OMVANC: Ancillary Geospatial Data for OMI/Aura Satellite Swaths

The OMVANC dataset provides selected GEOS-5 Forward Processing parameters co-located with the OMI/Aura VIS 1-Orbit L2 swath. It includes fields such as snow cover, sea ice cover, land cover, terrain height, a row anomaly flag, and pixel area to support atmospheric retrieval algorithms and related research. Data are provided in netCDF4 format, with each file approximately 45 MB in size and spatially aligned to the OMI UV-2 instrument's 13km x 24km nadir resolution.

Use Cases

• Masking snow-covered pixels in atmospheric trace gas retrievals based on the snow cover field.
• Identifying and filtering ocean pixels for sea surface studies using the sea ice cover field.
• Correcting for terrain effects in radiative transfer models based on the terrain height parameter.
• Flagging and excluding data affected by instrument row anomalies using the row anomaly flag.
• Calculating accurate radiance or reflectance per unit area using the provided pixel area data.

Strengths

• Data are specifically geo-colocated to the OMI/Aura swath, ensuring temporal and spatial alignment for direct use.
• Each data file is approximately 45 MB, indicating a consistent and manageable size for single-orbit analysis.
• The dataset provides key ancillary parameters (snow, ice, land cover, terrain) derived from the authoritative GEOS-5 FP-IT model.

Limitations

• Column names and a precise row count are not provided in the available metadata, limiting detailed schema understanding.
• The original GEOS-5 data is on a 0.625°x0.5° grid, which is regridded to the OMI footprint, potentially introducing interpolation artifacts.

Provenance

Source

Global Modeling and Assimilation Office (GMAO) GEOS-5 Forward Processing for Instrument Teams (FP-IT) product, processed by the OMI/Aura team.

Collection Method

Parameters are selected from the GEOS-5 FP-IT assimilated product and co-located in space and time with the OMI UV-2 swath.

Time Range

Coverage corresponds to the OMI/Aura mission lifetime for VIS 1.Orbit L2 swaths.

Freshness

2026-04-09 23:06:47.700651

Geography

Global coverage along the OMI/Aura satellite swath path.