# OCO_OCO2_L3CO2

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `OCO_OCO2_L3CO2` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime_start | double | {time} | [seconds since 2000-01-01] | range beginning date
datetime_length | double | {time} | [s] | averaging period
latitude | double | {latitude} | [degree_north] | latitude
longitude | double | {longitude} | [degree_east] | longitude
CO2_column_volume_mixing_ratio_dry_air | double | {time, latitude, longitude} | [ppmv] | Assimilated dry-air column average CO2 daily mean
CO2_column_volume_mixing_ratio_dry_air_uncertainty | double | {time, latitude, longitude} | [ppmv] | precission of XCO2 daily mean
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 | /@RangeBeginningDate, /@RangeBeginningTime
datetime_length | description | Fixed value of 86400
latitude | path | /lat[]
longitude | path | /lon[]
CO2_column_volume_mixing_ratio_dry_air | path | /XCO2[]
CO2_column_volume_mixing_ratio_dry_air_uncertainty | path | /XCO2PREC[]