# ESACCI_GHG_L2_EMMA

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `ESACCI_GHG_L2_EMMA` 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
sensor_zenith_angle | double | {time} | [degree] | sensor zenith angle
solar_zenith_angle | double | {time} | [degree] | solar zenith angle
CH4_column_volume_mixing_ratio | double | {time} | [ppbv] | CH4 column volume mixing ratio
CH4_column_volume_mixing_ratio_uncertainty | double | {time} | [ppbv] | CH4 column volume mixing ratio uncertainty
CO2_column_volume_mixing_ratio | double | {time} | [ppmv] | CO2 column volume mixing ratio
CO2_column_volume_mixing_ratio_uncertainty | double | {time} | [ppmv] | CO2 column volume 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 | path | time[]
latitude | path | latitude[]
longitude | path | longitude[]
sensor_zenith_angle | available | optional
path | sensor_zenith_angle[]
solar_zenith_angle | available | optional
path | solar_zenith_angle[]
CH4_column_volume_mixing_ratio | available | optional
path | xch4[]
CH4_column_volume_mixing_ratio_uncertainty | available | optional
path | xch4_uncertainty[]
CO2_column_volume_mixing_ratio | available | optional
path | xco2[]
CO2_column_volume_mixing_ratio_uncertainty | available | optional
path | xco2_uncertainty[]