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Full catalog/AERDB_L2_VIIRS_NOAA20_NRT
AERDB_L2_VIIRS_NOAA20_NRT·v2·dataset

Haze, dust and smoke in the air, near-real-time (NOAA-20)

VIIRS/NOAA-20 Deep Blue Aerosol L2 6-Min Swath 6 km (v2.0)
atmosphere NASA ASIPS Level 2 active NetCDF-4
In plain English

What it measures. How much haze, dust, and smoke is in the air (aerosol optical thickness) over both land and ocean, along with related properties, delivered quickly after observation.

How it's made. Retrieved from the VIIRS instrument on the NOAA-20 satellite using the Deep Blue method over land and an ocean-specific method over water, produced as 6-kilometer swath data every 6 minutes.

How & where you'd use it. Used for near-real-time air-quality monitoring and for tracking dust storms, wildfire smoke, and pollution as they move.

What's measured

ATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESS › ANGSTROM EXPONENTATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESSATMOSPHERE › ATMOSPHERIC RADIATION › OPTICAL DEPTH/THICKNESS

Coverage & cadence

  • Time span2023-06-01 → 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 NOAA-20 Visible Infrared Imaging Radiometer Suite (VIIRS) NASA standard Level-2 (L2) deep blue aerosol product provides satellite-derived measurements of Aerosol Optical Thickness (AOT) and their properties over land and ocean, every 6 minutes, globally. The Deep Blue algorithm draws its heritage from previous applications to retrieve AOT from Sea‐viewing Wide Field‐of‐view Sensor (SeaWiFS) and Moderate Resolution Imaging Spectroradiometer (MODIS) measurements over land. 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 nanometers 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.

Get the data

aerdb_l2_viirs_noaa20_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AERDB_L2_VIIRS_NOAA20_NRT",
    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 ASIPS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.