VIIRS/NPP Land Aerosol Optical Thickness L2G Daily Global 1km SIN Grid V002

The delivery of all Suomi National Polar-orbiting Partnership (Suomi NPP) VIIRS science data products will cease on November 2, 2026 (2026/306). Data users are encouraged to transition to the equivalent VJ219A1 (primary) or VJ119A1 (secondary) data products. The VNP19A1 Version 2 data product is a NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Bidirectional Reflectance Factor (BRF) gridded Level 2 product produced daily at 375 meter (m) and 750 m pixel resolution using the Rotated Sinusoidal (RSIN) projection. The VNP19A1 product is corrected for atmospheric gases and aerosols using a Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm that is based on a time series analysis and a combination of pixel- and image-based processing. The VIIRS MAIAC Land Surface BRF products provide an estimate of the surface spectral reflectance as it would be measured at ground-level in the absence of atmospheric scattering or absorption. Provided in the VNP19A1 product are layers for surface reflectance, cosines of solar and view zenith angles, relative azimuth, sun azimuth (SAZ), sensor view azimuth (VAZ), scattering angle and glint angle. Volumetric (Fv) and geometric-optics (Fg) kernels of the Ross-Thick Li-Sparse (RTLS) model for the observation geometry are also included. The 750 m surface reflectance layers are produced in cloud-free conditions from bands M1-M5, M7, M8, M10, and M11, whereas the 375 m layers are produced from bands I1-I3. Known Issues * The spatial resolution and projection of this product are listed incorrectly in the VNP19A1 long name. VNP19A1 uses the RSIN projection and is at 375 m and 750 m resolution. The long name should read “VIIRS/JPSS1 Land Surface BRF Daily L2G Global 375m and 750m RSIN Grid V002”. This will be rectified in future versions. * MAIAC Lookup Tables (LUTs) are built assuming pseudo-spherical correction in single scattering which has a reduced accuracy for high sun/view zenith angles. A reduced MAIAC performance is expected at solar zenith angles > 78°. * MAIAC may be missing bright salt pans in several world deserts. In such cases, it may generate a persistent high Aerosol Optical Depth (AOD) resulting in missing surface retrievals. * Because of inherent uncertainties of gridding on the coastline, the area of 1-3 pixels from the coastline may contain frequent artifacts in cloud mask (usually over-detection), AOD (higher values) and surface BRF. Users should exercise caution near the coastline as represented by the AOD QA bit 1010 (See Table 5.4 of the User Guide bits 8-11, 1010 -- AOD within +-2 km from the coastline is replaced by nearby AOD). * Atmospheric Correction (AC) over detected snow: as MAIAC does not retrieve AOD over snow, it assumes a low climatology AOD=0.05 globally and 0.02 at high elevations (H>4.2 km). Over north central China, which is often heavily polluted and low AOD assumption can lead to a significant bias, we use AOD averaged over mesoscale area of 150 km using reliable AOD retrievals over snow-free pixels. Such approach does improve quality of AC as compared to low-AOD assumption as judged by the reduced boundaries and color artifacts, but it does not account for the aerosol variability inside 150 km area. * Ice mask is currently unreliable. * Effective as of April 14, 2026, the processing of selected overlapping VIIRS MAIAC tiles within the forward stream has been discontinued to eliminate redundant data. A complete list of the excluded tiles can be found at VIIRS MAIAC Reduced Tiles.

