# OMI_L3_OMSO2e

## Variables

The table below lists the variables that are present in the HARP product that results from an ingestion of `OMI_L3_OMSO2e` data.

field name | type | dimensions | unit | description
--- | --- | --- | --- | ---
datetime_start | double | {time} | [seconds since 2000-01-01] | start time of the grid
datetime_length | double | {time} | [days] | length of the grid
longitude | double | {longitude} | [degree_east] | longitude of the grid cell mid-point (WGS84)
latitude | double | {latitude} | [degree_north] | latitude of the grid cell mid-point (WGS84)
radiative_cloud_fraction | double | {time, latitude, longitude} | [] | Cloud fraction
SO2_column_number_density | double | {time, latitude, longitude} | [] | SO2 column number density
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 | /HDFEOS/ADDITIONAL/FILE_ATTRIBUTES@TAI93At0zOfGranule
description | the time of the measurement converted from TAI93 to seconds since 2000-01-01T00:00:00
datetime_length | description | set to fixed value of 1
longitude | path | /HDFEOS/GRIDS/TotalColumnAmountSO2@GridSpacing, /HDFEOS/GRIDS/TotalColumnAmountSO2@NumberOfLongitudesInGrid
description | a uniformly increasing sequence on the interval (-180, 180)
latitude | path | /HDFEOS/GRIDS/TotalColumnAmountSO2@GridSpacing, /HDFEOS/GRIDS/TotalColumnAmountSO2@NumberOfLatitudesInGrid
description | a uniformly increasing sequence on the interval (-90, 90)
radiative_cloud_fraction | path | /HDFEOS/GRIDS/TotalColumnAmountSO2/Data_Fields/CloudRadianceFraction[]
SO2_column_number_density | path | /HDFEOS/GRIDS/TotalColumnAmountSO2/Data_Fields/ColumnAmountSO2[]