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Full catalog/GPM_1BTMI
GPM_1BTMI·v07·dataset

Raw microwave brightness temperatures (TRMM)

GPM TMI on TRMM Brightness Temperatures L1B 1.5 hours 13 km V07 (GPM_1BTMI) at GES DISC
land NASA GES_DISC Level 1B
In plain English

What it measures. Raw brightness temperatures, which are how warm different surfaces and the atmosphere look to a microwave sensor across several frequencies. These are basic calibrated readings, not rainfall amounts.

How it's made. Produced by converting raw counts from the TMI microwave sensor on the TRMM satellite into calibrated temperatures, with corrections applied but no extra smoothing.

How & where you'd use it. A low-level input used to derive rainfall and other products; most people use the higher-level precipitation products built from it rather than these raw temperatures.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › SENSOR COUNTSSPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › THERMAL INFRARED › RADIANCE @ 10.8UMSPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › THERMAL INFRARED › RADIANCE @ 12.0UMSPECTRAL/ENGINEERING › PLATFORM CHARACTERISTICS › ATTITUDE CHARACTERISTICSSPECTRAL/ENGINEERING › SENSOR CHARACTERISTICS › VIEWING GEOMETRY › SATELLITE LOCAL ZENITH ANGLESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › SENSOR COUNTSSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE IMAGERY › RADIANCE @ 0.63UMSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span1997-12-07 → 2015-04-08
  • Measured byTRMM (TMI)
  • Processing levelLevel 1B
  • Spatial extent-180, -38, 180, 38
  • StatusCOMPLETE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

This is the new (GPM-formated) TRMM product. It replaces the old TRMM_1B11 Version 07 is the current version of the data set. Previous versions have been superseded by Version 07. This dataset contains TRMM Micrwave Imager (TMI) L1B calibrated radiances in terms of Brightness Temperatures. The TMI calibration algorithm (1B11) converts the radiometer counts to antenna temperatures by applying a linear relationship of the form Ta = c1 + c2 x count. The coefficients are provided by the instrument contractor. Antenna temperatures are corrected for cross-polarization and spill over to produce brightness temperatures (Tb), but no antenna beam pattern correction or sample to pixel averaging are performed. Temperatures are provided at 104 scan positions for the low frequency channels and 208 scan positions at 85 GHz. There are four samples per pixel (3 -dB beamwidth) at 10 GHz, two samples at 19, 22, and 37 GHz, and one sample per pixel for the 85 GHz. Data Flow Description Changes in horizontal resolution resulting from the TRMM boost that occurred on 24 August 2001: Pre-Boost (before 7 August 2001): Temporal Resolution: 91.5 min/orbit ~ 16 orbits/day; Swath Width: 760 km; Horizontal Resolution: ~13 km Post-Boost (after 24 August 2001): Temporal Resolution: 92.5 min/orbit ~ 16 orbits/day; Swath Width: 878 km; Horizontal Resolution: ~13 km

Get the data

gpm_1btmi_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GPM_1BTMI",
    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.