# ECA_ATL_ICE_2A

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `ECA_ATL_ICE_2A` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime | double | {time} | [seconds since 2000-01-01] | UTC time
latitude | double | {time} | [degree_north] | Geodetic latitude
longitude | double | {time} | [degree_east] | Geodetic longitude
orbit_index | int32 |  |  | absolute orbit number
altitude | float | {time, vertical} | [m] | joint standard grid height
surface_altitude | float | {time} | [m] | surface altitude
viewing_elevation_angle | float | {time} | [degree] | viewing elevation angle
tropopause_height | float | {time} | [m] | tropopause height
ice_water_density | float | {time, vertical} | [kg/m3] | ice water content
ice_water_density_uncertainty | float | {time, vertical} | [kg/m3] | ice water content error
ice_particle_effective_radius | float | {time, vertical} | [m] | ice effective radius
ice_particle_effective_radius_uncertainty | float | {time, vertical} | [m] | ice effective radius error
validity | int8 | {time, vertical} |  | quality status
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
--- | ---
datetime | path | /ScienceData/time
latitude | path | /ScienceData/latitude
longitude | path | /ScienceData/longitude
orbit_index | path | /HeaderData/VariableProductHeader/MainProductHeader/orbitNumber
altitude | path | /ScienceData/height, /ScienceData/geoid_offset
description | the vertical grid is inverted to make it ascending; altitude[i,j] = height[i,j] - geoid_offset[i]
surface_altitude | path | /ScienceData/elevation, /ScienceData/geoid_offset
description | altitude = elevation - geoid_offset
viewing_elevation_angle | path | /ScienceData/viewing_elevation_angle
tropopause_height | path | /ScienceData/tropopause_height
ice_water_density | path | /ScienceData/ice_water_content
description | the vertical grid is inverted to make it ascending
ice_water_density_uncertainty | path | /ScienceData/ice_water_content_error
description | the vertical grid is inverted to make it ascending
ice_particle_effective_radius | path | /ScienceData/ice_effective_radius
description | the vertical grid is inverted to make it ascending
ice_particle_effective_radius_uncertainty | path | /ScienceData/ice_effective_radius_error
description | the vertical grid is inverted to make it ascending
validity | path | /ScienceData/quality_status
description | the vertical grid is inverted to make it ascending