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Full catalog/OMCLDO2Z
OMCLDO2Z·v003·dataset

Cloud height and cloud cover, zoomed-in (OMI, Aura)

OMI/Aura Cloud Pressure and Fraction (O2-O2 Absorption) Zoomed 1-Orbit L2 Swath 13x12km V003 (OMCLDO2Z) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. Cloud information at fine detail: how high the clouds sit (their pressure) and how much of each pixel they cover, along with viewing angles and quality flags.

How it's made. Retrieved from the OMI instrument on the Aura satellite by analyzing how oxygen molecules absorb light near 477 nanometers, delivered as a high-resolution 'zoomed' view that's collected only once a month.

How & where you'd use it. Helps scientists account for clouds when measuring air pollution and ozone, since cloud height and cover affect those readings; it's mostly a supporting input for atmospheric studies.

What's measured

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

Coverage & cadence

  • Time span2004-10-06 → 2019-11-12
  • Measured byAura (OMI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • StatusCOMPLETE

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) Level-2 zoomed cloud data product OMCLDO2Z at 13x12 km resolution is now available from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for the public access. It is the second release of Version 003 and was reprocessed late 2011. OMI provides two cloud products based on two different algorithms, the Rotational Raman Scattering method and O2-O2 absorption method using the DOAS technique. This level-2 zoomed cloud product at the pixel resolution (13x12 km2 at nadir) is based on the spectral fitting of O2-O2 absorption band at 477 nm using DOAS technique. This product contains effective cloud pressure, effective cloud fraction, slant column O2-O2; uncertainties in derived, parameters, terrain and geolocation information, solar and satellite viewing angles, and quality flags. The shortname for this Level-2 OMI Zoomed cloud product is OMCLDO2Z. The lead scientist for this product is Dr. Pepijn Veefkind. The OMCLDO2Z files are stored in the version 5 Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (~53 minutes) and is roughly 20 MB in size. OMCLDO2Z data files are based on Zoomed Level 1B radiance observations which are made once a month. Thus there is one zoomed cloud product per month.

Get the data

omcldo2z_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMCLDO2Z",
    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.