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Full catalog/TRPSDL2NH3CRSFS
TRPSDL2NH3CRSFS·v1·dataset

Ammonia gas in the air (forward stream)

TROPESS CrIS-SNPP L2 Ammonia for Forward Stream, Standard Product V1 (TRPSDL2NH3CRSFS) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. How much ammonia gas is in the air and how it is distributed from the ground up through the atmosphere, along with uncertainty estimates for each measurement.

How it's made. Retrieved from the CrIS infrared instrument on the Suomi-NPP satellite using NASA's TROPESS optimal-estimation method, with one file per day covering early 2021.

How & where you'd use it. Helps scientists study agricultural emissions and air pollution, since ammonia mostly comes from farming and affects air quality.

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

Get the data

trpsdl2nh3crsfs_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TRPSDL2NH3CRSFS",
    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.