NOAA Center for Satellite Applications and Research banner
 
National Oceanic & Atmospheric Administration website NOAA Center for Satellite Applications and Research website

STAR / SMCD / VIIRS Aerosol Calibration and Validation

Aerosol from SNPP/VIIRS
Example of VIIRS AOT product
Global high quality AOT EDR at 550 nm on May 22, 2013. True color (RGB) image is provided as background to show the absence of retrievals due to cloud, sunglint and bright surface.

The Visible Infrared Imaging Radiometer Suite (VIIRS) sensor onboard the Suomi National Polar-orbiting Partnership (SNPP) satellite provides a key set of aerosol Environmental Data Records (EDRs) based on daily global observations from space. These products are:

  • Aerosol Optical Thickness (AOT), providing a measure of the aerosol content of the atmospheric column,
  • Aerosol Particle Size Parameter (APSP), given as the Ångström Exponent (AE), a qualitative measure of particle size with larger AE corresponding to smaller particles, and vice-versa,
  • Suspended Matter (SM), indicating the presence of dust, smoke, sea salt, volcanic ash above a threshold amount.

More information on these products is available from the Products page. Detailed instructions on how to access the data from their official archive location at the NOAA Comprehensive Large Array-data Stewardship System (CLASS) are provided in the subpages of the Products page.

Reprocessed VIIRS aerosol data

The Aerosol Team generated a new version of reprocessed AOD and ADP products for Suomi NPP VIIRS using the Enterprise Processing System (EPS) algorithms. This version has the best possible calibration updates to the VIIRS Sensor Data Records (SDRs) and algorithm updates, including retrievals over bright surfaces. The reprocessed AOD data have been validated against AERONET AODs and shown to meet accuracy and precision specifications for the entire range of AOD, from 0 to 5. The reprocessed ADP data have been validated as well. The reprocessed AOD and ADP products can be obtained from NOAA's Joint Polar Satellite System (JPSS) archive on Amazon Web Services (AWS)this link opens in a new window.

Global gridded aerosol optical thickness

The operational VIIRS 550-nm AOT EDRs at nominal 6-km resolution, and collected during a 24-h period, are gridded at STAR on a regular 0.25 x 0.25-degree equal angle (~28x28 km at the equator) grid.

Maps of the daily gridded AOTs can be displayed from the Gridded Data page. The gridded data can also be downloaded from the same page.

AOT movie

Animation of weekly AOT field for the first 45 weeks of 2015 is shown below. (Courtesy of the NOAA Environmental Visualization Laboratory.)

Software

Software products and tools developed by VIIRS Aerosol Cal/Val team personnel are available from the Software page.