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Full catalog/LPRM_TMI_NT_SOILM3
LPRM_TMI_NT_SOILM3·v001·dataset

How wet the soil is at night (TRMM, 25 km)

TMI/TRMM surface soil moisture (LPRM) L3 1 day 25 km x 25 km nighttime V001 (LPRM_TMI_NT_SOILM3) at GES DISC
land NASA GES_DISC Level 3
In plain English

What it measures. How wet the top layer of soil is, measured during nighttime passes, along with land surface temperature and the water held in vegetation, on a global 25 km grid.

How it's made. Derived from the TMI microwave imager on the TRMM satellite using the Land Parameter Retrieval Model, gridded into daily nighttime maps; it builds on TMI brightness-temperature readings.

How & where you'd use it. Useful for drought monitoring, agriculture, and water-cycle and climate studies; the nighttime timing helps avoid some daytime measurement complications. Covers 1997 to 2015, when TRMM was retired.

What's measured

LAND SURFACE › SURFACE THERMAL PROPERTIES › SKIN TEMPERATURELAND SURFACE › SOILS › SOIL MOISTURE/WATER CONTENTBIOSPHERE › VEGETATION › PLANT CHARACTERISTICS › VEGETATION WATER CONTENT

Coverage & cadence

  • Time span1997-12-07 → 2015-04-08
  • Measured byTRMM (TMI)
  • Processing levelLevel 3
  • Spatial extent-180, -40, 180, 40
  • 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

TMI/TRMM surface soil moisture (LPRM) L3 1 day 25 km x 25 km nighttime V001 is Level 3 (gridded) data set. Its land surface parameters, surface soil moisture, land surface (skin) temperature, and vegetation water content, are derived from passive microwave remote sensing data from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), using the Land Parameter Retrieval Model (LPRM). There are two files per day, one daytime and one nighttime, archived as two different products. This document is for the nighttime product. The data set covers the period from December 1997 to April 2015 (when the instruments on the TRMM satellite were shut down in preparation for its reentry into the earth's atmosphere). The LPRM is based on a forward radiative transfer model to retrieve surface soil moisture and vegetation optical depth. The land surface temperature is derived separately from TMI's Ka-band (37 GHz). A unique feature of this method is that it can be applied at any microwave frequency, making it very suitable to exploit all the available passive microwave data from various satellites. Input data are from the TMI Brightness Temperatures (1B-11) product, nighttime passes, as processed using LPRM (i.e., LPRM/TMI/TRMM Level 2 product, LPRM_TMI_SOILM2_V001).

Get the data

lprm_tmi_nt_soilm3_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="LPRM_TMI_NT_SOILM3",
    version="001",
    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.