# AEOLUS_L2A_SCA

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `AEOLUS_L2A_SCA` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime | double | {time} | [seconds since 2000-01-01] | start time of observation
datetime_length | double | {time} | [s] | duration of the observation
orbit_index | int32 |  |  | absolute orbit number
latitude | double | {time, vertical} | [degree_north] | latitude of the bin center
longitude | double | {time, vertical} | [degree_east] | longitude of the bin center
altitude | double | {time, vertical} | [m] | altitude of the bin center
extinction_coefficient | double | {time, vertical} | [(1e-6)/m] | particle extinction
extinction_coefficient_uncertainty | double | {time, vertical} | [1/m] | uncertainty of the particle extinction
backscatter_coefficient | double | {time, vertical} | [(1e-6)/m/sr] | particle backscatter
backscatter_coefficient_uncertainty | double | {time, vertical} | [1/m/sr] | uncertainty of the particle backscatter
optical_depth | double | {time, vertical} | [] | particle local optical depth
optical_depth_uncertainty | double | {time, vertical} | [] | uncertainty of the particle local optical depth
validity | int8 | {time, vertical} |  | processing qc flag
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 | /sca_optical_properties[]/starttime
datetime_length | description | set to fixed value of 12 seconds
orbit_index | path | /mph/abs_orbit
latitude | path | /sca_optical_properties[]/geolocation_middle_bins[]/latitude
longitude | path | /sca_optical_properties[]/geolocation_middle_bins[]/longitude
altitude | path | /sca_optical_properties[]/geolocation_middle_bins[]/altitude
extinction_coefficient | path | /sca_optical_properties[]/sca_optical_properties[]/extinction
extinction_coefficient_uncertainty | path | /sca_pcd[]/profile_pcd_bins[]/extinction_variance
description | the square root of the variance is taken as uncertainty
backscatter_coefficient | path | /sca_optical_properties[]/sca_optical_properties[]/backscatter
backscatter_coefficient_uncertainty | path | /sca_pcd[]/profile_pcd_bins[]/backscatter_variance
description | the square root of the variance is taken as uncertainty
optical_depth | path | /sca_optical_properties[]/sca_optical_properties[]/lod
optical_depth_uncertainty | path | /sca_pcd[]/profile_pcd_bins[]/lod_variance
description | the square root of the variance is taken as uncertainty
validity | path | /sca_pcd[]/profile_pcd_bins[]/processing_qc_flag