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Full catalog/OMNO2d
OMNO2d·v004·dataset

Nitrogen dioxide air pollution, mapped daily (Aura OMI)

OMI/Aura NO2 Cloud-Screened Total and Tropospheric Column L3 Global Gridded 0.25 degree x 0.25 degree V004 (OMNO2d) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. Daily worldwide maps of nitrogen dioxide, a common air pollutant, showing both the total amount in the air column and the portion in the lower atmosphere, on a fine 0.25-degree grid.

How it's made. Built from the OMI instrument on NASA's Aura satellite by taking good-quality individual measurements and averaging them into daily global grids.

How & where you'd use it. Used to monitor air quality and pollution from traffic, industry, and combustion, and to study atmospheric chemistry, since nitrogen dioxide is both an air-quality indicator and a player in ozone formation.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › NITROGEN COMPOUNDS › NITROGEN DIOXIDE

Coverage & cadence

  • Time span2004-10-01 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 3
  • 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 is Level-3 daily global gridded (0.25x0.25 degree) Nitrogen Dioxide Product (OMNO2d). OMNO2d data product is a Level-3 Gridded Product where pixel level data of good quality are binned and "averaged" into 0.25x0.25 degree global grids. This product contains Total column NO2 and Total Tropospheric Column NO2, for all atmospheric conditions, and for sky conditions where cloud fraction is less than 30 percent. 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 OMNO2d data are stored in version 5 EOS Hierarchical Data Format (HDF-EOS). Each file contains data from the day lit portion of the orbit (~14 orbits). The average file size for the OMNO2d data product is about 12 Mbytes.

Get the data

omno2d_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMNO2d",
    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.