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Full catalog/OMSO2e
OMSO2e·v004·dataset

Sulfur dioxide air pollution, daily best-pixel map (OMI/Aura, 0.25 deg)

OMI/Aura Sulfur Dioxide (SO2) Total Column Daily L3 1 day Best Pixel in 0.25 degree x 0.25 degree V4 (OMSO2e) at GES DISC
atmosphere NASA GES_DISC Level 3 active
In plain English

What it measures. A daily worldwide map of sulfur dioxide pollution, showing how much of this gas is stacked up in a column of air, with one carefully chosen best observation per grid cell plus supporting details like cloud cover.

How it's made. Produced from the OMI instrument on NASA's Aura satellite, using an improved analysis method and selecting the single best-quality pixel in each grid cell to build a clean daily map.

How & where you'd use it. Tracking volcanic eruptions and industrial sulfur dioxide emissions day to day, supporting air-quality and hazard monitoring with a ready-to-use gridded map.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › SULFUR COMPOUNDS › SULFUR DIOXIDE

Coverage & cadence

  • Time span2004-10-01 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 3
  • 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 OMI science team produces this Level-3 Aura/OMI Global OMSO2e Data Products (0.25 degree Latitude/Longitude grids). In this Level-3 daily global SO2 data product, each grid contains only one observation of Total Column Density of SO2 from the GEOS-5 profile, based on an improved Principal Component Analysis (PCA) Algorithm. This single observation is the "best pixel", selected from all "good" L2 pixels of OMSO2 that overlap this grid and have UTC time between UTC times of 00:00:00 and 23:59:59.999. In addition to the SO2 Vertical column value some ancillary parameters, e.g., cloud fraction, terrain height, scene number, solar and satellite viewing angles, row anomaly flags, and quality flags have been also made available corresponding to the best selected SO2 data pixel in each grid. The OMSO2e files are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5) using the grid model.

Get the data

omso2e_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMSO2e",
    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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.