# CALIPSO_L2_CAL_LID_ALay

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `CALIPSO_L2_CAL_LID_ALay` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime_start | double | {time} | [seconds since 2000-01-01] | time at the start of the measurement
datetime | double | {time} | [seconds since 2000-01-01] | time during midpoint of the measurement
datetime_stop | double | {time} | [seconds since 2000-01-01] | time at the end 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
tropopause_altitude | double | {time} | [km] | tropopause altitude
solar_zenith_angle | double | {time} | [degree] | solar zenith angle
solar_azimuth_angle | double | {time} | [degree] | solar azimuth angle
viewing_elevation_angle | double | {time} | [degree] | viewing elevation angle
scattering_angle | double | {time} | [degree] | scattering angle
altitude | double | {time, vertical} | [km] | altitude of the middle of the layer
altitude_bounds | double | {time, vertical, 2} | [km] | altitudes at the base and the top of the layer
pressure | double | {time, vertical} | [hPa] | pressure at the middle of the layer
pressure_bounds | double | {time, vertical, 2} | [hPa] | pressures at the base and the top of the layer
temperature | double | {time, vertical} | [K] | temperature at the middle of the layer
tropospheric_aerosol_optical_depth | double | {time} | [] | tropospheric aerosol optical depth
tropospheric_aerosol_optical_depth_uncertainty | double | {time} | [] | tropospheric aerosol optical depth uncertainty
stratospheric_aerosol_optical_depth | double | {time} | [] | stratospheric aerosol optical depth
stratospheric_aerosol_optical_depth_uncertainty | double | {time} | [] | stratospheric aerosol optical depth uncertainty
cloud_optical_depth | double | {time} | [] | cloud optical depth
cloud_optical_depth_uncertainty | double | {time} | [] | cloud optical depth uncertainty
index | int32 | {time} |  | zero-based index of the sample within the source product

## Ingestion options

The table below lists the available ingestion options for `CALIPSO_L2_CAL_LID_ALay` products.

option name | legal values | description
--- | --- | ---
wavelength | 532, 1064 | the wavelength whose measurements are ingested; option values are ‘532’ (default), ‘1064’

## Mapping description

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

field name | mapping description
--- | ---
datetime_start | path | /Profile_Time[,0]
description | time at the start of the measurement
datetime | path | /Profile_Time[,N/2]
datetime_stop | path | /Profile_Time[,N-1]
description | time at the end of the measurement
latitude | path | /Latitude[,N/2]
longitude | path | /Longitude[,N/2]
tropopause_altitude | path | /Tropopause_Height[]
solar_zenith_angle | path | /Solar_Zenith_Angle[]
solar_azimuth_angle | path | /Solar_Azimuth_Angle[]
viewing_elevation_angle | path | /Off_Nadir_Angle[]
scattering_angle | path | /Scattering_Angle[]
altitude | path | /Layer_Base_Altitude[,], /Layer_Top_Altitude[,]
description | The altitude is calculated as the mid-point between the base and top altitudes of the layer
altitude_bounds | path | /Layer_Base_Altitude[,], /Layer_Top_Altitude[,]
pressure | path | /Midlayer_Pressure[,]
description | pressure at the middle of the layer
pressure_bounds | path | /Layer_Base_Pressure[,], /Layer_Top_Pressure[,]
temperature | path | /Midlayer_Temperature[,]
description | temperature at the middle of the layer
tropospheric_aerosol_optical_depth | condition | wavelength=532 or wavelength unset
path | /Column_Optical_Depth_Tropospheric_Aerosols_532[]
condition | wavelength=1064
path | /Column_Optical_Depth_Tropospheric_Aerosols_1064[]
tropospheric_aerosol_optical_depth_uncertainty | condition | wavelength=532 or wavelength unset
path | /Column_Optical_Depth_Tropospheric_Aerosols_Uncertainty_532[]
condition | wavelength=1064
path | /Column_Optical_Depth_Tropospheric_Aerosols_Uncertainty_1064[]
stratospheric_aerosol_optical_depth | condition | wavelength=532 or wavelength unset
path | /Column_Optical_Depth_Stratospheric_Aerosols_532[]
condition | wavelength=1064
path | /Column_Optical_Depth_Stratospheric_Aerosols_1064[]
stratospheric_aerosol_optical_depth_uncertainty | condition | wavelength=532 or wavelength unset
path | /Column_Optical_Depth_Stratospheric_Aerosols_Uncertainty_532[]
condition | wavelength=1064
path | /Column_Optical_Depth_Stratospheric_Aerosols_Uncertainty_1064[]
cloud_optical_depth | path | /Column_Optical_Depth_Cloud_532[]
cloud_optical_depth_uncertainty | path | /Column_Optical_Depth_Cloud_Uncertainty_532[]