DSCOVR EPIC L4 TrO3: Global Tropospheric Ozone Maps

DSCOVR_EPIC_L4_TrO3_01 is a NASA Level-4 data product providing synoptic maps of tropospheric ozone columns (TCO) derived from the Earth Polychromatic Imaging Camera (EPIC) on the Deep Space Climate Observatory (DSCOVR) spacecraft. The dataset contains gridded, hourly TCO measurements over the sunlit Earth, calculated by subtracting MERRA-2 stratospheric ozone from EPIC total ozone retrievals. Data are spatially averaged to a 1° latitude x 1° longitude grid and reported in Dobson Units (DU) within HDF5 files.

Use Cases

• Tracking global tropospheric ozone pollution transport based on 1-2 hour synoptic maps.
• Validating atmospheric chemistry models using independent satellite-derived ozone columns.
• Studying diurnal variations in near-surface ozone over the sunlit hemisphere.
• Analyzing long-term trends in tropospheric ozone from the 2015-present data record.

Strengths

• Provides unique, near-hourly global snapshots of tropospheric ozone from the sunlit side of Earth.
• Derived from a well-characterized instrument (EPIC) and a reanalysis product (MERRA-2), with methodology described in a peer-reviewed publication (Kramarova et al., 2021).
• Data is available from 2015 to the present, offering a multi-year time series for trend analysis.

Limitations

• Spatial resolution (1° x 1°) is coarser than the native EPIC total ozone product (18 km x 18 km).
• Metadata for row counts, file sizes, and specific column names is not provided across any source.
• The product relies on the accuracy of the MERRA-2 reanalysis for stratospheric ozone subtraction, which introduces a dependency on model data.

Provenance

Source

National Aeronautics and Space Administration (NASA), from the Deep Space Climate Observatory (DSCOVR) Earth Polychromatic Imaging Camera (EPIC).

Collection Method

Tropospheric ozone columns are derived by subtracting Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) stratospheric ozone fields from EPIC total ozone retrievals.

Time Range

2015-present

Freshness

Last updated on 2026-04-10 according to datagov metadata.

Geography

Global coverage of the sunlit portion of the Earth.