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Full catalog/OMDOAO3
OMDOAO3·v004·dataset

Total ozone overhead (OMI)

OMI/Aura DOAS Total Column Ozone 1-Orbit L2 Swath 13x24 km V004 (OMDOAO3) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. The total amount of ozone in a column of air from the ground all the way up, measured spot by spot along the satellite's track at roughly 13-by-24-km resolution, along with many supporting parameters.

How it's made. Produced by the Ozone Monitoring Instrument on NASA's Aura satellite using a light-absorption fitting technique on ultraviolet wavelengths, in this case the reprocessed version 4 release.

How & where you'd use it. Used to monitor Earth's protective ozone layer and how it changes, which matters for understanding ultraviolet exposure at the surface.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONE › TOTAL COLUMN OZONE (O3)

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 Level-2 Aura Ozone Monitoring Instrument (OMI) Ozone (O3) DOAS Total Column Product (OMDOAO3) version 4 is now available from NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for public access. The shortname for this Level-2 Ozone Product is OMDOAO3_V004. The data was re-processed in December 2022 using collection 4 Level 1b data and the OMDOAO3 processor version 4.1.0. Since then, this version of the product is also being produced in the forward stream. This version of the product was publicly released in March 2026. OMI provides two total column ozone products based on two different algorithms. This level-2 global total column ozone product at the pixel resolution (13x24 km at nadir), is based on the Differential Absorption Spectroscopy (DOAS) fitting technique that essentially uses the OMI UV radiance values between 331.1 and 336.1 nm. In addition to the total ozone column this product also contains auxiliary , derived and ancillary input parameters e.g. ozone slant column density, ozone ghost column density, air mass factor, scene reflectivity, radiance over the DOAS fit window, root mean square of DAOS fit, cloud fraction, cloud radiance, cloud pressure, terrain height, geolocation, viewing angles and quality flags. The lead scientist for this product is Dr. J. Pepijn Veefkind. The OMDOAO3 files are stored in NetCDF 4 format. Each 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 OMDOAO3 data product is about 10 Mbytes.

Get the data

omdoao3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMDOAO3",
    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.