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Full catalog/OML1BRUG
OML1BRUG·v003·dataset

Raw ultraviolet light reflected off Earth (Aura)

OMI/Aura Level 1B UV Global Geolocated Earthshine Radiances 1-orbit L2 Swath 13x24 km V003 (OML1BRUG) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. Raw readings of how much ultraviolet light Earth reflected back to space, broken out wavelength by wavelength, before any pollution or ozone amounts have been calculated.

How it's made. Recorded by the OMI instrument on the Aura satellite as it scans across its track, capturing the daylit side of each orbit; this is the lowest-level, geolocated measurement stage.

How & where you'd use it. A raw building-block input that scientists feed into higher-level products for ozone and air quality, rather than something most people would open directly.

What's measured

SPECTRAL/ENGINEERING › ULTRAVIOLET WAVELENGTHS › ULTRAVIOLET RADIANCE

Coverage & cadence

  • Time span2004-10-01 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The Aura Ozone Monitoring Instrument (OMI) Level-1B (L1B) Geo-located Earth View UV Radiance, Global-Mode (OML1BRUG) Version-3 product contains geo-located Earth view spectral radiances from the UV detectors in the wavelength range of 264 to 383 nm conducted in the global measurement mode. In the standard global measurement mode, OMI observes 60 ground pixels (13 km x 24 km at nadir) across the swath for each of the 557 channels of UV2 (307-383 nm) and 30 ground pixels (13 km x 48 km at nadir) for the 159 channels of UV1 (264-311 nm). Each file contains data from the day lit portion of an orbit (~53 minutes) and is roughly 180 MB in size. There are approximately 14 orbits per day. Once a month, in one orbit, OMI performs dark measurements, it does not perform radiance measurements. In addition, OMI performs spatial zoom measurements one day per month. For that day, this product also contains UV2 measurements that are rebinned from the spatial zoom-in measurements. In original spatial zoom mode the nadir ground pixel size is 13 x 12 km and measurements are available only for the UV2 and VIS wavelengths (306 to 432 nm). The shortname for this OMI Level-1B Product is OML1BRUG. The lead algorithm scientist for this product is Dr. Marcel Dobber from the Royal Netherlands Meteorological Institude (KNMI). The OML1BRUG files are stored in the HDF4 based EOS Hierarchical Data Format (HDF-EOS). The radiances for the earth measurements (also referred as signal) and its precision are stored as a 16 bit mantissa and an 8-bit exponent. The signal can be computed using the equation: signal = mantissa x 10^exponent. For the precision, the same exponent is used as for the signal.

Get the data

oml1brug_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OML1BRUG",
    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.