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Full catalog/TRMM_2B31
TRMM_2B31·v7·dataset

How much it rained, radar plus microwave (TRMM)

TRMM Combined Precipitation Radar and Microwave Imager Rainfall Profile L2 1.5 hours V7 (TRMM_2B31) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. The best available estimate of rainfall and its vertical structure over the tropics, including details like the average raindrop size and the heat released as rain forms.

How it's made. Created by combining radar and microwave readings from two instruments aboard the TRMM satellite into one merged rainfall product; this is a preserved older version, since superseded by a newer GPM-formatted release.

How & where you'd use it. Supports studies of tropical storms and the global water cycle. Note this version is archived for the historical record rather than active use.

What's measured

ATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD LIQUID WATER/ICEATMOSPHERE › PRECIPITATION › PRECIPITATION AMOUNTATMOSPHERE › PRECIPITATION › PRECIPITATION RATE

Coverage & cadence

  • Time span1997-12-07 → 2015-04-01
  • Measured byTRMM (PR, TMI)
  • Processing levelLevel 2
  • Spatial extent-180, -38, 180, 38
  • 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 last version of the TRMM-formatted, in HDF4 format, Combined (Radar-Radiometer) product, which is in a state of permanent preservation. New version that is consistently processed with Global precipitation Measurement (GPM) algorithms, and in a consistent with GPM HDF5 format, is available under short name 'GPM_2BCMB_TRMM'. The dataset TRMM_2B31 combines data from the TMI and PR to produce the best rain estimate for TRMM. This combined rainfall product is derived from vertical hydrometeor profiles using data from the PR radar and TMI. It also includes computed correlation-corrected, mass-weighted, mean drop diameter and its standard deviation, and latent heating data. Pre-Boost (before 7 August 2001): Temporal Resolution: 91.5 min/orbit ~ 16 orbits/day; Swath Width: 215 km; Horizontal Resolution: 4.3 km Post-Boost (after 24 August 2001): Temporal Resolution: 92.5 min/orbit ~ 16 orbits/day; Swath Width: 247 km; Horizontal Resolution: 5.0 km

Get the data

trmm_2b31_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TRMM_2B31",
    version="7",
    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.