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Full catalog/AERDB_L2_VIIRS_NOAA20
AERDB_L2_VIIRS_NOAA20·v2·dataset

Haze, dust and smoke in the air (VIIRS, NOAA-20)

VIIRS/NOAA20 Deep Blue Aerosol L2 6-Min Swath 6 km
atmosphere NASA LAADS Level 2 active NetCDF-4
In plain English

What it measures. This estimates how much haze, dust and smoke is in the air on clear, daytime, snow-free scenes, reported as how strongly airborne particles dim sunlight at a standard color, over both land and ocean.

How it's made. Derived from the VIIRS sensor on the NOAA-20 satellite using the 'Deep Blue' method over land and a companion ocean method, delivered as strips along the orbit; the record begins in early 2018.

How & where you'd use it. Used for monitoring air quality, dust storms and wildfire smoke, and for studying how airborne particles affect visibility, health and climate.

What's measured

ATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESSATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESS › ANGSTROM EXPONENT

Coverage & cadence

  • Time span2018-02-17 → ongoing
  • Measured byNOAA-20 (VIIRS)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsNetCDF-4
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

The VIIRS/NOAA20 Deep Blue Aerosol L2 6-Min Swath 6 km product from the Visible Infrared Imaging Radiometer Suite (VIIRS) determines atmospheric aerosol loading for daytime cloud-free snow-free scenes. This orbit-level product (Short-name: AERDB_L2_VIIRS_ NOAA20) has an at-nadir resolution of 6 km x 6 km, and progressively increases away from nadir given the sensor’s scanning geometry and Earth’s curvature. Viewed differently, this product’s resolution accommodates 8 x 8 native VIIRS moderate-resolution (M-band) pixels that nominally have ~750 m horizontal pixel size. The L2 Deep Blue AOT data products, at 550 nm reference wavelengths, are derived from particular VIIRS bands using two primary AOT retrieval algorithms: Deep Blue algorithm over land, and the Satellite Ocean Aerosol Retrieval (SOAR) algorithm over ocean. Although this product is called Deep Blue based on retrievals for the land algorithm, the data includes over-water retrievals as well. The Deep Blue algorithm draws its heritage from previous applications to retrieve AOT from Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) over both land and ocean and Moderate Resolution Imaging Spectroradiometer (MODIS) measurements over land. This L2 description pertains to the VIIRS Deep Blue Aerosol Version 2.0 (V2.0) product, whose record starts from February 17, 2018. The L2 netCDF product, acquired every 6 minutes, contains 55 Science Data Set (SDS) layers. The V2.0 VIIRS deep blue aerosol products are available from both NOAA20 and SNPP platforms. Significant changes have been made to the V2.0 Deep Blue/SOAR algorithms to further improve the data quality. A number of other improvements and changes have been added that can be found from Product page at: https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/AERDB_L2_VIIRS_NOAA20 Consult the VIIR Deep Blue product user guide for additional information regarding the global attributes, data field attributes, quality flags, software to handle and use these data products, etc., at: https://ladsweb.modaps.eosdis.nasa.gov/api/v2/content/archives/Document%20Archive/Science%20Data%20Product%20Documentation/VIIRS_Deep_Blue_Aerosol_User_Guide_v2.pdf

Get the data

aerdb_l2_viirs_noaa20_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AERDB_L2_VIIRS_NOAA20",
    version="2",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.