VNP43IA1: VIIRS/NPP BRDF Model Parameters Daily Global 500m Grid

500-meter resolution kernel weights from the Suomi NPP VIIRS sensor are provided daily, using a 16-day data window weighted to the ninth day. The dataset contains three spectrally dependent model parameters—isotropic (fiso), volumetric (fvol), and geometric (fgeo)—based on the RossThick/Li-Sparse-Reciprocal BRDF model. These parameters are designed to model surface anisotropic effects and support the continuity of NASA's MODIS BRDF/Albedo product suite.

Use Cases

• Correcting directional reflectance to a common view geometry using the provided BRDF model parameters.
• Estimating black-sky albedo at any solar illumination angle by applying a polynomial to the kernel weights.
• Manually calculating instantaneous actual (blue-sky) albedo using the integrated black-sky and white-sky albedo layers.
• Studying land surface anisotropy and radiative properties for climate and energy balance studies.

Strengths

• Provides a specific, high spatial resolution of 500 meters.
• Employs a documented, semi-empirical kernel-driven model (RTLSR) for BRDF correction.
• Designed for continuity with the established MODIS BRDF/Albedo data product suite.

Limitations

• The Version 1 product was explicitly decommissioned on July 31, 2025, limiting its use for current analysis.
• Key metadata such as row count, file size, and specific column names are unavailable across all sources.
• Platforms list conflicting 'last updated' dates (2026-04-09 and 2025-02-08), creating uncertainty about provenance.

Provenance

Source

NASA/NOAA Suomi NPP satellite, Visible Infrared Imaging Radiometer Suite (VIIRS) sensor, processed by LPCLOUD.

Collection Method

Daily production using a temporally weighted composite of 16 days of VIIRS data.

Time Range

Daily coverage, but the specific date range of available files is not provided.

Freshness

2026-04-09 20:43:40.221400

Geography

Global coverage on a 500m Sinusoidal (SIN) grid.