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Full catalog/ML3DZH2O
ML3DZH2O·v005·dataset

Water vapor levels by latitude, daily (Aura)

MLS/Aura Level 3 Daily Binned Water Vapor (H2O) Mixing Ratio on Zonal and Similar Grids V005 (ML3DZH2O) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. Daily measurements of how much water vapor sits at different heights in the upper atmosphere, organized in bands by latitude from near pole to near pole.

How it's made. Derived from radio-wave signals (radiances) picked up mostly by the 190 GHz instrument on NASA's Aura satellite, then averaged into daily latitude-and-altitude grids.

How & where you'd use it. Used by atmospheric scientists to track moisture high in the atmosphere and to study processes like the polar vortex and stratospheric chemistry.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROFILES › WATER VAPOR MIXING RATIO PROFILES

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

ML3DZH2O is the EOS Aura Microwave Limb Sounder (MLS) daily binned on zonal and assorted vertical grids product for water vapor (H2O) derived from radiances measured primarily by the 190 GHz radiometer. The data version is 5.1. Spatial coverage is near-global (-82 to +82 degrees latitude) at 4 degree latitude zonal increments. The recommended useful vertical range is between 316 and 0.00215 hPa, and the vertical resolution is about 1.5 km at 316 hPa increasing to 3.5 km to 4.64 hPa, and degrades to 15 km above 0.1 hPa. Users of the ML3DZH2O data product should read chapter 4 and section 3.9 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

ml3dzh2o_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML3DZH2O",
    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.