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Full catalog/TRPSDL2PANCRSFS
TRPSDL2PANCRSFS·v1·dataset

Smog gas PAN in the air, detailed (Suomi-NPP)

TROPESS CrIS-SNPP L2 Peroxyacetyl Nitrate for Forward Stream, Standard Product V1 (TRPSDL2PANCRSFS) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. How much of the smog-related gas PAN (peroxyacetyl nitrate) is in the air and how it's layered by altitude, plus uncertainty and diagnostic details. PAN forms in polluted, sunlit air and can carry pollution far from its source. This is the full 'standard' version.

How it's made. Retrieved from the CrIS instrument on the Suomi-NPP satellite using a specialized estimation method, producing daily global files at about 14-kilometer detail for a short window in early 2021.

How & where you'd use it. Useful for detailed studies of smog chemistry and long-distance pollution transport, since PAN can release nitrogen pollutants where the air warms up.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › NITROGEN COMPOUNDS › PEROXYACETYL NITRATE

Coverage & cadence

  • Time span2021-02-01 → 2023-05-18
  • Measured bySuomi-NPP (CrIS)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 180, 90
  • StatusCOMPLETE

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 TROPESS CrIS-SNPP L2 Peroxyacetyl Nitrate for Forward Stream, Standard Product contains the vertical distribution of the retrieved atmospheric state of peroxyacetyl nitrate (PAN), formal uncertainties, and diagnostic information measured by the CrIS instrument on the Suomi-NPP satellite. The forward stream standard product is global for the time period from 2021-02-01 to 2021-05-21, when the CrIS-SNPP processing was discontinued. The NASA TRopospheric Ozone and Precursors from Earth System Sounding (TROPESS) project, uses an optimal estimation algorithm, known as the MUlti-SpEctra, MUlti-SpEcies, Multi-SEnsors (MUSES). The data files are written in the netCDF version 4 file format, and each file contains one day of data. The data have a spatial resolution of 14 km (CrIS nadir FOV), and are reported at 16 vertical levels from the surface to 0.1 hPa. The principal investigator for the TROPESS project is Kevin W. Bowman.

Get the data

trpsdl2pancrsfs_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TRPSDL2PANCRSFS",
    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.