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Full catalog/OMCLDRR
OMCLDRR·v004·dataset

Cloud height and cloud cover, fast preview version

OMI/Aura Effective Cloud Pressure and Fraction (Raman Scattering) 1-Orbit L2 Swath 13x24 km V004 (OMCLDRR) OMINRT
atmosphere NASA OMINRT Level Not provided HDF-EOS5
In plain English

What it measures. The same cloud-height (as air pressure) and cloud-cover information as the standard product, derived from how clouds bend the color of scattered sunlight.

How it's made. Produced from the Ozone Monitoring Instrument on NASA's Aura satellite, but in a 'near real time' fast-turnaround version that trades a little polish for speed.

How & where you'd use it. Meant for time-sensitive work where having cloud information quickly matters more than waiting for the final, fully checked version; the standard product is available separately for careful research.

What's measured

ATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD FRACTION

Coverage & cadence

  • Time span2004-07-15 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel Not provided
  • Spatial extent-180, 90, 180, 90
  • FormatsHDF-EOS5
  • StatusNOT PROVIDED

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

This is the Aura Ozone Monitoring Instrument (OMI) Version 004 Near Real TIme (NRT) Level 2 Cloud Data Product OMCLDRR. 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. OMI Standard products are available at the GES DISC.

Get the data

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

results = earthaccess.search_data(
    short_name="OMCLDRR",
    version="004",
    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 OMINRT
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.