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Full catalog/ML2CH3CL
ML2CH3CL·v005·dataset

Methyl chloride gas in the air (Aura)

MLS/Aura Level 2 Methyl Chloride (CH3CL) Mixing Ratio V005 (ML2CH3CL) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Reports how much methyl chloride gas is present at different heights in the upper atmosphere, given as a mixing ratio, in vertical profiles spaced about 165 km apart along the orbit.

How it's made. Derived from a 640 GHz radiometer on NASA's Aura satellite, which reads faint microwave signals from the gas along the edge of the atmosphere.

How & where you'd use it. Helps scientists study atmospheric chemistry, particularly chlorine compounds that play a role in the ozone layer, covering 2004 to today.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › HALOCARBONS AND HALOGENS › METHYL CHLORIDE

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

ML2CH3CL is the EOS Aura Microwave Limb Sounder (MLS) standard product for methyl chloride derived from radiances measured by the 640 GHz radiometer. The data version is 5.0. Data coverage is from August 8, 2004 to current. 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 between 147 and 4.64 hPa, and the vertical resolution ranges between 4-6 km in the lower stratosphere and 8-10 km above 14 hPa. Users of the ML2CH3CL data product should read section 3.3 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 one swath object (profile data), with a set of data and geolocation fields, swath attributes, and metadata.

Get the data

ml2ch3cl_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML2CH3CL",
    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.