The VJ119A2 Version 2 data product is a NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Land Aerosol Optical Depth (AOD) gridded Level 2 product produced daily at 750 meter (m) pixel resolution using the Rotated Sinusoidal (RSIN) projection. The VJ119A2 product provides the atmospheric properties and view geometry used to calculate the Multi-Angle Implementation of Atmospheric Correction (MAIAC) Land Surface Bidirectional Reflectance Factor (BRF) or surface reflectance, VJ119A1 product. Provided in the VJ119A2 product are layers for AOD, AOD uncertainty and QA, injection height of smoke plume, AOD outside of glint area, fine mode fraction, and cosines of solar and view zenith angles, relative azimuth, scattering angle, glint angle, and Angstrom Exponent over the ocean. Known Issues * The spatial resolution and projection of this product are listed incorrectly in the VJ119A2 long name. VJ119A2 uses the RSIN projection and is at 750 m resolution. The long name should read “VIIRS/JPSS1 Land Aerosol Optical Depth Daily L2G Global 750m RSIN Grid V002”. This will be rectified in future versions. * MAIAC Lookup Tables (LUTs) are built assuming pseudo-spherical correction in single scattering which has a reduced accuracy for high sun/view zenith angles. A reduced MAIAC performance is expected at solar zenith angles > 78°. * MAIAC may be missing bright salt pans in several world deserts. In such cases, it may generate a persistent high Aerosol Optical Depth (AOD) resulting in missing surface retrievals. * Because of inherent uncertainties of gridding on the coastline, the area of 1-3 pixels from the coastline may contain frequent artifacts in cloud mask (usually over-detection), AOD (higher values) and surface BRF. Users should exercise caution near the coastline as represented by the AOD QA bit 1010 (See Table 5.4 of the User Guide bits 8-11, 1010 -- AOD within +-2 km from the coastline is replaced by nearby AOD). * Atmospheric Correction (AC) over detected snow: as MAIAC does not retrieve AOD over snow, it assumes a low climatology AOD=0.05 globally and 0.02 at high elevations (H>4.2 km). Over north-central China, which is often heavily polluted and low AOD assumption can lead to a significant bias, we use AOD averaged over mesoscale area of 150 km using reliable AOD retrievals over snow-free pixels. Such approach does improve quality of AC as compared to low-AOD assumption as judged by the reduced boundaries and color artifacts, but it does not account for the aerosol variability inside 150 km area. * Ice mask is currently unreliable. * Effective as of April 14, 2026, the processing of selected overlapping VIIRS MAIAC tiles within the forward stream has been discontinued to eliminate redundant data. A complete list of the excluded tiles can be found at VIIRS MAIAC Reduced Tiles.

The VJ219A2 Version 2 data product is a NOAA-21 Visible Infrared Imaging Radiometer Suite (VIIRS) Land Aerosol Optical Depth (AOD) gridded Level 2 product produced daily at 750 meter (m) pixel resolution using the Rotated Sinusoidal (RSIN) projection. The VJ219A2 product provides the atmospheric properties and view geometry used to calculate the Multi-Angle Implementation of Atmospheric Correction (MAIAC) Land Surface Bidirectional Reflectance Factor (BRF) or surface reflectance, VJ219A1 product. Provided in the VJ219A2 product are layers for AOD, AOD uncertainty and QA, injection height of smoke plume, AOD outside of glint area, fine mode fraction, and cosines of solar and view zenith angles, relative azimuth, scattering angle, glint angle, and Angstrom Exponent over the ocean. Known Issues * MAIAC Lookup Tables (LUTs) are built assuming pseudo-spherical correction in single scattering which has a reduced accuracy for high sun/view zenith angles. A reduced MAIAC performance is expected at solar zenith angles > 78°. * MAIAC may be missing bright salt pans in several world deserts. In such cases, it may generate a persistent high Aerosol Optical Depth (AOD) resulting in missing surface retrievals. * Because of inherent uncertainties of gridding on the coastline, the area of 1-3 pixels from the coastline may contain frequent artifacts in cloud mask (usually over-detection), AOD (higher values) and surface BRF. Users should exercise caution near the coastline as represented by the AOD QA bit 1010 (See Table 5.4 of the User Guide bits 8-11, 1010 -- AOD within +-2 km from the coastline is replaced by nearby AOD). * Atmospheric Correction (AC) over detected snow: as MAIAC does not retrieve AOD over snow, it assumes a low climatology AOD=0.05 globally and 0.02 at high elevations (H>4.2 km). Over north-central China, which is often heavily polluted and low AOD assumption can lead to a significant bias, we use AOD averaged over mesoscale area of 150 km using reliable AOD retrievals over snow-free pixels. Such approach does improve quality of AC as compared to low-AOD assumption as judged by the reduced boundaries and color artifacts, but it does not account for the aerosol variability inside 150 km area. * Ice mask is currently unreliable. * Effective as of April 14, 2026, the processing of selected overlapping VIIRS MAIAC tiles within the forward stream has been discontinued to eliminate redundant data. A complete list of the excluded tiles can be found at VIIRS MAIAC Reduced Tiles.

