OMCLDO2Z: Cloud Pressure and Fraction from Aura Satellite

NASA's OMI/Aura Cloud Pressure and Fraction (O2-O2 Absorption) Zoomed dataset provides Level-2 cloud data at a 13x12 km nadir resolution. It contains effective cloud pressure, effective cloud fraction, and slant column O2-O2 derived from spectral fitting of the O2-O2 absorption band at 477 nm using the DOAS technique. The product includes uncertainties, geolocation, viewing angles, and quality flags, with one file generated per month from zoomed radiance observations.

Use Cases

• Analyzing cloud fraction variability for climate model validation based on the effective cloud fraction parameter.
• Studying cloud-top pressure distribution to understand atmospheric dynamics based on the effective cloud pressure parameter.
• Validating other satellite cloud retrievals using the high-resolution (13x12 km) geolocated pixel data.
• Investigating the O2-O2 absorption method's performance for cloud detection based on the slant column O2-O2 data.
• Assessing data quality for specific regions or times using the included quality flags and uncertainty parameters.

Strengths

• Provides high-resolution cloud data at 13x12 km pixel scale at nadir.
• Based on a specific, documented algorithm (O2-O2 absorption using DOAS technique).
• Data is hosted and maintained by NASA's GES DISC, a recognized authoritative source.
• Cross-platform presence on datagov and nasa_earthdata signals importance and accessibility.

Limitations

• Sparse column metadata; specific data fields must be inferred from the description.
• Data collection is limited to one file per month, offering lower temporal resolution than daily products.
• The reprocessing date (late 2011) suggests the algorithm version may not reflect the most recent methods.

Provenance

Source

National Aeronautics and Space Administration (NASA), Goddard Earth Sciences Data and Information Services Center (GES DISC)

Collection Method

Satellite remote sensing via the Aura Ozone Monitoring Instrument (OMI), using the O2-O2 absorption DOAS technique.

Freshness

2026-04-09 (metadata update on datagov)

Geography

Global coverage from satellite orbits.