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Full catalog/ML3DBRHI
ML3DBRHI·v005·dataset

How close the upper air is to making ice clouds (daily)

MLS/Aura Level 3 Daily Binned Relative Humidity With Respect To Ice (RHI) on Assorted Grids V005 (ML3DBRHI) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. How close the upper atmosphere is to the point where water vapor would freeze into ice clouds, expressed as humidity relative to ice across a range of heights, covering most of the globe.

How it's made. Derived from radiances measured by the Microwave Limb Sounder on the Aura satellite, then averaged into daily bins on several vertical and map grids.

How & where you'd use it. Helps scientists study high-altitude clouds, water vapor in the upper atmosphere, and conditions that affect climate, stored in a format ready for analysis.

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 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

ML3DBRHI is the EOS Aura Microwave Limb Sounder (MLS) daily binned on various vertical grids product for relative humidity with respect to ice (RHI) derived from radiances measured by the 118 and 190 GHz radiometers. The data version is 5.1. 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 316 to 0.0215 hPa, and the vertical resolution is between 3 and 6 km. Users of the ML3DBRHI data product should read chapter 4 and section 3.20 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 theta, lat vs theta zonal mean, equivalent lat vs theta zonal mean, and vortex average vs theta. Each group has a set of data (average, min, max, std dev, rms) and geolocation fields, grid attributes, and metadata.

Get the data

ml3dbrhi_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML3DBRHI",
    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.