IAS_02_GHG

Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of IAS_02_GHG data.

field name	type	dimensions	unit	description
orbit_index	int32			absolute orbit number
ice_fraction	float	{time}	[]	fraction of IFOV covered by sea ice
land_fraction	float	{time}	[]	land fraction
surface_altitude	float	{time}	[m]	surface elevation
surface_altitude_uncertainty	float	{time}	[m]	standard deviation of surface elevation
datetime	double	{time}	[s since 2020-01-01]	on-board time in UTC
longitude	double	{time}	[degree_east]	geocentric longitude at sounder pixel centre
longitude_bounds	double	{time, 4}	[degree_east]	corner longitudes of the measurement
latitude	double	{time}	[degree_north]	geodetic latitude at sounder pixel centre
latitude_bounds	double	{time, 4}	[degree_north]	corner latitudes of the measurement
solar_azimuth_angle	double	{time}	[degree]	solar azimuth angle at sounder pixel centre
solar_zenith_angle	double	{time}	[degree]	solar zenith angle at sounder pixel centre
sensor_azimuth_angle	double	{time}	[degree]	measurement azimuth angle at sounder pixel centre
sensor_zenith_angle	double	{time}	[degree]	measurement zenith angle at sounder pixel centre
NO2_column_density	float	{time, vertical}	[kg/m2]	coarse N2O profile
CH4_column_density	float	{time, vertical}	[kg/m2]	coarse CH4 profile
CO2_column_density	float	{time, vertical}	[kg/m2]	coarse CO2 profile
index	int32	{time}		zero-based index of the sample within the source product

Mapping description

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

field name	mapping description
orbit_index	path	/@orbit_start
ice_fraction	path	/data/surface_info/ice_fraction[]
land_fraction	path	/data/surface_info/land_fraction[]
surface_altitude	path	/data/surface_info/height[]
surface_altitude_uncertainty	path	/data/surface_info/height_std[]
datetime	path	/data/geolocation_information/onboard_utc[]
longitude	path	/data/geolocation_information/sounder_pixel_longitude[]
longitude_bounds	path	/data/geolocation_information/sounder_pixel_longitude_bounds[]
	description	the corner coordinates are rough estimates of the circle areas for the scan elements; the size of a scan element (in a certain direction) is taken to be half the distance, from center to center, from a scan element to its nearest neighboring scan element (within the same 2x2 subgrid inside a Field of Regard (FOR))
latitude	path	/data/geolocation_information/sounder_pixel_latitude[]
latitude_bounds	path	/data/geolocation_information/sounder_pixel_latitude_bounds[]
	description	the corner coordinates are rough estimates of the circle areas for the scan elements; the size of a scan element (in a certain direction) is taken to be half the distance, from center to center, from a scan element to its nearest neighboring scan element (within the same 2x2 subgrid inside a Field of Regard (FOR))
solar_azimuth_angle	path	/data/geolocation_information/sounder_pixel_sun_azimuth[]
solar_zenith_angle	path	/data/geolocation_information/sounder_pixel_sun_zenith[]
sensor_azimuth_angle	path	/data/geolocation_information/sounder_pixel_azimuth[]
sensor_zenith_angle	path	/data/geolocation_information/sounder_pixel_zenith[]
NO2_column_density	path	/data/atmosphere_mass_content_of_nitrous_oxide[]
CH4_column_density	path	/data/atmosphere_mass_content_of_nitrous_oxide[]
CO2_column_density	path	/data/atmosphere_mass_content_of_nitrous_oxide[]