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Full catalog/OMOCLO
OMOCLO·v004·dataset

Chlorine dioxide gas in the air (OMI/Aura)

OMI/Aura Chlorine Dioxide (OClO) Total Column 1-orbit L2 Swath 13x24 km V004 (OMOCLO) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Measures the amount of chlorine dioxide gas in the air along the satellite's path, reported as a slant column with errors and quality flags. This gas is linked to ozone-destroying chemistry.

How it's made. Retrieved from sunlight measurements by the Ozone Monitoring Instrument on NASA's Aura satellite, delivered orbit by orbit (about 14 orbits a day).

How & where you'd use it. Supports atmospheric chemistry research, especially studies of the reactions that deplete the ozone layer.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › HALOCARBONS AND HALOGENS › CHLORINE DIOXIDE

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 Aura Ozone Monitoring Instrument (OMI) collection 4 Chlorine Dioxide Product OMOCLO is now available from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for public access. The algorithm leads for this product are the US OMI scientists Dr. Kelly Chance and Dr. Gonzalo Gonzalez-Abad from the Harvard-Smithsonian Center, Cambridge, MA. The OMOCLO product contains slant column OClO, standard errors (rms and sigma), quality flags, geolocation and other ancillary information. The OMOCLO files are stored in the version 4 netCDF 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 OMOCLO data product is about 7.5 MB.

Get the data

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

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