# IAS_02_CLD

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `IAS_02_CLD` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
orbit_index | int32 |  |  | absolute orbit number
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
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
cloud_top_pressure | float | {time} | [Pa] | cloud top pressure
cloud_top_temperature | float | {time} | [K] | cloud top temperature
cloud_fraction | float | {time} | [] | effective cloud fraction
ice_water_density | float | {time} | [g/m2] | cloud ice amount
liquid_water_density | float | {time} | [g/m2] | cloud liquid water amount
cloud_phase_type | int8 | {time} |  | cloud phase at cloud top; enumeration values: clear_sky (0), liquid (1), ice (2), mixed (3), supercooled (4)
liquid_particle_effective_radius | float | {time} | [m] | effective radius of cloud condensed water particles at cloud top
dust_aerosol_index | float | {time} | [] | indicator of dust (more likely for higher values)
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
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[]
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[]
cloud_top_pressure | path | /data/air_pressure_at_cloud_top[*,*,*,0]
cloud_top_temperature | path | /data/air_temperature_at_cloud_top[*,*,*,0]
cloud_fraction | path | /data/effective_cloud_fraction[*,*,*,0]
ice_water_density | path | /data/atmosphere_mass_content_of_cloud_ice[]
liquid_water_density | path | /data/atmosphere_mass_content_of_cloud_liquid[]
cloud_phase_type | path | /data/thermodynamic_phase_of_cloud_water_particles_at_cloud_top
liquid_particle_effective_radius | path | /data/effective_radius_of_cloud_condensed_water_particles_at_cloud_top[]
dust_aerosol_index | path | /data/dust_indicator[]