# AEOLUS_L1B_Mie_Observation

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `AEOLUS_L1B_Mie_Observation` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime_start | double | {time} | [seconds since 2000-01-01] | start time of the observation
datetime_length | double | {time} | [s] | duration of the observation
orbit_index | int32 |  |  | absolute orbit number
latitude | double | {time, vertical} | [degree_north] | average of the latitudes of the edges of the height bin
longitude | double | {time, vertical} | [degree_east] | average of the longitude of the edges of the height bin
altitude_bounds | double | {time, vertical, 2} | [m] | altitude boundaries of the height bin
geoid_height | double | {time} | [m] | Geoid separation
sensor_azimuth_angle | double | {time, vertical} | [degree] | average of the edges of the height bin of the azimuth of target-to-satellite topocentric pointing vector
sensor_elevation_angle | double | {time, vertical} | [degree] | average of the edges of the height bin of the elevation of target-to-satellite topocentric pointing vector
hlos_wind_velocity | double | {time, vertical} | [m/s] | HLOS wind velocity at the altitude bin
hlos_wind_velocity_validity | int32 | {time, vertical} |  | quality flag of the HLOS wind velocity at the altitude bin
index | int32 | {time} |  | zero-based index of the sample within the source product

## Ingestion options

The table below lists the available ingestion options for `AEOLUS_L1B` products.

option name | legal values | description
--- | --- | ---
data | rayleigh_measurement, mie_measurement, rayleigh_observation, mie_observation | the type of wind profile to ingest; option values are ‘rayleigh_observation’ (default), ‘mie_observation’, ‘rayleigh_measurement’, ‘mie_measurement’

This definition is only applicable when: data=mie_observation

## Mapping description

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

field name | mapping description
--- | ---
datetime_start | path | /geolocation[]/start_of_observation_time
datetime_length | description | set to fixed value of 12 seconds
orbit_index | path | /mph/abs_orbit
latitude | path | /geolocation[]/observation_geolocation[]/observation_mie_geolocation[]/latitude_of_height_bin
description | average of the value at the upper and lower edge of the height bin
longitude | path | /geolocation[]/observation_geolocation[]/observation_mie_geolocation[]/longitude_of_height_bin
description | average of the value at the upper and lower edge of the height bin
altitude_bounds | path | /geolocation[]/observation_geolocation[]/observation_mie_geolocation[]/altitude_of_height_bin, /geolocation[]/observation_geolocation/geoid_separation
description | altitude_of_height_bin minus geoid_separation (because altitude_of_height_bin is wrt WGS84)
geoid_height | path | /geolocation[]/observation_geolocation/geoid_separation
sensor_azimuth_angle | path | /geolocation[]/observation_geolocation[]/observation_mie_geolocation[]/topocentric_azimuth_of_height_bin
description | average of the value at the upper and lower edge of the height bin
sensor_elevation_angle | path | /geolocation[]/observation_geolocation[]/observation_mie_geolocation[]/topocentric_elevation_of_height_bin
description | average of the value at the upper and lower edge of the height bin
hlos_wind_velocity | path | /wind_velocity[]/observation_wind_profile[]/mie_altitude_bin_wind_info[]/wind_velocity
hlos_wind_velocity_validity | path | /wind_velocity[]/observation_wind_profile[]/mie_altitude_bin_wind_info[]/bin_quality_flag