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Full catalog/GPM_2AGPROFNOAA21ATMS
GPM_2AGPROFNOAA21ATMS·v07·dataset

How much rain and snow fell (microwave, NOAA-21)

GPM ATMS on NOAA-21 (GPROF) Radiometer Precipitation Profiling L2A 1.5 hours 17 km V07 (GPM_2AGPROFNOAA21ATMS) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Estimates of how much rain and snow fell, along with related precipitation details, derived from microwave readings as the satellite passes overhead.

How it's made. Produced by the GPROF algorithm using the ATMS microwave sensor on the NOAA-21 satellite, which matches observed signals against a database of known rain profiles to estimate precipitation.

How & where you'd use it. Contributes to global precipitation tracking, useful for weather monitoring, flood awareness, and water-cycle studies.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPORATMOSPHERE › PRECIPITATION

Coverage & cadence

  • Time span2023-02-01 → ongoing
  • Measured byNOAA-21 (ATMS)
  • 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

Version 07 is the current version of the data set. The 2AGPROF (also known as, GPM GPROF (Level 2)) algorithm retrieves consistent precipitation and related science fields from the following GMI and partner passive microwave sensors: GMI, SSMI (DMSP F15), SSMIS (DMSP F16, F17, F18) AMSR2 (GCOM-W1), TMI MHS (NOAA 18&19, METOP A&B), ATMS (SNPP and NOAA-21). This provides the bulk of the 3-hour coverage achieved by GPM. For each sensor, there are near-realtime (NRT) products, standard products, and climate products. These differ only in the amount of data that are available within 3 hours, 48 hours, and 3 months of collection, as well as the ancillary data used. The NRT product uses GANAL forecast fields. Standard products use the GANAL analysis product, while the climate product uses ECMWF reanalysis in order to allow for consistent data records with earlier missions. These earlier data may be archived separately. The main strength of the product is the large sampling provided. The GPM radiometer algorithms are Bayesian-type algorithms. These algorithms search an a-priori database of potential rain profiles and retrieve a weighted average of these entries based upon the proximity of the observed brightness temperature (Tb) to the simulated Tb corresponding to each rain profile. By using the same a-priori database of rain profiles, with appropriate simulated Tb for each constellation sensor, the Bayesian method is completely parametric and thus well suited for GPM's constellation approach. The a-priori information will be supplied by the combined algorithm supplied by GPM's core satellite as soon after launch as feasible. Databases for V0 of the algorithm had to be constructed from various sources as described in the ATBD. The solution provides a mean rain rate as well as the vertical structure of cloud and precipitation hydrometeors and their uncertainty.

Get the data

gpm_2agprofnoaa21atms_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GPM_2AGPROFNOAA21ATMS",
    version="07",
    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.