# 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 | double | {time} | [seconds since 2000-01-01] | time of measurement
datetime_length | double | {time} | [s] | length of the measurement
latitude | double |  | [degrees] | latitude
longitude | double |  | [degrees] | longitude
sensor_altitude | double |  | [m] | sensor altitude
viewing_zenith_angle | double |  | [degrees] | viewing zenith angle
wavelength | double |  | [nm] | wavelength
altitude | double | {vertical} | [m] | altitude
dust_aerosol_top_height | double | {time} | [m] | dust layer top height
backscatter_coefficient | double | {time, vertical} | [1/(m*sr)] | backscatter coefficient
backscatter_coefficient_uncertainty | double | {time, vertical} | [1/(m*sr)] | backscatter coefficient uncertainty
extinction_coefficient | double | {time, vertical} | [1/m] | extinction coefficient
extinction_coefficient_uncertainty | double | {time, vertical} | [1/m] | extinction coefficient uncertainty
H2O_mass_mixing_ratio | double | {time, vertical} | [g/kg] | water mass mixing ratio
H2O_mass_mixing_ratio_uncertainty | double | {time, vertical} | [g/kg] | water mass mixing ratio 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 | condition | variable ‘Time’ available
path | /Time
description | converted from seconds sinds 1970 to seconds since 2000
condition | variable ‘Time’ unavailable
path | /@StartDate, /@StartTime_UT, /@StopTime_UT
description | convert yymmdd encoded integer value for StartDate to seconds since 2000; convert hhmmss encoded integer values for StartTime_UT and StopTime_UT to time-of-day values; use: date + (start_time + stop_time) / 2
datetime_length | available | optional
condition | variable ‘Time’ unavailable
path | /@StartTime_UT, /@StopTime_UT
description | convert ‘hhmmss’ encoded integer values for StartTime_UT and StopTime_UT to time-of-day values; use: stop_time - start_time
latitude | path | /@Latitude_degrees_north
longitude | path | /@Longitude_degrees_east
sensor_altitude | path | /@Altitude_meter_asl
viewing_zenith_angle | path | /@ZenithAngle_degrees
wavelength | path | /@DetectionWavelength_nm
altitude | path | /Altitude
dust_aerosol_top_height | available | optional
path | /DustLayerHeight
backscatter_coefficient | available | optional
path | /Backscatter
backscatter_coefficient_uncertainty | available | optional
path | /ErrorBackscatter
extinction_coefficient | available | optional
path | /Extinction
extinction_coefficient_uncertainty | available | optional
path | /ErrorExtinction
H2O_mass_mixing_ratio | available | optional
path | /WaterVaporMixingRatio
H2O_mass_mixing_ratio_uncertainty | available | optional
path | /ErrorWaterVapor