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Full catalog/TRPSDL2HDOCRSFS
TRPSDL2HDOCRSFS·v1·dataset

Heavy-water vapor for the water cycle, detailed (Suomi-NPP)

TROPESS CrIS-SNPP L2 Deuterated Water Vapor for Forward Stream, Standard Product V1 (TRPSDL2HDOCRSFS) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. The amount of a rare 'heavy' form of water vapor (called HDO) and how it's layered through the atmosphere from the surface upward. This heavy-water signal is a detailed fingerprint of how water moves and changes.

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. This particular run covers a short window in early 2021.

How & where you'd use it. Helps scientists trace the water cycle, since the ratio of heavy to ordinary water vapor reveals how water evaporates, condenses, and travels through the atmosphere.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › HYDROGEN COMPOUNDS › HYDROGEN-DEUTERIUM OXIDE

Coverage & cadence

  • Time span2021-02-01 → 2021-05-21
  • 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 Deuterated Water Vapor for Forward Stream, Standard Product contains the vertical distribution of the retrieved atmospheric state of semi-heavy water (HDO), 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 17 vertical levels from the surface to 0.1 hPa. The principal investigator for the TROPESS project is Kevin W. Bowman.

Get the data

trpsdl2hdocrsfs_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TRPSDL2HDOCRSFS",
    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.