The VJ119A1 Version 2 data product is a NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Bidirectional Reflectance Factor (BRF) gridded Level 2 product produced daily at 375 meter (m) and 750 m pixel resolutions using the Rotated Sinusoidal (RSIN) projection. The VJ119A1 product is corrected for atmospheric gases and aerosols using a Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm that is based on a time series analysis and a combination of pixel- and image-based processing. The VIIRS MAIAC Land Surface BRF products provide an estimate of the surface spectral reflectance as it would be measured at ground-level in the absence of atmospheric scattering or absorption. Provided in the VJ119A1 product are variables for surface reflectance, cosines of solar and view zenith angles, relative azimuth, sun azimuth (SAZ), sensor view azimuth (VAZ), scattering angle and glint angle. Volumetric (Fv) and geometric-optics (Fg) kernels of the Ross-Thick Li-Sparce (RTLS) model for the observation geometry are also included. The 750 m surface reflectance variables are produced in cloud-free conditions from bands M1-M5, M7, M8, M10, and M11, whereas the 375 m variables are produced from bands I1-I3. Known Issues * The spatial resolution and projection of this product are listed incorrectly in the VJ119A1 long name. VJ119A1 uses the RSIN projection and is at 375 m and 750 m resolution. The long name should read “VIIRS/JPSS1 Land Surface BRF Daily L2G Global 375m and 750m RSIN Grid V002”. This will be rectified in future versions. * MAIAC Lookup Tables (LUTs) are built assuming pseudo-spherical correction in single scattering which has a reduced accuracy for high sun/view zenith angles. A reduced MAIAC performance is expected at solar zenith angles > 78°. * MAIAC may be missing bright salt pans in several world deserts. In such cases, it may generate a persistent high Aerosol Optical Depth (AOD) resulting in missing surface retrievals. * Because of inherent uncertainties of gridding on the coastline, the area of 1-3 pixels from the coastline may contain frequent artifacts in cloud mask (usually over-detection), AOD (higher values) and surface BRF. Users should exercise caution near the coastline as represented by the AOD QA bit 1010 (See Table 5.4 of the User Guide bits 8-11, 1010 -- AOD within +-2 km from the coastline is replaced by nearby AOD). * Atmospheric Correction (AC) over detected snow: as MAIAC does not retrieve AOD over snow, it assumes a low climatology AOD=0.05 globally and 0.02 at high elevations (H>4.2 km). Over north central China, which is often heavily polluted and low AOD assumption can lead to a significant bias, we use AOD averaged over mesoscale area of 150 km using reliable AOD retrievals over snow-free pixels. Such approach does improve quality of AC as compared to low-AOD assumption as judged by the reduced boundaries and color artifacts, but it does not account for the aerosol variability inside 150 km area. * Ice mask is currently unreliable. * Effective as of April 14, 2026, the processing of selected overlapping VIIRS MAIAC tiles within the forward stream has been discontinued to eliminate redundant data. A complete list of the excluded tiles can be found at VIIRS MAIAC Reduced Tiles.

