_north]

latitudes of pixel boundary

longitude_bounds

float

{time, 4}

[degree_east]

longitudes of pixel boundary

validity

int8

{time}

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

solar_zenith_angle

float

{time}

[degree]

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

solar_azimuth_angle

float

{time}

[degree]

azimuth angle of the Sun at the ground pixel location; angle measured clockwise from North

viewing_zenith_angle

float

{time}

[degree]

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

viewing_azimuth_angle

float

{time}

[degree]

azimuth angle of the satellite at the ground pixel location; angle measured clockwise from North

surface_altitude

float

{time}

[m]

surface altitude

surface_altitude_uncertainty

float

{time}

[m]

standard error of surface altitude

surface_pressure

float

{time}

[Pa]

surface pressure

surface_type

int32

{time}

surface type classification

snow_ice_type

int8

{time}

surface snow/ice type; enumeration values: snow_free_land (0), snow_ice (1)

absorbing_aerosol_index

float

{time}

[]

aerosol index

absorbing_aerosol_index_uncertainty

float

{time}

[]

uncertainty of the aerosol index

scene_albedo

float

{time}

[]

scene albedo

index

int32

{time}

zero-based index of the sample within the source product

Ingestion options

The table below lists the available ingestion options for S4-L2-AUI products.

option name

legal values

description

wavelength_ratio

354_388nm, 340_380nm

ingest aerosol index retrieved at wavelengths 354/388 nm (default) or 354/388 nm (wavelength_ratio=340_380nm)

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 ground_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 pixels per scanline

cycle_index

path

/@repeat_cycle_in_day[0]

description

parsed from the string attribute repeat_cycle_in_day

datetime

path

/@time_reference_days_since_1950, /PRODUCT/delta_time[]

description

time reference converted from days since 1950-01-01 to seconds since 2000-01-01 (using 86400 seconds per day) and delta_time added

datetime_length

path

/PRODUCT/delta_time[]

description

delta_time[num_ground_pixels] - delta_time[0]

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[]

validity

path

/PRODUCT/qa_value

solar_zenith_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/solar_zenith_angle[]

solar_azimuth_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/solar_azimuth_angle[]

viewing_zenith_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/viewing_zenith_angle[]

viewing_azimuth_angle

path

/PRODUCT/SUPPORT_DATA/GEOLOCATIONS/viewing_azimuth_angle[]

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_type

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_classification[]

snow_ice_type

path

/PRODUCT/SUPPORT_DATA/INPUT_DATA/snow_ice_flag[]

description

0: snow_free_land, 1: snow_ice

absorbing_aerosol_index

condition

wavelength_ratio=354_388nm or wavelength_ratio unset

path

/PRODUCT/aerosol_index_354_388

condition

wavelength_ratio=340_380nm

path

/PRODUCT/aerosol_index_340_380

absorbing_aerosol_index_uncertainty

condition

wavelength_ratio=354_388nm or wavelength_ratio unset

path

/PRODUCT/aerosol_index_354_388_precision

condition

wavelength_ratio=340_380nm

path

/PRODUCT/aerosol_index_340_380_precision

scene_albedo

condition

wavelength_ratio=354_388nm or wavelength_ratio unset

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/scene_albedo_388[]

condition

wavelength_ratio=340_380nm

path

/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/scene_albedo_380[]