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Full catalog/ML2CH3CN
ML2CH3CN·v005·dataset

Methyl cyanide gas in the upper atmosphere

MLS/Aura Level 2 Methyl Cyanide (CH3CN) Mixing Ratio V005 (ML2CH3CN) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Amounts of methyl cyanide (CH3CN), a trace gas, high up in the atmosphere, given as vertical profiles from the lower to upper stratosphere across most of the globe.

How it's made. Derived from the natural microwave signals the gas gives off, measured by the Microwave Limb Sounder on NASA's Aura satellite as it looks sideways through the atmosphere's edge.

How & where you'd use it. A specialized product for atmospheric chemistry research; users should consult the quality documentation before relying on it.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › CARBON AND HYDROCARBON COMPOUNDS › METHYL CYANIDE

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

ML2CH3CN is the EOS Aura Microwave Limb Sounder (MLS) standard product for methyl cyanide 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 46.4 and 1.0 hPa, and the vertical resolution ranges between ~5 km in the lower stratosphere and ~10 km in the upper stratosphere. Users of the ML2CH3CN data product should read section 3.4 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

ml2ch3cn_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML2CH3CN",
    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.