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Full catalog/OMNO2
OMNO2·v004·dataset

Nitrogen dioxide air pollution, per orbit (Aura OMI)

OMI/Aura Nitrogen Dioxide (NO2) Total and Tropospheric Column 1-orbit L2 Swath 13x24 km V004 (OMNO2) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. How much nitrogen dioxide (a pollutant gas linked to traffic, power plants, and burning) is in the air, reported both for the full column overhead and just the lower atmosphere, measured one orbit at a time.

How it's made. Derived from the Aura OMI instrument's measurements, using updated calibration, model-based information, and corrections for instrument artifacts.

How & where you'd use it. Widely used to track air pollution and emission sources, monitor changes over cities and regions, and study atmospheric chemistry.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › NITROGEN COMPOUNDS › NITROGEN DIOXIDE › TOTAL AND TROPOSPHERIC NITROGEN DIOXIDE (NO2)

Coverage & cadence

  • Time span2004-10-01 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • 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 Collection 4, Version 5.0, Aura Ozone Monitoring Instrument (OMI) Nitrogen Dioxide (NO2) Standard Product (OMNO2) is now available from the NASA Goddard Earth Sciences Data and Information Services Center. The major V5.0 updates include the use of: (1) improved Collection 4 Level-1B radiance and irradiance data in the retrieval of NO2 and O2-O2 slant columns; (2) a-priori NO2 profiles and other model-derived information from a high-resolution (~25 km) Global Modeling Initiative (GMI) simulation; (3) a new algorithm for improved de-striping and data flagging to correct for cross-track artifacts and row-anomaly; (4) updated geometry dependent surface Lambertian Equivalent Reflectivity (GLER) and consistently-retrieved O2-O2 cloud products; and (5) improved snow/ice database and treatment in the GLER, cloud, and NO2 algorithms. The details can be found in the updated OMNO2 readme document (see Documentation). The OMNO2 product contains NO2 slant column density (SCD), total NO2 vertical column density (VCD), the stratospheric and tropospheric VCDs, air mass factors (AMFs), scattering weights for AMF calculation, and other ancillary data used in the OMNO2 algorithm. The OMI NO2 files are stored in version 5 EOS Hierarchical Data Format (HDF-EOS5). The short name for the Level-2 swath type column NO2 products is OMNO2. Each Level-2 file contains data from the day lit portion of an orbit (~53 minutes). There are approximately 14 orbits per day. The maximum file size for the OMNO2 is ~21 MB. Other OMNO2-associated NO2 products include the Level-2 gridded column product, OMNO2G, and the Level-3 gridded column product, OMNO2d.

Get the data

omno2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMNO2",
    version="004",
    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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.