# EARLINET

## Variables

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

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime_start | double | {time} | [seconds since 1970-01-01] | start time of measurement
datetime_stop | double | {time} | [seconds since 1970-01-01] | stop time of measurement
latitude | float |  | [degrees] | latitude
longitude | float |  | [degrees] | longitude
sensor_altitude | float |  | [m] | sensor altitude
viewing_zenith_angle | float |  | [degrees] | viewing zenith angle
wavelength | float | {spectral} | [nm] | wavelength
altitude | double | {vertical} | [m] | altitude
backscatter_coefficient | double | {time, spectral, vertical} | [1/(m*sr)] | backscatter coefficient
backscatter_coefficient_uncertainty | double | {time, spectral, vertical} | [1/(m*sr)] | backscatter coefficient uncertainty
extinction_coefficient | double | {time, spectral, vertical} | [1/m] | extinction coefficient
extinction_coefficient_uncertainty | double | {time, spectral, vertical} | [1/m] | extinction coefficient uncertainty
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_start | path | /time_bounds[:,0]
datetime_stop | path | /time_bounds[:,1]
latitude | path | /latitude
longitude | path | /longitude
sensor_altitude | path | /station_altitude
viewing_zenith_angle | path | /zenith_angle
wavelength | path | /wavelength
altitude | path | /altitude
backscatter_coefficient | available | optional
path | /backscatter
backscatter_coefficient_uncertainty | available | optional
path | /error_backscatter
extinction_coefficient | available | optional
path | /extinction
extinction_coefficient_uncertainty | available | optional
path | /error_extinction