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Full catalog/OMCLDRR
OMCLDRR·v003·dataset

Cloud height and cover from scattered light (Aura)

OMI/Aura Effective Cloud Pressure and Fraction (Raman Scattering) 1-Orbit L2 Swath 13x24 km V003 (OMCLDRR) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Estimates how high clouds sit and how much of each satellite view they cover, by reading a subtle fingerprint that scattered sunlight leaves in the spectrum.

How it's made. Retrieved from the OMI instrument on NASA's Aura satellite using the Rotational Raman Scattering method, delivered orbit-by-orbit as a reprocessed Level-2 product.

How & where you'd use it. Mostly a supporting input that helps correct other measurements (like ozone and pollution) for the influence of clouds, rather than something the public reads directly.

What's measured

ATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD FRACTIONATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD TOP PRESSURE

Coverage & cadence

  • Time span2004-10-01 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • 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

The reprocessed Aura Ozone Monitoring Instrument (OMI) Version 003 Level 2 Cloud Data Product OMCLDRR is available to the public from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC). Aura OMI provides two Level-2 Cloud products (OMCLDRR and OMCLDO2) at pixel resolution (13 x 24 km at nadir) that are based on two different algorithms, the Rotational Raman Scattering method and the O2-O2 absorption method. This level-2 global cloud product, OMCLDRR, provides effective cloud pressure and effective cloud fraction that is based on the least square fitting of the Ring spectrum (filling-in of Fraunhofer lines in the range 392 to 398 nm due to rotational Raman scattering). This product also contains many ancillary and derived parameters, terrain and geolocation information, solar and satellite viewing angles, and quality flags. The shortname for this Level-2 OMI Cloud Pressure and Fraction product is OMCLDRR and the algorithm lead for this product is NASA OMI scientist Dr. Joanna Joinner. The OMCLDRR files are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (53 minutes). There are approximately 14 orbits per day. The maximum file size for the OMCLDRR data product is about 9 Mbytes.

Get the data

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

results = earthaccess.search_data(
    short_name="OMCLDRR",
    version="003",
    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.