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Full catalog/ML3DBCH3CL
ML3DBCH3CL·v005·dataset

Methyl chloride high in the atmosphere, daily (Aura)

MLS/Aura Level 3 Daily Binned Methyl Chloride (CH3Cl) Mixing Ratio on Assorted Grids V005 (ML3DBCH3CL) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. Daily amounts of methyl chloride (a chlorine-carrying gas) high up in the atmosphere, reported across different altitudes and as near-global maps and averages.

How it's made. Derived from the Microwave Limb Sounder on NASA's Aura satellite, which senses the gas's signature in microwave energy, then binned onto various vertical grids as a Level-3 product.

How & where you'd use it. Supports studies of atmospheric chemistry, especially chlorine-bearing gases relevant to the ozone layer, with coverage from 2005 onward.

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

ML3DBCH3CL is the EOS Aura Microwave Limb Sounder (MLS) daily binned on various 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 a spatial resolution of 4 degrees latitude by 5 degrees longitude. 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 ML3DBCH3CL 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 are archived in the netCDF4 format, which is also compatible with HDF5 readers and tools. Each file contains six group objects: lat-lon map vs pressure, lat vs pressure zonal mean, lat-lon map vs "potential temperature", 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

ml3dbch3cl_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML3DBCH3CL",
    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.