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Description

The Visible Infrared Imaging Radiometer Suite (VIIRS) daily surface reflectance Climate Modeling Grid (VJ109CMG) 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) and nine moderate resolution bands (M1-M5, M7, M8, M10, M11) at 0.05 degree (~5,600 meter) resolution. 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. This product uses a weighted average of the best quality observation and is formatted as a CMG for use in climate simulation models. This product includes the twelve reflectance bands, five moderate resolution brightness temperature bands (M12-M16) and information layers representing relative azimuth angle, sensor zenith angle, solar zenith angle, reflectance band quality, time of day, and number mapping.

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
5600 Meters x 5600 Meters
Geographic Region
GLOBAL
Coordinate System
CARTESIAN
Granule Spatial Representation
CARTESIAN
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
C2519121257-LPCLOUD
Data State
ACTIVE
Processing Level
3
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 L3 Global 0.05 Deg CMG V002 [Data set]. NASA Land Processes Distributed Active Archive Center. https://doi.org/10.5067/VIIRS/VJ109CMG.002 Date Accessed: 2025-10-21

File Naming Convention

VJ109CMG.A2025222.002.2025223104825.h5

The file name begins with the Product Short Name (VJ109CMG) followed by the Julian Date of Acquisition formatted as AYYYYDDD (A2025222), the Version of the data collection (002), the Julian Date and Time of Production designated as YYYYDDDHHMMSS (2025223104825), 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
BrightTemp_M12 Brightness Temperature CMG Band M12 Kelvin uint16 0 0 to 40000 0.01
BrightTemp_M13 Brightness Temperature CMG Band M13 Kelvin uint16 0 0 to 40000 0.01
BrightTemp_M14 Brightness Temperature CMG Band M14 Kelvin uint16 0 0 to 40000 0.01
BrightTemp_M15 Brightness Temperature CMG Band M15 Kelvin uint16 0 0 to 40000 0.01
BrightTemp_M16 Brightness Temperature CMG Band M16 Kelvin uint16 0 0 to 40000 0.01
Granule_Time Granule Time Hours int16 0 0 to 2355 1
NPix_375m_Averaged Number 375 m pixels averaged N/A uint16 0 0 to 800 N/A
NPix_750m_Averaged Number 750 m pixels averaged N/A uint16 0 0 to 200 N/A
Number_Mapping_1 Number Mapping 1 Adjacent cloud/snow N/A uint32 0 0 to 14000000 N/A
Number_Mapping_2 Number Mapping 2 cloud/cloud shadow N/A uint32 0 0 to 14000000 N/A
RelativeAzimuth Relative azimuth angle Degree int16 0 0 to 18000 0.01
SensorZenith Sensor zenith angle Degree int16 0 0 to 18000 0.01
SolarZenith Solar zenith angle Degree int16 0 0 to 18000 0.01
State_QA CMG State Quality Assurance (QA) flags Bit Field int16 0 0 to 65535 N/A
SurfReflect_I1 Surface Reflectance CMG Band I1 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_I2 Surface Reflectance CMG Band I2 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_I3 Surface Reflectance CMG Band I3 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M1 Surface Reflectance CMG Band M1 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M2 Surface Reflectance CMG Band M2 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M3 Surface Reflectance CMG Band M3 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M4 Surface Reflectance CMG Band M4 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M5 Surface Reflectance CMG Band M5 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M7 Surface Reflectance CMG Band M7 N/A uint16 -28672 -28672 to 16000 0.0001
SurfReflect_M8 Surface Reflectance CMG Band M8 N/A uint16 -28672 -28672 to 16000 0.0001
SurfReflect_M10 Surface Reflectance CMG Band M10 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_M11 Surface Reflectance CMG Band M11 N/A int16 -28672 -28672 to 16000 0.0001
SurfReflect_QF1 Quality Flag 1 Bit Field uint8 255 255 to 254 N/A
SurfReflect_QF2 Quality Flag 2 Bit Field uint8 255 255 to 254 N/A
SurfReflect_QF3 Quality Flag 3 Bit Field uint8 255 255 to 254 N/A
SurfReflect_QF4 Quality Flag 4 Bit Field uint8 255 255 to 254 N/A
SurfReflect_QF5 Quality Flag 5 Bit Field uint8 255 255 to 254 N/A
SurfReflect_QF6 Quality Flag 6 Bit Field uint8 255 255 to 254 N/A
SurfReflect_QF7 Quality Flag 7 BitField uint8 255 255 to 254 N/A
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