Level 1 twilight radiance files provide radiance measured during twilight hours to capture city lights at TEMPO’s native spatial resolution, ~10 km^2 at the center of the Field of Regard (FOR), for individual granules. Each granule covers the entire North-South TEMPO FOR but only a portion of the East-West FOR. The files are provided in netCDF4 format, and contain information on radiometrically calibrated and geolocated radiances for the UV and visible bands, corresponding noise, geolocation, viewing geometry, quality flags and other ancillary information. The product is produced using the L0-1b processor which includes image processing steps to produce radiometrically calibrated radiances with nominal navigation. These data reached provisional validation on December 9, 2024.

Level 1 radiance files provide radiance information at TEMPO’s native spatial resolution, ~10 km^2 at the center of the Field of Regard (FOR), for individual granules. Each granule covers the entire North-South TEMPO FOR but only a portion of the East-West FOR. The files are provided in netCDF4 format, and contain information on radiometrically and wavelength calibrated and geolocated radiances for the UV and visible bands, corresponding noise, parameterized wavelength grid, geolocation, viewing geometry, quality flags and other ancillary information. The product is produced using the L0-1b processor which includes multiple steps: (1) Image processing to produce radiometrically calibrated radiance, (2) Additional wavelength calibration to improve wavelength registration, (3) Image Navigation and Registration (INR) using GOES-R data, and (4) post INR processing geolocation tagging. These data reached provisional validation on December 9, 2024.

Level 1 radiance files provide radiance information at TEMPO’s native spatial resolution, ~10 km^2 at the center of the Field of Regard (FOR), for individual granules. Each granule covers the entire North-South TEMPO FOR but only a portion of the East-West FOR. The files are provided in netCDF4 format, and contain information on radiometrically and wavelength calibrated and geolocated radiances for the UV and visible bands, corresponding noise, parameterized wavelength grid, geolocation, viewing geometry, quality flags and other ancillary information. The product is produced using the L0-1b processor which includes multiple steps: (1) Image processing to produce radiometrically calibrated radiance, (2) Additional wavelength calibration to improve wavelength registration, (3) Image Navigation and Registration (INR) using GOES-R data, and (4) post INR processing geolocation tagging. These data reached provisional validation on December 9, 2024.

The Visible Infrared Imaging Radiometer Suite (VIIRS) Moderate Resolution Terrain Correction Geolocation (VNP03MODLL) Version 2 product from the NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) VIIRS sensor is produced in 6 minute temporal satellite increments (swaths) at 750 meter resolution. Intersecting the VIIRS line of sight vector with Earth’s geoid and the World Geodetic System (WGS) ellipsoid, this product is based on the SRTM30 Version 2 digital elevation model (DEM), which uses GTOPO30 data for areas from 60° North to 60° South. VNP03MODLL is a terrain correction geolocation product that provides the spatial location for various VIIRS data products. Each swath of data is approximately 3,060 kilometers along track (long) and 3,060 kilometers across track (wide). Provided in the VNP03MODLL product are layers for height, latitude, and longitude. These Science Data Sets (SDS) layers / Variables are used in conjunction with the [VNP14](https://doi.org/10.5067/viirs/vnp14.002) swath product for accurate geolocation information.Known Issues* For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=VIIRS).Improvements/Changes from Previous Versions* Improved calibration algorithm and better coefficients for entire Suomi NPP mission.* Improved geolocation accuracy and updates to fix outliers around maneuver periods and other events.* Corrections to the aerosol quantity flag (low, average, high) mainly over brighter surfaces in the mid to high latitudes such as desert and tropical vegetation areas. This has an impact on the retrieval of other downstream data products such as VNP13 Vegetation Indices and VNP43 BRDF/Albedo.* Improved cloud mask input product for corrections along coastlines and artifacts from use of coarse resolution climatology data.* Replaced the land/water mask input product with MODIS heritage seven class land/water mask.* More details can be found in this [VIIRS Land V2 Changes document](https://landweb.modaps.eosdis.nasa.gov/data/userguide/VIIRS_Land_C2_Changes_09152022.pdf).

The VNP03IMG, a Near Real Time (NRT) product, includes the geolocation fields that are calculated for each VIIRS imagery resolution band (I-band) Line of sight (LOS) for all orbits at the nominal resolution of 375 m. The locations and ancillary information correspond to the intersection of the centers of each Field of View (FOV) from 32 detectors in an ideal I-band on the Earth's surface. A digital terrain model is used to model the Earth's surface. The main inputs are the spacecraft attitude and orbit ephemeris data, the instrument telemetry and the digital elevation model. The geolocation fields contained within the VNP03IMG Geolocation files include geodetic latitude, longitude, surface height above the geoid, solar zenith and azimuth angles, satellite zenith and azimuth angles, and a land/water mask for each 375m sample. Additional information is included in the header to enable the calculation of the approximate location of the center of the detectors for any of the VIIRS bands. This product is used as input by a large number of subsequent VIIRS Imagery Resolution products, particularly those produced by the Land team.file_naming_convention = VNP03IMG_NRT.AYYYYDDD.HHMM.CCC.nc AYYYYDDD = Acquisition Year and Day of Year HHMM = Hour and minute of acquisition CCC = Collection number nc = NetCDF5

