# ESACCI_AEROSOL_L2_ATSR2

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `ESACCI_AEROSOL_L2_ATSR2` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime | double | {time} | [seconds since 2000-01-01] | time of the measurement
latitude | double | {time} | [degree_north] | latitude of the ground pixel center
longitude | double | {time} | [degree_east] | longitude of the ground pixel center
latitude_bounds | double | {time, 4} | [degree_north] | corner latitudes for the ground pixel of the measurement
longitude_bounds | double | {time, 4} | [degree_east] | corner longitudes for the ground pixel of the measurement
aerosol_optical_depth | double | {time, spectral} | [] | aerosol optical depth
aerosol_optical_depth_uncertainty | double | {time, spectral} | [] | uncertainty of the aerosol optical depth
wavelength | double | {time, spectral} | [nm] | wavelengths of the measurements
sensor_zenith_angle | double | {time} | [degree] | sensor zenith angle for nadir view
solar_zenith_angle | double | {time} | [degree] | solar zenith angle for nadir view
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 | /time[]
latitude | path | /latitude[]
longitude | path | /longitude[]
latitude_bounds | path | /pixel_corner_latitude1[], /pixel_corner_latitude2[], /pixel_corner_latitude3[], /pixel_corner_latitude4[]
description | corner latitudes for the ground pixel of the measurement
longitude_bounds | path | /pixel_corner_longitude1[], /pixel_corner_longitude2[], /pixel_corner_longitude3[], /pixel_corner_longitude4[]
description | corner longitudes for the ground pixel of the measurement
aerosol_optical_depth | path | /AOD550[], /AOD670[], /AOD870[], /AOD1600[]
aerosol_optical_depth_uncertainty | path | /AOD550_uncertainty[], /AOD670_uncertainty[], /AOD870_uncertainty[], /AOD1600_uncertainty[]
description | depending on how the data is processed, uncertainty data is not always available for all wavelengths. If the data is not available, NaN values are used.
wavelength | description | fixed values
sensor_zenith_angle | available | optional
path | /satellite_zenith_at_center[]
solar_zenith_angle | available | optional
path | /sun_zenith_at_center[]