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Full catalog/ML2O3
ML2O3·v005·dataset

Ozone amounts high in the atmosphere (Aura MLS)

MLS/Aura Level 2 Ozone (O3) Mixing Ratio V005 (ML2O3) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. How much ozone is present high up in the atmosphere, given as vertical profiles that show the amount at different altitudes, nearly worldwide.

How it's made. Calculated from microwave signals naturally emitted by the atmosphere and picked up by the Microwave Limb Sounder on NASA's Aura satellite, which scans the edge of the atmosphere about 15 times a day.

How & where you'd use it. Supports research on the ozone layer, atmospheric chemistry, and how the upper atmosphere changes over time.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONE

Coverage & cadence

  • Time span2004-08-02 → ongoing
  • Measured byAura (MLS)
  • Processing levelLevel 2
  • Spatial extent-180, -82, 180, 82
  • 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

ML2O3 is the EOS Aura Microwave Limb Sounder (MLS) standard product for ozone derived from radiances measured by the 240 GHz radiometer. The data version is 5.0. Spatial coverage is near-global (-82 degrees to +82 degrees latitude), with each profile spaced 1.5 degrees or ~165 km along the orbit track (roughly 15 orbits per day). The recommended useful vertical range is from 261 to 0.0215 hPa, and the vertical resolution is between 2.5 and 6 km. Users of the ML2O3 data product should read section 3.18 of the EOS MLS Level 2 Version 5 Quality Document for more information. The data are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5), which is based on the version 5 Hierarchical Data Format, or HDF-5. Each file contains two swath objects (profile and column data), each with a set of data and geolocation fields, swath attributes, and metadata.

Get the data

ml2o3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML2O3",
    version="005",
    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.