The VNP03MOD_NRT, a Near Real Time (NRT) product, includes the geolocation fields that are calculated for each VIIRS moderate resolution band (M-band) Line of sight (LOS) for all orbits at the nominal resolution of 750 m. The locations and ancillary information correspond to the intersection of the centers of each Field of View (FOV) from 16 detectors in an ideal M-band on the Earth's surface. A digital terrain model is used to model the Earth's surface. The main inputs are the spacecraft attitude and orbit ephemeris data, the instrument telemetry and the digital elevation model. The geolocation fields contained within the VNP03MOD Geolocation files include geodetic latitude, longitude, surface height above the geoid, solar zenith and azimuth angles, satellite zenith and azimuth angles, and a land/water mask for each 750m sample. Additional information is included in the header to enable the calculation of the approximate location of the center of the detectors for any of the VIIRS bands. This product is used as input by subsequent VIIRS Moderate Resolution products, particularly those produced by the Land team.file_naming_convention = VNP03MOD_NRT.AYYYYDDD.HHMM.CCC.nc AYYYYDDD = Acquisition Year and Day of Year HHMM = Hour and minute of acquisition CCC = Collection number nc = NetCDF5

The Visible Infrared Imaging Radiometer Suite (VIIRS) (https://lpdaac.usgs.gov/dataset_discovery/viirs) Moderate Resolution Terrain Correction Geolocation (VJ103MODLL) Version 2.1 product from the NOAA-20 VIIRS sensor is produced in 6 minute temporal satellite increments (swaths) at 750 meter resolution. Intersecting the VIIRS line of sight vector with Earth’s geoid and the World Geodetic System (WGS) ellipsoid, this product is based on the SRTM30 Version 2 digital elevation model (DEM), which uses GTOPO30 data for areas from 60° North to 60° South. VJ103MODLL is a terrain correction geolocation product that provides the spatial location for various VIIRS data products. Each swath of data is approximately 3,060 kilometers along track (long) and 3,060 kilometers across track (wide). Provided in the VJ103MODLL product are layers for height, latitude, and longitude. These Science Data Sets (SDS) layers are used in conjunction with the (VJ114) (https://doi.org/10.5067/viirs/vj114.002) swath product for accurate geolocation information.

The Visible Infrared Imaging Radiometer Suite (VIIRS) Moderate Resolution Terrain Correction Geolocation (VJ103MODLL) Version 2.1 product from the NOAA-20 VIIRS sensor is produced in 6 minute temporal satellite increments (swaths) at 750 meter resolution. Intersecting the VIIRS line of sight vector with Earth’s geoid and the World Geodetic System (WGS) ellipsoid, this product is based on the SRTM30 Version 2 digital elevation model (DEM), which uses GTOPO30 data for areas from 60° North to 60° South. VJ103MODLL is a terrain correction geolocation product that provides the spatial location for various VIIRS data products. Each swath of data is approximately 3,060 kilometers along track (long) and 3,060 kilometers across track (wide). Provided in the VJ103MODLL product are layers for height, latitude, and longitude. These Science Data Sets (SDS) layers are used in conjunction with the ([VJ114](https://doi.org/10.5067/viirs/vj114.002)) swath product for accurate geolocation information.Known Issues* For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=VIIRS).Improvements/Changes from Previous VersionThe NOAA-20 VIIRS algorithms include the same improvements as the S-NPP VIIRS V002.* Improved calibration algorithm and better coefficients for entire NOAA-20 mission.* Improved geolocation accuracy and updates to fix outliers around maneuver periods and other events.* Corrections to the aerosol quantity flag (low, average, high) mainly over brighter surfaces in the mid to high latitudes such as desert and tropical vegetation areas. This has an impact on the retrieval of other downstream data products such as VJ113 Vegetation Indices and VJ143 BRDF/Albedo.* Improved cloud mask input product for corrections along coastlines and artifacts from use of coarse resolution climatology data.* Replaced the land/water mask input product with MODIS heritage seven class land/water mask.* More details can be found in this [VIIRS Land V2 Changes document](https://landweb.modaps.eosdis.nasa.gov/data/userguide/VIIRS_Land_C2_Changes_09152022.pdf)

The VNP03DNB_NRT,a Near Real Time (NRT) product, includes the geolocation fields that are calculated for VIIRS day-night band (DNB) Line of sight (LOS) for all orbits at the nominal resolution of 750 m. The locations and ancillary information correspond to the intersection of the centers of each Field of View (FOV) from 16 detectors in the DNB on the Earth's surface. A digital terrain model is used to model the Earth's surface. The main inputs are the spacecraft attitude and orbit ephemeris data, the instrument telemetry and the digital elevation model. The geolocation fields contained within the VNP03DNB Geolocation files include geodetic latitude, longitude, surface height above the geoid, solar and lunar zenith and azimuth angles, lunar phase angle and illumination fraction, satellite zenith and azimuth angles, and a land/water mask for each 750m sample. Additional information is included in the header to enable the calculation of the approximate location of the center of the detectors for any of the VIIRS bands. This product is used as input by subsequent VIIRS day/night band products, particularly those produced by the Land team.file_naming_convention = "VNP03DNB_NRT.AYYYYDDD.HHMM.CCC.nc AYYYYDDD = Acquisition Year and Day of Year HHMM = Hour and minute of acquisition CCC = Collection number nc = NetCDF5