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Full catalog/AERDT_L2_VIIRS_SNPP
AERDT_L2_VIIRS_SNPP·v2·dataset

Haze, dust and smoke over dark areas (VIIRS, Suomi-NPP)

VIIRS/SNPP Dark Target Aerosol L2 6-Min Swath 6 km V2
atmosphere NASA LAADS Level 2 active netCDF-4
In plain English

What it measures. This measures how much haze, dust and smoke is in the air, focusing on retrievals over darker land and ocean surfaces, and reports the thickness of that airborne particle layer and clues about particle size over the ocean.

How it's made. Derived from the VIIRS sensor on Suomi-NPP using the long-established 'Dark Target' method (the same one used on the older MODIS instruments), delivered as 6-minute strips along the orbit.

How & where you'd use it. Used to track air quality, smoke and dust, and to study how airborne particles influence climate, weather and human health.

What's measured

ATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESSATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESS › ANGSTROM EXPONENTATMOSPHERE › AEROSOLSATMOSPHERE › AEROSOLS › AEROSOL PARTICLE PROPERTIES

Coverage & cadence

  • Time span2012-03-01 → ongoing
  • Measured bySuomi-NPP (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/SNPP Dark Target Aerosol L2 6-Min Swath 6 km product provides satellite-derived measurements of Aerosol Optical Thickness (AOT) and their properties over land and ocean, and spectral AOT and their size parameters over oceans every 6 minutes, globally. The Suomi National Polar-orbiting Partnership (SNPP) Visible Infrared Imaging Radiometer Suite (VIIRS) incarnation of the dark target (DT) aerosol product is based on the same DT algorithm that was developed and used to derive products from the Terra and Aqua mission’s MODIS instruments. Two separate and distinct DT algorithms exist. One helps retrieve aerosol information over ocean (dark in visible and longer wavelengths), while the second aids retrievals over vegetated/dark-soiled land (dark in the visible). This orbit-level product (Short-name: AERDT_L2_VIIRS_SNPP) 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. Hence, the Level-2 Dark Target Aerosol Optical Thickness data product incorporates 64 (750 m) pixels over a 6-minute acquisition. Version 2.0 constitutes the latest collection of the L2 Dark Target Aerosol product and contains improvements over its previous collection (v1.1). For more information consult LAADS [product description page](https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/AERDT_L2_VIIRS_SNPP) or [Dark Target aerosol team page](https://darktarget.gsfc.nasa.gov/).

Get the data

aerdt_l2_viirs_snpp_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AERDT_L2_VIIRS_SNPP",
    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.