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Description

The Visible Infrared Imaging Radiometer Suite (VIIRS) daily surface reflectance (VJ109GA) Version 2 product provides an estimate of land surface reflectance from the NOAA-20 VIIRS sensor. Data are provided for three imagery bands (I1-I3) at nominal 500 meter resolution (~463 meter) and nine moderate resolution bands (M1-M5, M7, M8, M10, M11) at nominal 1 kilometer (~926 meter) resolution. The 500 meter and 1 kilometer datasets are derived through resampling the native 375 meter and 750 meter VIIRS resolutions, respectively, in the Level 2 input product. These bands are corrected for atmospheric conditions such as the effects of molecular gases, including ozone and water vapor, and for the effects of atmospheric aerosols.

The inputs to the surface reflectance algorithm are top-of-atmosphere reflectance for the VIIRS visible bands, the VIIRS cloud mask and aerosol product, aerosol optical thickness and atmospheric data obtained from the NOAA National Centers for Environmental Prediction (NCEP) reanalysis system. Along with the twelve reflectance bands are reflectance band quality, sensor azimuth angle, solar azimuth angle, sensor zenith angle, solar zenith angle, and observations layers. The reflectance layers from the VJ109GA data product are used as input data for many of the VIIRS land products.

Known Issues

Improvements/Changes from Previous Version

  • Improved calibration algorithm and coefficients for entire NOAA-20 mission.
  • Improved geolocation accuracy and applied updates to fix outliers around maneuver periods.
  • Corrected 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 Bidirectional Reflectance Distribution Function (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 the eight-class land/water mask from the VNP03 geolocation product that better aligns with MODIS.
  • Added secondary day-night flag to improve retrieval of Climate Modeling Grid (CMG) values over daytime pixels.
  • More details can be found in this VIIRS Land V2 Changes document.

Version Description

Collection Version 2 Processing and Reprocessing

Product Summary

Platforms
NOAA-20
Instruments
VIIRS
Spatial Extent
N: 90 S: -90 E: 180 W: -180
Spatial Resolution
500 Meters x 500 Meters
1000 Meters x 1000 Meters
Geographic Region
GLOBAL
Coordinate System
CARTESIAN
Granule Spatial Representation
GEODETIC
Temporal Extent
2018-01-01 to Present
Temporal Resolution
1 Day
Data Partner
Land Processes Distributed Active Archive Center (LP DAAC)
Land Science Investigator-led Processing System, Terrestrial Information Systems Laboratory, Earth Sciences Division, Sciences and Exploration Directorate, Goddard Space Flight Center, NASA (NASA/GSFC/SED/ESD/TISL/LandSIPS)
Concept ID
C2631841524-LPCLOUD
Data State
ACTIVE
Processing Level
2G
Published
Updated
Science Keywords
Reflectance

Citation

Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.

Copy Citation

Vermote, E., Franch, B., & Claverie, M. (2023). VIIRS/JPSS1 Surface Reflectance Daily L2G Global 1km and 500m SIN Grid V002 [Data set]. NASA Land Processes Distributed Active Archive Center. https://doi.org/10.5067/VIIRS/VJ109GA.002 Date Accessed: 2025-11-01

File Naming Convention

VJ109GA.A2025222.h03v05.002.2025223065217.h5

The file name begins with the Product Short Name (VJ109GA) followed by the Julian Date of Acquisition formatted as AYYYYDDD (A2025222), the Tile Identifier which is horizontal tile and vertical tile provided as hXXvYY (h03v05), the Version of the data collection (002), the Julian Date and Time of Production designated as YYYYDDDHHMMSS (2025223065217), and the Data Format (h5).

Documents

Variables

Variables are a set of physical properties whose values determine the characteristics or behavior of something. For example, temperature and pressure are variables of the atmosphere. Parameters and variables can be used interchangeably. Variable level attributes provide individual information for each variable.

The Name in this table is the variable name. Fill value indicates missing or undefined data points in a variable. Valid range is the range of values the variable can store. Scale factor is used to increase or decrease the size of an object and can be used to correct for distortion. For questions on a specific variable, please use the Earthdata Forum.

Name Description Units Data Type Fill Value Valid Range Scale Factor
iobs_res_1 Observation Number in Coarser Grid N/A uint8 255 255 to 254 N/A
land_water_mask_1 Moderate (750m) Land Water Mask Bit Field uint8 255 255 to 7 N/A
num_observations_1km Number of additional observations per row N/A int32 -1 -1 to 2147483647 N/A
num_observations_500m Number of additional observations per row N/A int32 -1 -1 to 2147483647 N/A
obscov_1km_1 Observations coverage 1 km Percent int8 -1 -1 to 100 0.01
obscov_500m_1 Observation coverage 500 m Percent int8 -1 -1 to 100 0.01
orbit_pnt_1 Orbit Pointer N/A int8 -1 -1 to 15 N/A
SensorAzimuth_1 Sensor Azimuth Angle Degree int16 -32768 -32768 to 18000 0.01
SensorZenith_1 Sensor Zenith Angle Degree int16 -32768 -32768 to 18000 0.01
SolarAzimuth_1 Solar Azimuth Angle Degree int16 -32768 -32768 to 18000 0.01
SolarZenith_1 Solar Zenith Angle Degree int16 -32768 -32768 to 18000 0.01
SurfReflect_I1_1 Imagery (375m) Surface Reflectance Band 1 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_I2_1 Imagery (375m) Surface Reflectance Band 2 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_I3_1 Imagery (375m) Surface Reflectance Band 3 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M1_1 Moderate (750m) Surface Reflectance Band 1 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M2_1 Moderate (750m) Surface Reflectance Band 2 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M3_1 Moderate (750m) Surface Reflectance Band 3 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M4_1 Moderate (750m) Surface Reflectance Band 4 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M5_1 Moderate (750m) Surface Reflectance Band 5 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M7_1 Moderate (750m) Surface Reflectance Band 7 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M8_1 Moderate (750m) Surface Reflectance Band 8 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M10_1 Moderate (750m) Surface Reflectance Band 10 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M11_1 Moderate (750m) Surface Reflectance Band 11 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_QF1_1 Moderate (750m) Land Quality Flags Byte 1 Bit Field uint8 N/A N/A to 255 N/A
SurfReflect_QF2_1 Moderate (750m) Land Quality Flags Byte 2 Bit Field uint8 N/A N/A to 255 N/A
SurfReflect_QF3_1 Moderate (750m) Land Quality Flags Byte 3 Bit Field uint8 N/A N/A to 255 N/A
SurfReflect_QF4_1 Moderate (750m) Land Quality Flags Byte 4 Bit Field uint8 N/A N/A to 255 N/A
SurfReflect_QF5_1 Moderate (750m) Land Quality Flags Byte 5 Bit Field uint8 N/A N/A to 255 N/A
SurfReflect_QF6_1 Moderate (750m) Land Quality Flags Byte 6 Bit Field uint8 N/A N/A to 255 N/A
SurfReflect_QF7_1 Moderate (750m) Land Quality Flags Byte 7 Bit Field uint8 N/A N/A to 255 N/A
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