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Full catalog/XAERDT_L2_VIIRS_NOAA20
XAERDT_L2_VIIRS_NOAA20·v1·dataset

Haze, dust and smoke over dark land (NOAA-20, 6 km)

VIIRS/NOAA20 Dark Target Aerosol L2 6-Min Swath 6 km
atmosphere NASA LAADS Level 2 netCDF-4
In plain English

What it measures. Maps of how much haze, dust, and smoke is in the air over darker land surfaces, plus related aerosol details, at about 6 kilometers per pixel.

How it's made. Produced from the VIIRS sensor on the NOAA-20 satellite using a version of the MODIS 'Dark Target' algorithm, part of a project that harmonizes aerosol products across many satellites.

How & where you'd use it. Useful for air-quality monitoring and tracking pollution, dust, and smoke, and designed to give consistent results that can be compared across different satellites.

What's measured

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

Coverage & cadence

  • Time span2019-01-01 → 2023-01-01
  • 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 L2 Dark Target Aerosol 6-Min L2 Swath 6 km product, short-name XAERDT_L2_VIIRS_NOAA20 is provided at 6-km spatial resolution (at-nadir) and a 6-minute cadence that typically yields about 130 granules over the daylit hours of a 24-hour period. The NOAA20/VIIRS L2 collection record spans from January 2019 through December 2022. The XAERDT_L2_VIIRS_NOAA20 product is a part of the Geostationary Earth Orbit (GEO)–Low-Earth Orbit (LEO) Dark Target Aerosol project under NASA’s Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, led by Robert Levy, uses a special version of the MODIS Dark Target (DT) aerosol retrieval algorithm to produce Aerosol Optical Depth (AOD) and other aerosol parameters derived independently from seven sensor/platform combinations, where 3 are in GEO and 4 are in LEO. The 3 GEO sensors include Advanced Baseline Imagers (ABI) on both GOES-16 (GOES-East) and GOES-17 (GOES-West), and Advanced Himawari Imager (AHI) on Himawari-8. The 4 LEO sensors include MODIS on both Terra and Aqua, and VIIRS on both Suomi-NPP and NOAA-20. Adding the LEO sensors reinforces a major goal of this project, which is to render a consistent science maturity level across DT aerosol products derived from both types and sources of orbital satellites. The XAERDT_L2_VIIRS_NOAA20 product, in netCDF4 format, contains 45 Science Data Set (SDS) layers that include 8 geolocation and 37 geophysical SDSs. For more information consult LAADS [product description page](https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/XAERDT_L2_VIIRS_NOAA20) or [Dark Target aerosol team page](https://darktarget.gsfc.nasa.gov/)

Get the data

xaerdt_l2_viirs_noaa20_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="XAERDT_L2_VIIRS_NOAA20",
    version="1",
    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.