The near real-time (NRT) multi-sensor blended aerosol product is generated by NASA’s Atmosphere Science Investigator-led Processing System (Atmosphere SIPS) located at the Space Science and Engineering Center (SSEC) at the University of Wisconsin-Madison.
This Level 3 product is generated by aggregating multiple aerosol products, using a consistent aggregation methodology, into one fixed grid product that includes all product variables per cell. For each product, different levels of quality controls (QA), designed for data assimilation (DA) applications, are applied. To facilitate NRT applications, the L3 product is processed in 3-hour time intervals, with the current file continuously updated until the 3 hours of observations are available. At the end of each day, a 24-hour aggregated L3 product is processed providing a daily product with global coverage.
The aerosol products that are aggregated include: the Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS)-derived NASA deep blue and dark target products, including the dark target and deep blue QA from the National Research Laboratory (NRL); and the Suomi NPP and NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS)-derived deep blue and dark target including NRL QA filtering. Each cell in the fixed grid contains the following variables from each instrument: standard deviation (std dev); aerosol optical depth (AOD) and Fine Mode Fraction; mean dark target and std dev; mean deep blue and std dev. The QA and cloud filtered dark target reflectance measurements are also included in the L3 aggregation. Each cell also contains the land ocean/mask and Normalized Difference Vegetation Index (NDVI) retrievals. Coincident Aeronet ground station data for verification will be added in future versions of the product enabling users to perform product verification and impacts of the different QA filters.
The product has a spatial resolution of 1 degree and is made available in NetCDF format. The product is updated every 5 minutes until the full 3-hour data interval is available, with each 3-hour processed Level 3 chunk made available through NASA’s Land, Atmosphere Near real-time Capability for Earth observation (LANCE). The daily product is also available once all Level 3 chunks for the day are assembled.
This blended L3 aerosol product supports both the aerosol and data assimilation communities as it provides a range of aerosol products, consistently aggregated, in one L3 file. The additional QA filtering on the aerosol products (both AOD and cloud filtered reflectance) provides a unique dataset for data assimilation applications.
To download the blended aerosol product, register for an Earthdata Login. Use the table below to access the product.