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Description

The 8-day Visible Infrared Imaging Radiometer Suite (VIIRS) surface reflectance (VNP09A1) Version 2 composite product provides an estimate of land surface reflectance from the NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) VIIRS sensor for nine moderate resolution bands (M1 - M5, M7, M8, M10, M11) at nominal 1 kilometer resolution (~926 meter). The 1 kiliometer dataset is derived through resampling the native 750 meter VIIRS resolution in the Level 2 input product. The data are corrected for atmospheric conditions such as the effects of molecular gases, including ozone and water vapor, and for the effects of atmospheric aerosols. Each pixel represents the best possible Level 2G observation during an 8-day period that is selected on the basis of high observation coverage, low sensor angle, the absence of clouds or cloud shadow, and aerosol loading.

Included in the product along with the nine reflectance bands are day of year, reflectance band quality, control, reflectance state quality assurance, relative azimuth angle, sensor zenith angle, and solar zenith angle layers.

Known Issues

Improvements/Changes from Previous Versions

  • Improved calibration algorithm and coefficients for entire Suomi NPP 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.

Product Summary

Platforms
Suomi-NPP
Instruments
VIIRS
Spatial Extent
N: 90 S: -90 E: 180 W: -180
Spatial Resolution
1000 Meters x 1000 Meters
Geographic Region
GLOBAL
Coordinate System
CARTESIAN
Granule Spatial Representation
GEODETIC
Temporal Extent
2012-01-01 to Present
Temporal Resolution
8 Day
Data Partner
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)
Land Processes Distributed Active Archive Center (LP DAAC)
Concept ID
c2519124793-lpcloud
Data State
ACTIVE
Processing Level
3
Published
Updated

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/NPP Surface Reflectance 8-Day L3 Global 1km SIN Grid V002 [Data set]. NASA Land Processes Distributed Active Archive Center. https://doi.org/10.5067/VIIRS/VNP09A1.002 Date Accessed: 2025-07-17

Documents

ALGORITHM THEORETICAL BASIS DOCUMENT (ATBD) The ATBD provides physical theory and mathematical procedures for the calculations used to produce the data products.
PRODUCT QUALITY ASSESSMENT The LDOPE Land Product Quality Assessment website provides known issues, maneuvers, and product quality of the land products.
SCIENCE DATA PRODUCT VALIDATION Validation at stage 3 has been achieved for the VIIRS surface reflectance product suite.
SCIENCE DATA PRODUCT VALIDATION Further details regarding VIIRS product validation and maturity status are available from VIIRS Land Product Quality Assessment site.
USER'S GUIDE The technical information in the Version 2.0 User's Guide enables users to interpret and use the data products.

Learning Resources

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