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Full catalog/PACE_OCI_L2_TRGAS_NRT
PACE_OCI_L2_TRGAS_NRT·v3.0·dataset

Air pollution over coasts (NO2, ozone), near real-time (PACE)

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

What it measures. Near-real-time amounts of two air-pollution gases over coastal regions: nitrogen dioxide and ozone, each given as the total column overhead. Quality flags are included to screen out clouds and unreliable readings.

How it's made. Retrieved from the PACE satellite's OCI instrument and delivered quickly using the best-available supporting data, so it is less polished than the final version.

How & where you'd use it. Supports air-quality and atmospheric-chemistry studies near coasts, and also helps correct ocean-color measurements for atmospheric effects.

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

results = earthaccess.search_data(
    short_name="PACE_OCI_L2_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.