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Full catalog/PACE_OCI_L3M_TRGAS_NRT
PACE_OCI_L3M_TRGAS_NRT·v3.0·dataset

Air pollution gases, near real-time (PACE OCI)

PACE OCI Level-3 Global Mapped Trace Gas Concentrations (NO2, O3) - Near Real-time (NRT) Data, version 3.0
atmosphere NASA OB_CLOUD Level 3 active netCDF-4
In plain English

What it measures. Daily global maps of two pollution-related gases in the air column: nitrogen dioxide and ozone, totaled from the surface up through the atmosphere.

How it's made. Derived quickly (near real-time) from the OCI instrument on NASA's PACE satellite, using best-available weather and ozone inputs, so the calibration is rougher than the final product.

How & where you'd use it. Supports air-quality and atmospheric chemistry studies, and helps correct ocean-color measurements; users should apply the included quality flags to screen out clouds and bad retrievals before relying on it.

What's measured

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

Coverage & cadence

  • Time span2024-03-05 → ongoing
  • Measured byPACE (OCI)
  • Processing levelLevel 3
  • 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 Ocean Biology DAAC produces near real-time (NRT) products using the best-available combination of ancillary data from meteorological and ozone data. As such, the inputs and the calibration used are less than optimal. Near real-time products provide a snapshot of the data during a short time period within a single orbit. 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)

Get the data

pace_oci_l3m_trgas_nrt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PACE_OCI_L3M_TRGAS_NRT",
    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.