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Full catalog/OMCLDO2G
OMCLDO2G·v003·dataset

Cloud pressure and cover, daily gridded (OMI)

OMI/Aura Cloud Pressure and Fraction (O2-O2 Absorption) Daily L2 Global Gridded 0.25 degree x 0.25 degree V3 (OMCLDO2G) at GES DISC
atmosphere NASA GES_DISC Level 2G active
In plain English

What it measures. Daily information about clouds worldwide: the air pressure at cloud level (a proxy for cloud height) and how much of each grid area is cloud-covered, plus related measurements and quality flags.

How it's made. Made by the Ozone Monitoring Instrument on NASA's Aura satellite, which detects clouds via a light-absorption feature near 477 nm, with individual measurements binned into a 0.25-degree grid without averaging.

How & where you'd use it. A building-block input that scientists filter and combine themselves; cloud information like this is essential for correcting and interpreting other satellite measurements of the atmosphere.

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 2G
  • 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

This Level-2G daily global gridded product OMCLDO2G is based on the pixel level OMI Level-2 CLDO2 product OMCLDO2. This level-2G global cloud product (OMCLDO2G) is based on the spectral fitting of O2-O2 absorption band at 477 nm using DOAS technique. This product contains cloud pressure, cloud fraction, slant column O2-O2 and Ozone, Ring coefficients, uncertainties in derived parameters, terrain and geolocation information, solar and satellite viewing angles, and quality flags. The short name for this Level-2 OMI cloud product is OMCLDO2G and the lead scientist for this product and for OMCLDO2 (the data source of OMCLDO2G) is KNMI scientist Dr. Pepijn Veefkind. OMCLDO2G data product is a special Level-2 Global Gridded Product where pixel level data (OMCLDO2) are binned into 0.25x0.25 degree global grids. It contains the OMCLDO2 data for all L2 scenes that have observation time between UTC times of 00:00:00 and 23:59:59.9999. All data pixels that fall in a grid are saved 'Without Averaging'. Scientists can apply a data filtering scheme of their choice and create new gridded products. The OMCLDO2G product files are stored in the version 5 Hierarchical Data Format (HDF-EOS5). Each daily data file contains data from the day lit portion of the orbits (~14 orbits) and is roughly 85 MB in size.

Get the data

omcldo2g_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMCLDO2G",
    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.