S4-L2-NO2
Variables
The table below lists the variables that are present in the HARP product that results from an ingestion of S4-L2-NO2 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 |
|
pressure_bounds |
float |
{time, vertical, 2} |
[Pa] |
pressure boundaries per profile layer |
snow_ice_type |
int8 |
{time} |
surface snow/ice type; enumeration values: snow_free_land (0), snow_ice (1) |
|
cloud_fraction |
float |
{time} |
[] |
cloud fraction |
cloud_fraction_uncertainty |
float |
{time} |
[] |
standard error of cloud fraction |
cloud_top_pressure |
float |
{time} |
[Pa] |
cloud top pressure |
cloud_top_pressure_uncertainty |
float |
{time} |
[Pa] |
standard error of cloud top pressure |
cloud_height |
float |
{time} |
[m] |
cloud height |
cloud_height_uncertainty |
float |
{time} |
[m] |
standard error of cloud height |
cloud_albedo |
float |
{time} |
[] |
cloud albedo |
cloud_albedo_uncertainty |
float |
{time} |
[] |
standard error of cloud albedo |
NO2_column_number_density |
float |
{time} |
[mol/m2] |
mole content of nitrogen dioxide |
NO2_column_number_density_uncertainty |
float |
{time} |
[mol/m2] |
standard error of mole content of nitrogen dioxide |
NO2_column_number_density_avk |
float |
{time, vertical} |
[] |
averaging kernel for the mole content of nitrogen dioxide |
stratospheric_NO2_column_number_density |
float |
{time} |
[mol/m2] |
troposphere mole content of nitrogen dioxide |
stratospheric_NO2_column_number_density_amf |
float |
{time} |
[] |
stratospheric air mass factor |
tropospheric_NO2_column_number_density |
float |
{time} |
[mol/m2] |
troposphere mole content of nitrogen dioxide |
tropospheric_NO2_column_number_density_uncertainty |
float |
{time} |
[mol/m2] |
standard error of troposphere mole content of nitrogen dioxide |
tropospheric_NO2_column_number_density_amf |
float |
{time} |
[] |
tropospheric air mass factor |
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-NO2 products.
option name |
legal values |
description |
|---|---|---|
total_column |
summed, total |
whether to use nitrogen_dioxide_doas_total_column (which is derived from the total slant column divided by the total amf) or nitrogen_dioxide_summed_total_column (which is the sum of the retrieved tropospheric and stratospheric columns); option values are ‘summed’ (default) and ‘total’ |
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[] |
pressure_bounds |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/constant_a_interface[], /PRODUCT/SUPPORT_DATA/INPUT_DATA/constant_b_interface[], /PRODUCT/SUPPORT_DATA/INPUT_DATA/surface_pressure[] |
description |
pressure bounds for layer k are derived as: (constant_a_interface[k] + constant_b_interface[k] * surface_pressure, constant_a_interface[k+1] + constant_b_interface[k+1] * surface_pressure) |
|
snow_ice_type |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/snow_ice_flag[] |
description |
0: snow_free_land, 1: snow_ice |
|
cloud_fraction |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_fraction[] |
cloud_fraction_uncertainty |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_fraction_precision[] |
cloud_top_pressure |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_pressure[] |
cloud_top_pressure_uncertainty |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_pressure_precision[] |
cloud_height |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_height[] |
cloud_height_uncertainty |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_height_precision[] |
cloud_albedo |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_albedo[] |
cloud_albedo_uncertainty |
path |
/PRODUCT/SUPPORT_DATA/INPUT_DATA/cloud_albedo_precision[] |
NO2_column_number_density |
condition |
total_column=summed or total_column unset |
path |
/PRODUCT/nitrogen_dioxide_summed_total_column[] |
|
condition |
total_column=total |
|
path |
/PRODUCT/nitrogen_dioxide_doas_total_column[] |
|
NO2_column_number_density_uncertainty |
available |
optional |
condition |
total_column=total |
|
path |
/PRODUCT/nitrogen_dioxide_doas_total_column_precision[] |
|
NO2_column_number_density_avk |
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/averaging_kernel[] |
description |
most likely corresponds to the DOAS total column |
|
stratospheric_NO2_column_number_density |
path |
/PRODUCT/nitrogen_dioxide_stratospheric_column[] |
stratospheric_NO2_column_number_density_amf |
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogen_dioxide_stratospheric_air_mass_factor[] |
tropospheric_NO2_column_number_density |
path |
/PRODUCT/nitrogen_dioxide_tropospheric_column[] |
tropospheric_NO2_column_number_density_uncertainty |
path |
/PRODUCT/nitrogen_dioxide_tropospheric_column_precision[] |
tropospheric_NO2_column_number_density_amf |
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogen_dioxide_tropospheric_air_mass_factor[] |