The VIIRS/JPSS1 BRDF/Albedo Quality Daily L3 Global 500 m SIN Grid Near Real Time (NRT), short-name VJ143IA2N product provides BRDF and Albedo quality at 500 meter (m) resolution. The VJ143IA2N product is produced daily using 16-day VIIRS data (i.e., the current day and the previous 15 days to produce 16-day product).

The algorithm uses the RossThick/Li-Sparse-Reciprocal (RTLSR) semi-empirical kernel-driven BRDF model, with the three kernel weights from VJ143IA1N to reconstruct surface anisotropic effects, correcting the directional reflectance to a common view geometry (VJ143IA4N), while also computing integrated black-sky albedo (BSA) at local solar noon and white-sky albedo (WSA) (VJ143IA3N). Researchers can use the BRDF model parameters with a simple polynomial, to obtain black-sky albedo at any solar illumination angle. Likewise, both the BSA and WSA Science Dataset (SDS) layers can be used with a simple polynomial, to manually estimate instantaneous actual albedo (blue-sky albedo). Additional details regarding the methodology are available in the Algorithm Theoretical Basis Document (ATBD) at https://www.umb.edu/editor_uploads/images/school_for_the_environment_cs/Viirs/VIIRS_ATBD_Apr_Jul2017.pdf.

The VJ143IA2N data product provides a total of 11 SDS layers including: BRDF/Albedo band quality (inversion information) and days of valid observation within a 16-day period for VIIRS imagery bands I1, I2, and I3, as well as land water type class flag, snow BRDF albedo class flag, local solar noon, and the platform name.