VNP43D81: VIIRS Nadir BRDF-Adjusted Reflectance for Band M2

Daily VNP43D81 data provides Nadir BRDF-Adjusted Reflectance (NBAR) for the VIIRS band M2 at 0.445 μm. It is produced using a 16-day temporal window at a 30 arc second (1,000 meter) resolution on a global Climate Modeling Grid. The NBAR algorithm removes view angle effects to model reflectance as if collected from a nadir view at local solar noon.

Use Cases

• Climate simulation modeling based on the global Climate Modeling Grid (CMG) coverage.
• Analyzing surface anisotropy and albedo using the Bidirectional Reflectance Distribution Function (BRDF) methodology.
• Monitoring land surface reflectance changes over time using the daily, temporally-weighted product.
• Cross-comparing reflectance across VIIRS moderate resolution bands (M1-M5, M7, M8, M10, M11) and the Day/Night Band (DNB).

Strengths

• Provides global coverage on a Climate Modeling Grid suitable for climate models.
• Offers daily data with a consistent 30 arc second spatial resolution.
• Applies a standardized NBAR algorithm to correct for view angle effects.

Limitations

• The VNP43D81 Version 1 product was decommissioned on July 31, 2025, indicating it is obsolete.
• Known issues exist, such as reduced input observations due to high aerosol flag activation in upstream Collection 1 products.
• Each file contains only one data layer due to large file sizes, limiting immediate multi-band analysis.

Provenance

Source

NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS)

Collection Method

Produced daily using 16 days of data, temporally weighted to the ninth day.

Freshness

Last updated metadata dates are 2026-04-09 and 2025-02-01, but the core data product is decommissioned.

Geography

Global