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Full catalog/ML3MBHCL
ML3MBHCL·v005·dataset

Hydrogen chloride gas, monthly (Aura)

MLS/Aura Level 3 Monthly Binned Hydrogen Chloride (HCl) Mixing Ratio on Assorted Grids V005 (ML3MBHCL) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. Monthly amounts of hydrogen chloride gas in the atmosphere, organized by latitude and altitude. This gas is the main reservoir that locks away chlorine, so tracking it helps gauge the ozone layer's chemical state.

How it's made. Derived mainly from 640 GHz microwave signals recorded by the Microwave Limb Sounder on NASA's Aura satellite, then averaged into monthly bins.

How & where you'd use it. Helps researchers monitor how chlorine is stored in the stratosphere and how ozone-protection efforts are playing out over time.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › HALOCARBONS AND HALOGENS › HYDROGEN 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

ML3MBHCL is the EOS Aura Microwave Limb Sounder (MLS) monthly binned on various vertical grids product for hydrogen chloride (HCl) derived from radiances measured primarily by the 640 GHz radiometer. The data version is 5.1. Spatial coverage is near-global (-82 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 100 to 0.316 hPa, and the vertical resolution is between 3 and 6 km. Users of the ML3MBHCL data product should read chapter 4 and section 3.10 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 two grid objects (profile and column data), each with a set of data and geolocation fields, grid attributes, and metadata.

Get the data

ml3mbhcl_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML3MBHCL",
    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.