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Full catalog/GPM_3PR
GPM_3PR·v07·dataset

Rainfall radar statistics, monthly (TRMM)

GPM PR on TRMM Reflectivity, Precipitation Statistics, Histograms, at Surface and Fixed Heights, 1 month 5x5 and 0.25x0.25 degree V07 (GPM_3PR) at GES DISC
atmosphere NASA GES_DISC Level 3
In plain English

What it measures. Monthly summaries of rainfall as seen by radar, including how often rain occurred, average rain rates, distributions of rain intensity, and related statistics, organized on global grids.

How it's made. Built from the TRMM satellite's Precipitation Radar measurements, reprocessed into a newer GPM-consistent format and condensed into monthly grid statistics.

How & where you'd use it. Used to study rainfall patterns, including how much and how often it rains in different regions, supporting climate and water-cycle research.

What's measured

ATMOSPHERE › PRECIPITATION › PRECIPITATION RATE

Coverage & cadence

  • Time span1997-12-01 → 2015-04-01
  • Measured byTRMM (PR)
  • Processing levelLevel 3
  • Spatial extent-180, -67, 180, 67
  • 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

This is the new (GPM-formated) TRMM product. It replaces the old TRMM_3A25,3A26 Version 07 is the current version of the data set. Older versions will no longer be available and have been superseded by Version 07. This is the GPM-like formatted TRMM Precipitation Radar (PR) monthly gridded data, first released with the "V8" TRMM reprocessing. The TRMM radar Level 3 grids are now consistent with the GPM Dual-frequency Precipitation Radar (DPR). The closest ancestor of this dataset was the monthly radar statistics 3A25. This product consists of monthly statistics of the PR measurements at 0.25x0.25 degrees, and monthly histograms and statistics at 5x5 degrees, horizontal resolution. The objective of the algorithm is to calculate various daily statistics from the level 2 PR output products. Four types of statistics are calculated: 1. Probabilities of occurrence (count values) 2. Means and standard deviations 3. Histograms 4. Correlation coefficients In all cases, the statistics are conditioned on the presence of rain or some other quantity such as the presence of stratiform rain or the presence of a bright-band. For example, to compute the unconditioned mean rain rate, the conditional mean must be multiplied by the probability of rain which, in turn is calculated from the ratio of rain counts to the total number of observations in the box of interest. The grids are in the Planetary Grid 2 structure matching the Dual-frequency PR on the core GPM observatory that covers 67S to 67N degrees of latitudes. The low resolution 5x5 deg grid covers 70S to 70N. Areas beyond the ±40 degrees of latitudes are padded with empty grid cells.

Get the data

gpm_3pr_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GPM_3PR",
    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.