VIIRS/NOAA20: Aerosol Optical Depth from Dark Target Algorithm

NASA's VIIRS/NOAA20 Dark Target Aerosol L2 product provides satellite-derived measurements of Aerosol Optical Thickness (AOT) over land and ocean. The dataset, part of the NASA MEaSUREs GEO-LEO project, uses a 6-km at-nadir resolution algorithm and is produced at a 6-minute cadence. It contains 45 Science Data Set layers, including geolocation and geophysical parameters, and spans from January 2019 through December 2022.

Use Cases

• Monitoring regional air pollution plumes based on Aerosol Optical Depth (AOD) retrievals.
• Studying aerosol-climate interactions using spectral AOT and particle size parameters over oceans.
• Validating and calibrating aerosol models with consistent data from multiple satellite sensor platforms.
• Analyzing diurnal aerosol patterns from the 6-minute cadence swath data.

Strengths

• Provides a consistent aerosol product across seven sensor/platform combinations as part of a NASA MEaSUREs project.
• Offers high temporal granularity with data granules produced approximately every 6 minutes.
• Contains 45 structured Science Data Set layers for detailed geophysical analysis.

Limitations

• Spatial resolution degrades away from nadir due to sensor scanning geometry.
• Metadata completeness is inconsistent across platforms, with conflicts in last updated dates (2023-01-01 vs. 2026-04-09).
• Column names and exact data volume (row count, file size) are not specified in the provided sources.

Provenance

Source

NASA LAADS (Level-1 and Atmosphere Archive & Distribution System), Dark Target aerosol team led by Robert Levy.

Collection Method

Satellite remote sensing via the NOAA-20 spacecraft's Visible Infrared Imaging Radiometer Suite (VIIRS), processed with the MODIS Dark Target aerosol retrieval algorithm.

Time Range

January 2019 - December 2022

Freshness

2026-04-09 20:45:10.153369

Geography

Global