S4-L2-ALH
Variables
The table below lists the variables that are present in the HARP product that results from an ingestion of S4-L2-ALH 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) |
|
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 |
aerosol_height |
float |
{time} |
[m] |
height at center of aerosol layer |
aerosol_height_uncertainty |
float |
{time} |
[m] |
standard error of height at center of aerosol layer |
aerosol_pressure |
float |
{time} |
[Pa] |
assumed layer pressure thickness |
aerosol_pressure_uncertainty |
float |
{time} |
[Pa] |
standard error of assumed layer pressure thickness |
aerosol_optical_depth |
float |
{time} |
[] |
aerosol optical thickness |
aerosol_optical_depth_uncertainty |
float |
{time} |
[] |
standard error of aerosol optical thickness |
surface_albedo |
float |
{time} |
[] |
surface 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-ALH products.
option name |
legal values |
description |
|---|---|---|
surface_albedo |
770 |
whether to ingest the surface albedo at 758nm (default) or the surface alebedo at 770nm (surface_albedo=770) |
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 |
|
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[] |
aerosol_height |
path |
/PRODUCT/aerosol_mid_height[] |
aerosol_height_uncertainty |
path |
/PRODUCT/aerosol_mid_height_precision[] |
aerosol_pressure |
path |
/PRODUCT/aerosol_mid_pressure[] |
aerosol_pressure_uncertainty |
path |
/PRODUCT/aerosol_mid_pressure_precision[] |
aerosol_optical_depth |
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_optical_thickness[] |
aerosol_optical_depth_uncertainty |
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/aerosol_optical_thickness_precision[] |
surface_albedo |
condition |
surface_albedo unset |
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/surface_albedo[..,0] |
|
condition |
surface_albedo=770 |
|
path |
/PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/surface_albedo[..,1] |
|