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Full catalog/OMNO2G
OMNO2G·v003·dataset

Nitrogen dioxide air pollution (Aura, daily grid)

OMI/Aura NO2 Total and Tropospheric Column Daily L2 Global Gridded 0.25 degree x 0.25 degree V3 (OMNO2G) at GES DISC
atmosphere NASA GES_DISC Level 2G active
In plain English

What it measures. This measures nitrogen dioxide, a gas linked to combustion and poor air quality, in the air column over each spot on Earth, both in the troposphere near the ground and overall. It is provided as a daily global grid.

How it's made. It comes from the OMI instrument on NASA's Aura satellite; individual measurements are sorted into quarter-degree grid cells without averaging, preserving the raw pixel values.

How & where you'd use it. Useful for tracking air pollution from traffic, industry, and power plants, and for studying ozone chemistry in the atmosphere.

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 2G
  • 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

This Level-2G daily global gridded product OMNO2G is based on the pixel level OMI Level-2 NO2 product OMNO2. OMNO2G data product is a special Level-2 Gridded Product where pixel level data are binned into 0.25x0.25 degree global grids. It contains the data for all L2 scenes that have observation time between UTC times of 00:00:00 and 23:59:59.9999. All data pixels that fall in a rid box are saved Without Averaging. Nitrogen dioxide is an important chemical species in both the stratosphere, where it plays a key role in ozone chemistry, and in the troposphere, where it is a precursor to ozone production. In the troposphere, it is produced in various combustion processes and in lightning and is an indicator of poor air quality. The OMNO2G data product contains almost all parameters that are contained in OMNO2 product. The OMNO2G data are stored in version 5 EOS Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of the orbit (~14 orbits). The average file size for the OMNO2G data product is about 115 Mbytes.

Get the data

omno2g_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMNO2G",
    version="003",
    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.