OMCLDO2G: Daily Global Cloud Pressure and Fraction from OMI

OMI/Aura satellite data provides daily global cloud measurements by analyzing the O2-O2 absorption band at 477 nm using Differential Optical Absorption Spectroscopy (DOAS). The OMCLDO2G product bins high-resolution pixel-level data into 0.25x0.25 degree grids without averaging, allowing scientists to apply custom filtering schemes. Each daily file, covering roughly 14 sunlit orbits, is approximately 85 MB and stored in HDF-EOS5 format.

Use Cases

• Validating climate and weather model cloud parameterizations based on cloud pressure and fraction data.
• Studying cloud-aerosol interactions using co-located cloud fraction and slant column ozone information.
• Analyzing global cloud top pressure distribution for radiative transfer calculations.
• Creating custom gridded climate data products by applying user-defined filters to the raw binned pixels.

Strengths

• Provides a high-resolution global grid at 0.25x0.25 degrees, derived from pixel-level satellite observations.
• Includes detailed ancillary data such as solar and satellite viewing angles, terrain information, and quality flags for rigorous analysis.
• Data is saved 'Without Averaging' in the grid, preserving original pixel values for flexible user reprocessing.

Limitations

• Metadata completeness is low; specific column names, row counts, and exact temporal coverage are not provided in the sources.
• The listed last update date of 2026-04-09 appears to be a future date, which may indicate a metadata error or placeholder.
• Documentation gaps exist regarding the specific 'other-license-specified' and its terms of use.

Provenance

Source

National Aeronautics and Space Administration (NASA), with product lead scientist Dr. Pepijn Veefkind from KNMI.

Collection Method

Spectral fitting of the O2-O2 absorption band from the Ozone Monitoring Instrument (OMI) on the Aura satellite, using the DOAS technique.

Freshness

2026-04-09 23:18:27.610258

Geography

Global coverage, gridded.