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Full catalog/ML2SO2_NRT
ML2SO2_NRT·v005·dataset

Sulfur dioxide high in the atmosphere, near real-time (MLS, Aura)

MLS/Aura Near-Real-Time L2 Sulfur Dioxide (SO2) Mixing Ratio V005 (ML2SO2_NRT) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Near real-time vertical profiles of sulfur dioxide gas high in the atmosphere, showing how much of this gas is present at different altitudes.

How it's made. Derived quickly from microwave energy measured by the Microwave Limb Sounder on NASA's Aura satellite, using a fast simplified method so data arrive within a few hours.

How & where you'd use it. Helps track sulfur dioxide from major volcanic eruptions soon after they happen. Because it is the quick version, it is less accurate than the standard product and best for time-sensitive monitoring.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › SULFUR COMPOUNDS › SULFUR DIOXIDE

Coverage & cadence

  • Time span2021-09-21 → ongoing
  • Measured byAura (MLS)
  • Processing levelLevel 2
  • Spatial extent-180, -82, 180, 82
  • 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

ML2SO2_NRT is the EOS Aura Microwave Limb Sounder (MLS) Near-Real-Time (NRT) product for sulfur dioxide (SO2). This product contains SO2 profiles derived from the 190 and 240 GHz regions. The NRT data are typically available within 3 hours of observation and are broken into files containing about 15 minutes of data. The most recent 7 days of data are available online. Spatial coverage is near-global (-82 degrees to +82 degrees latitude), with each profile spaced 1.5 degrees or ~165 km along the orbit track (roughly 15 orbits per day). The vertical coverage is from 215 to 10 hPa. The MLS NRT algorithm uses a simplified fast forward model to meet Near Real Time data latency requirements and are therefore not as accurate as the retrievals that constitute the standard MLS products. Nevertheless the results are scientifically useful in selected regions of the Earth's atmosphere provided that the data are screened according to the recommendations in the MLS NRT User Guide and the MLS L2 Data Quality Document for Standard Products.

Get the data

ml2so2_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="ML2SO2_NRT",
    version="005",
    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.