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Full catalog/TRPSYL2NH3CRSFS
TRPSYL2NH3CRSFS·v1·dataset

Ammonia in the air, summary (Suomi-NPP)

TROPESS CrIS-SNPP L2 Ammonia for Forward Stream, Summary Product V1 (TRPSYL2NH3CRSFS) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. How much ammonia is in the air and how it is distributed through the atmosphere from the surface up, with uncertainty estimates. This is the streamlined 'summary' version.

How it's made. Derived from the CrIS infrared sounder on the Suomi-NPP satellite, processed by the TROPESS project's optimal-estimation method into daily global files (this stream ran Feb to May 2021).

How & where you'd use it. Useful for studying air quality and pollution, since ammonia comes largely from farming and fertilizer and contributes to harmful fine-particle haze.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › NITROGEN COMPOUNDS › AMMONIA

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 Ammonia for Forward Stream, Summary Product contains the vertical distribution of the retrieved atmospheric state of ammonia (NH3), and formal uncertainties 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 15 vertical levels from the surface to 0.1 hPa. The principal investigator for the TROPESS project is Kevin W. Bowman.

Get the data

trpsyl2nh3crsfs_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TRPSYL2NH3CRSFS",
    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.