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Full catalog/OMPS_N20_NMSO2_PCA_L2_Step1
OMPS_N20_NMSO2_PCA_L2_Step1·v1·dataset

Sulfur dioxide pollution in the air (NOAA-20)

OMPS-N20 NM PCA SO2 Step 1 Total Column 1-Orbit L2 Swath 17x13km
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. The total amount of sulfur dioxide in a column of air, a gas released by volcanoes and industrial pollution. It estimates amounts assuming the gas sits at several possible heights, from near the ground up into the stratosphere.

How it's made. Retrieved from the OMPS instrument on the NOAA-20 satellite using a spectral-fitting method developed at NASA Goddard, delivered one orbit at a time.

How & where you'd use it. Tracks volcanic plumes and pollution sources, helping with air-quality monitoring and aviation safety when eruptions inject sulfur dioxide into the air.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › SULFUR COMPOUNDS › SULFUR DIOXIDE

Coverage & cadence

  • Time span2018-01-16 → ongoing
  • Measured byNOAA-20 (OMPS)
  • Processing levelLevel 2
  • 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 OMPS-N20 NM PCA SO2 Step1 Total Column 1-Orbit L2 Swath 17x13km collection 1 product contains the retrieved sulfur dioxide (SO2) measured by the Ozone Mapping and Profiling Suite (OMPS) Nadir-Mapper (NM) sensor on the NOAA-20 (JPSS-1) satellite. The product is based on the NASA Goddard Space Flight Center principal component analysis (PCA) spectral fitting algorithm (Li et al., 2013, 2017) used to retrieve the SO2 total column amounts assuming different SO2 plume heights, including the boundary layer (lowest 1 km of the atmosphere), the lower (centered at 3 km), middle (centered at 8 km) and upper (centered at 13 km) troposphere, as well as the lower stratosphere (centered at 18 km). Each granule contains data from the daylight portion for a single orbit or about 50 minutes. Spatial coverage is global (-90 to 90 degrees latitude), and there are about 14 orbits per day each with a swath width of 2600 km. There are 104 pixels in the cross-track direction before February 13, 2019 with a pixel resolution of about 17 km x 17 km at nadir. Since then, the pixel resolution has been enhanced to 17 km x 13 km at nadir, with 140 pixels in the cross-track direction. The files are written using netCDF version 4.

Get the data

omps_n20_nmso2_pca_l2_step1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMPS_N20_NMSO2_PCA_L2_Step1",
    version="1",
    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.