The VJ219A1 Version 2 data product is a NOAA-21 Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Bidirectional Reflectance Factor (BRF) gridded Level 2 product produced daily at 375 meter (m) and 750 m pixel resolutions using the Rotated Sinusoidal (RSIN) projection. The VJ219A1 product is corrected for atmospheric gases and aerosols using a Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm that is based on a time series analysis and a combination of pixel- and image-based processing. The VIIRS MAIAC Land Surface BRF products provide an estimate of the surface spectral reflectance as it would be measured at ground-level in the absence of atmospheric scattering or absorption. Provided in the VJ219A1 product are variables for surface reflectance, cosines of solar and view zenith angles, relative azimuth, sun azimuth (SAZ), sensor view azimuth (VAZ), scattering angle and glint angle. Volumetric (Fv) and geometric-optics (Fg) kernels of the Ross-Thick Li-Sparce (RTLS) model for the observation geometry are also included. The 750 m surface reflectance variables are produced in cloud-free conditions from bands M1-M5, M7, M8, M10, and M11, whereas the 375 m variables are produced from bands I1-I3. Known Issues * The spatial resolution and projection of this product are listed incorrectly in the VJ219A1 long name. VJ219A1 uses the RSIN projection and is at 375 m and 750 m resolution. References to 350 m are in error. The long name should read “VIIRS/JPSS2 Land Surface BRF Daily L2G Global 375m and 750m RSIN Grid V002”. This will be rectified in future versions. * MAIAC Lookup Tables (LUTs) are built assuming pseudo-spherical correction in single scattering which has a reduced accuracy for high sun/view zenith angles. A reduced MAIAC performance is expected at solar zenith angles > 78°. * MAIAC may be missing bright salt pans in several world deserts. In such cases, it may generate a persistent high Aerosol Optical Depth (AOD) resulting in missing surface retrievals. * Because of inherent uncertainties of gridding on the coastline, the area of 1-3 pixels from the coastline may contain frequent artifacts in cloud mask (usually over-detection), AOD (higher values) and surface BRF. Users should exercise caution near the coastline as represented by the AOD QA bit 1010 (See Table 5.4 of the User Guide bits 8-11, 1010 -- AOD within +-2 km from the coastline is replaced by nearby AOD). * Atmospheric Correction (AC) over detected snow: as MAIAC does not retrieve AOD over snow, it assumes a low climatology AOD=0.05 globally and 0.02 at high elevations (H>4.2 km). Over north central China, which is often heavily polluted and low AOD assumption can lead to a significant bias, we use AOD averaged over mesoscale area of 150 km using reliable AOD retrievals over snow-free pixels. Such approach does improve quality of AC as compared to low-AOD assumption as judged by the reduced boundaries and color artifacts, but it does not account for the aerosol variability inside 150 km area. * Ice mask is currently unreliable. * Effective as of April 14, 2026, the processing of selected overlapping VIIRS MAIAC tiles within the forward stream has been discontinued to eliminate redundant data. A complete list of the excluded tiles can be found at VIIRS MAIAC Reduced Tiles.

The VCD19A2CMG Version 2 data product is a combined NASA/NOAA Suomi National Polar-orbiting Partnership (Suomi NPP) and NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) Land Aerosol Optical Depth (AOD) and Water Vapor Level 3 product produced daily in a 0.05 degree (5,600 meters at the equator) Climate Modeling Grid (CMG). The VCD9A2CMG product is corrected for atmospheric gases and aerosols using a Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm that is based on a time series analysis and a combination of pixel- and image-based processing. The VCD19A2CMG AOD data product contains the variables for blue band AOD at 0.47 µm, green band AOD at 0.55 µm, AOD uncertainty, average cloud fraction, available AOD, satellite overpass times, line and sample number, offset, and number of AOD records. Known Issues * MAIAC Lookup Tables (LUTs) are built assuming pseudo-spherical correction in single scattering which has a reduced accuracy for high sun/view zenith angles. A reduced MAIAC performance is expected at solar zenith angles > 78°. * MAIAC may be missing bright salt pans in several world deserts. In such cases, it may generate a persistent high Aerosol Optical Depth (AOD) resulting in missing surface retrievals. * Because of inherent uncertainties of gridding on the coastline, the area of 1-3 pixels from the coastline may contain frequent artifacts in cloud mask (usually over-detection), AOD (higher values) and surface BRF. Users should exercise caution near the coastline as represented by the AOD QA bit 1010 (See Table 5.4 of the User Guide bits 8-11, 1010 -- AOD within +-2 km from the coastline is replaced by nearby AOD). * Atmospheric Correction (AC) over detected snow: as MAIAC does not retrieve AOD over snow, it assumes a low climatology AOD=0.05 globally and 0.02 at high elevations (H>4.2 km). Over north-central China, which is often heavily polluted and low AOD assumption can lead to a significant bias, we use AOD averaged over mesoscale area of 150 km using reliable AOD retrievals over snow-free pixels. Such approach does improve quality of AC as compared to low-AOD assumption as judged by the reduced boundaries and color artifacts, but it does not account for the aerosol variability inside 150 km area. * Ice Mask is currently unreliable.