VIIRS/NPP Downward Shortwave Radiation Daily L3 Global 1km SIN Grid V002

The VNP18A1 Version 2 is a NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Downward Shortwave Radiation (DSR) gridded Level 3 product. It is produced at 1 kilometer pixel resolution at daily intervals. DSR is the incident solar radiation over land surfaces in the shortwave spectrum (300-4,000 nanometers) and is a significant variable in land surface models (LSMs), receiving increased attention due to its importance for the management and operation of solar energy systems.

The VNP18 algorithm adapts the narrowband look-up table (LUT) approach to estimate DSR. The LUTs consider different types of loadings of aerosols and clouds at a variety of illumination and viewing geometry. The Algorithm Theoretical Basis Document (ATBD) is forthcoming and will provide additional details regarding the methodology used to create the data.

Provided in the VNP18A1 product are variables for instantaneous total, direct, and diffuse DSR, as well as 3-hour DSR, daily mean DSR, and a quality variable.