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Full catalog/PACE_OCI_L2_TRGAS
PACE_OCI_L2_TRGAS·v3.0·dataset

Nitrogen dioxide and ozone air pollution (PACE)

PACE OCI Level-2 Regional Trace Gas Concentrations (NO2, O3) Data, version 3.0
atmosphere NASA OB_CLOUD Level 2 active netCDF-4
In plain English

What it measures. Regional amounts of two air pollutants, nitrogen dioxide and ozone, given as total vertical columns, along with quality and processing flags for each.

How it's made. Derived from the OCI instrument on NASA's PACE satellite as a Level-2 retrieval for specific regions.

How & where you'd use it. Supports air-quality and atmospheric chemistry research and helps correct PACE ocean-color data. Quality flags should be applied to screen out unreliable readings.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › TRACE GASES/TRACE SPECIESAtmosphere › Atmospheric Chemistry

Coverage & cadence

  • Time span2024-03-05 → ongoing
  • Measured byPACE (OCI)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • 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 Trace Gas Concentrations (TRGAS) suite provides key atmospheric column constituents. These trace-gas fields support both atmospheric science (e.g., air-quality and chemistry studies) and ocean-color atmospheric correction. Users should apply the quality and L2 flags to screen cloud effects, high solar-zenith conditions, and other retrieval issues before analysis. Geophysical variables in this suite include: - total_column_no2 – total vertical column nitrogen dioxide (molecules cm⁻²) - total_column_o3– total vertical column ozone (Dobson units) - l2_flags – processing flags (dimensionless) - no2_bit_flags – NO₂ processing flags (dimensionless) - quality_no2 – NO₂ quality flags (dimensionless) - o3_bit_flags – O₃ processing flags (dimensionless) - quality_o3 – O₃ quality flags (dimensionless)

Get the data

pace_oci_l2_trgas_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L2_TRGAS",
    version="3.0",
    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 OB_CLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.