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Full catalog/OMTO3
OMTO3·v004·dataset

Total ozone overhead, fast delivery (Aura, near real-time)

OMI/Aura Ozone (O3) Total Column 1-Orbit L2 Swath 13x24 km V004 NRT
atmosphere NASA OMINRT Level 2
In plain English

What it measures. The total amount of ozone overhead in each column of air, at about 13x24 km resolution along each orbit, plus extras like cloud cover and surface reflectivity. This is the fast-delivery version of the standard ozone product.

How it's made. Comes from ultraviolet readings by the Ozone Monitoring Instrument on the Aura satellite, run through the TOMS version-8 algorithm and pushed out quickly after the satellite passes.

How & where you'd use it. Used when speed matters, such as feeding daily ozone monitoring and air-quality services that need data soon after it is collected rather than waiting for the fully reprocessed version.

What's measured

ATMOSPHERE › AIR QUALITY › TROPOSPHERIC OZONEATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONE › TOTAL OZONEATMOSPHERE › ATMOSPHERIC RADIATION › REFLECTANCE

Coverage & cadence

  • Time span2004-07-15 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • StatusNOT PROVIDED

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 Aura Ozone Monitoring Instrument (OMI) Level-2 Total Column Ozone Data Product OMTO3 (Collection Version 004) Near Real Time (NRT) is available from the NASA OMINRT for the public access. This level-2 global total column ozone product (OMTO3) is based on the enhanced TOMS version-8 algorithm that essentially uses the ultraviolet radiance data at 317.5 and 331.2 nm at a pixel resolution of 13 x 24 km at nadir. OMI hyper-spectral measurements help in the corrections for the factors that induce uncertainty in ozone retrievals (e.g., cloud and aerosol, sea-glint effects, profile shape sensitivity, SO2 and other trace gas contamination). In addition to the total ozone values this product also contains some auxiliary derived and ancillary input parameters including N-values, effective Lambertian scene-reflectivity, cloud fraction, cloud pressure, ozone below clouds, terrain height, geolocation, solar and satellite viewing angles, and quality flags. The shortname for this Level-2 OMI total column ozone product is OMTO3. The algorithm for this product was originally developed by a team led by Dr. Pawan K. Bhartia at NASA Goddard Space Flight Center. The current product lead is Dr. Can Li. The OMTO3 files are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5). 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 OMTO3 data product is approximately 35 MB.

Get the data

omto3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMTO3",
    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 OMINRT
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.