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Full catalog/ML2RHI
ML2RHI·v005·dataset

Humidity relative to ice, high in the air (MLS, Aura)

MLS/Aura Level 2 Relative Humidity With Respect To Ice V005 (ML2RHI) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. How humid the air is relative to ice high in the atmosphere, reported as profiles at different altitudes.

How it's made. Derived from microwave signals measured by the MLS instrument on NASA's Aura satellite, which scans the edge of the atmosphere.

How & where you'd use it. Helps scientists study high-altitude clouds and the moisture conditions where ice can form.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITY › RELATIVE HUMIDITY

Coverage & cadence

  • Time span2004-08-02 → ongoing
  • Measured byAura (MLS)
  • Processing levelLevel 2
  • 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

ML2RHI is the EOS Aura Microwave Limb Sounder (MLS) standard product for relative humidity with respect to ice derived from radiances measured by the 118 and 190 GHz radiometers. The data version is 5.0. Spatial coverage is near-global (-82 degrees 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 316 to 0.0215 hPa, and the vertical resolution is between 3 and 6 km. Users of the ML2RHI data product should read section 3.20 of the EOS MLS Level 2 Version 5 Quality Document for more information. The data are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5), which is based on the version 5 Hierarchical Data Format, or HDF-5. Each file contains two swath objects (profile and column data), each with a set of data and geolocation fields, swath attributes, and metadata.

Get the data

ml2rhi_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML2RHI",
    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.