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Full catalog/ML3DBHNO3
ML3DBHNO3·v005·dataset

Nitric acid in the upper atmosphere (Aura, daily)

MLS/Aura Level 3 Daily Binned Nitric Acid (HNO3) Mixing Ratio on Assorted Grids V005 (ML3DBHNO3) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. This measures nitric acid in the upper atmosphere, reported as its concentration at various heights and summarized on daily grids. Nitric acid plays a role in stratospheric chemistry, including the processes behind the ozone layer.

How it's made. It is derived from microwave radiation measured by the Microwave Limb Sounder on NASA's Aura satellite, binned daily onto several vertical and map grids, covering data from 2005 onward.

How & where you'd use it. Helps scientists study the chemistry of the stratosphere, including ozone-related processes and polar conditions.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › NITROGEN COMPOUNDS › ATMOSPHERIC NITRIC ACID

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

ML3DBHNO3 is the EOS Aura Microwave Limb Sounder (MLS) daily binned on various vertical grids product for nitric acid (HNO3) derived from radiances measured by the 240 GHz radiometer at and below 10 hPa, and from the 190 GHz radiometer above 10 hPa. 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 from 215 to 1.47 hPa (1.0 hPa under enhanced conditions), and the vertical resolution is between about 3 and 5 km. Users of the ML3DBHNO3 data product should read chapter 4 and section 3.12 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

ml3dbhno3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML3DBHNO3",
    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.