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Full catalog/TRMM_3A12
TRMM_3A12·v7·dataset

How much it rained (TRMM microwave, monthly)

TRMM Microwave Imager Precipitation Profile L3 1 month 0.5 degree x 0.5 degree V7 (TRMM_3A12) at GES DISC
atmosphere NASA GES_DISC Level 3
In plain English

What it measures. Monthly global averages of how much it rained, including surface rain rate and the amounts of water, ice, snow, and other moisture stacked through 28 layers of the atmosphere. Reported in half-degree grid squares.

How it's made. Produced from the TRMM satellite's Microwave Imager observations of precipitation, averaged over each month onto a grid.

How & where you'd use it. Useful for studying rainfall patterns and the vertical structure of storms; note this older dataset has been superseded by a newer GPM-era equivalent.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROFILESATMOSPHERE › PRECIPITATION › SOLID PRECIPITATION › CONVECTIVE SURFACE PRECIPITATION RATEATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD LIQUID WATER/ICEATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD PRECIPITABLE WATERATMOSPHERE › PRECIPITATION › PRECIPITATION RATEATMOSPHERE › PRECIPITATION › LIQUID PRECIPITATION › RAINATMOSPHERE › ATMOSPHERIC RADIATION › ATMOSPHERIC HEATING

Coverage & cadence

  • Time span1997-12-01 → 2015-03-31
  • Measured byTRMM (TMI)
  • Processing levelLevel 3
  • Spatial extent-180, -40, 180, 40
  • 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 new equivalent for this dataset should be searched for as "GPM_3GPROFTRMMTMI_CLIM". This product contains global monthly means of surface precipitation rate, rain rate, convective surface precipitation rate and 28 vertical layers of hydrometeor contents (cloud liquid water, rain water, cloud ice liquid water, snow liquid water, graupel liquid water and latent heating) on 0.5 x 0.5 degree grids.

Get the data

trmm_3a12_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TRMM_3A12",
    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.