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Full catalog/ML3DZCH3CL
ML3DZCH3CL·v005·dataset

Methyl chloride gas by latitude, daily (Aura)

MLS/Aura Level 3 Daily Binned Methyl Chloride (CH3Cl) Mixing Ratio on Zonal and Similar Grids V005 (ML3DZCH3CL) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. Daily amounts of methyl chloride gas in the atmosphere, summarized by latitude band and altitude. Methyl chloride is a chlorine-carrying gas relevant to the ozone layer.

How it's made. Derived from microwave signals recorded by the Microwave Limb Sounder on NASA's Aura satellite, then averaged into latitude-and-height bins.

How & where you'd use it. Used by atmospheric scientists to study the chemistry of the stratosphere and the natural sources of chlorine that affect ozone.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › HALOCARBONS AND HALOGENS › METHYL CHLORIDE

Coverage & cadence

  • Time span2004-08-02 → ongoing
  • Measured byAura (MLS)
  • Processing levelLevel 3
  • 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

ML3DZCH3CL is the EOS Aura Microwave Limb Sounder (MLS) daily binned on zonal and assorted vertical grids product for methyl chloride (CH3Cl) derived from radiances measured by the 640 GHz radiometer. The data version is 5.1. Data coverage is from August 2, 2005 to current. Spatial coverage is near-global (-82 to +82 degrees latitude) at 4 degree latitude zonal increments. 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 ML3DZCH3CL data product should read chapter 4 and section 3.3 of the EOS MLS Level 2 Version 5 Quality Document for more information. The data files contain one year of data and are archived in the netCDF4 format, which is also compatible with HDF5 readers and tools. Each file contains four group objects: lat vs pressure zonal mean, lat vs "potential temperature" zonal mean, "equivalent latitude" vs "potential temperature" zonal mean, and vortex average vs "potential temperature". Each group has a set of data (average, min, max, std dev, rms) and geolocation fields, grid attributes, and metadata.

Get the data

ml3dzch3cl_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML3DZCH3CL",
    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.