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Full catalog/TMI-REMSS-L3U-v7.1a
TMI-REMSS-L3U-v7.1a·v7.1a·dataset

Sea surface temperature from microwave (TRMM)

GHRSST Level 3U Global Subskin Sea Surface Temperature from TMI onboard TRMM satellite
ocean NASA POCLOUD Level 3 netCDF-4
In plain English

What it measures. Sea surface temperature in the global tropics, measured just below the very top skin of the ocean, along the satellite's track.

How it's made. Retrieved from microwave signals naturally emitted by the ocean, recorded by the TMI instrument on the TRMM satellite and processed with a roughness-correction algorithm; unlike infrared methods, microwaves can see through clouds.

How & where you'd use it. Monitoring tropical ocean temperatures for weather and climate research, valuable because it works even in cloudy conditions that block infrared sensors.

What's measured

OCEANS › OCEAN TEMPERATURE › SEA SURFACE TEMPERATURE › Skin Sea Surface Temperature

Coverage & cadence

  • Time span1997-12-08 → 2015-01-01
  • Measured byTRMM (TMI)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusCOMPLETE

What you can do with it

  • Watch sea-surface temperature and marine heatwaves
  • Spot algal blooms and ocean-colour shifts
  • Support fisheries and coastal monitoring
Official description

The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) is a well calibrated passive microwave radiometer, similar to the Special Sensor Microwave Imager (SSM/I), that contains lower frequency channels required for sea surface temperature (SST) retrievals. The TRMM is part of the NASA's mission to planet Earth, and is a joint venture between NASA and the Japan Aerospace Exploration Agency (JAXA) to measure precipitation, water vapor, sea surface temperature (SST) and surface wind in the global tropical regions and was launched in 27 November 1997 from the Tanegashima Space Center in Tanegashima, Japan. The TRMM satellite travels west to east in a 402 km altitude semi-equatorial processing orbit that results in day-to-day changes in the observation time of any given earth location between 38S and 38N. Remote Sensing Systems (REMSS) has produced a Version-7.1a TMI SST dataset for the Group for High Resolution Sea Surface Temperature (GHRSST) by applying an algorithm to the 10.7 GHz channel through a removal of surface roughness effects. In contrast to infrared SST observations, microwave retrievals can be measured through clouds, which are nearly transparent at 10.7 GHz. Microwave retrievals are also insensitive to water vapor and aerosols. The algorithm for retrieving SSTs from radiometer data is described in "AMSR Ocean Algorithm."

Get the data

tmi-remss-l3u-v7.1a_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TMI-REMSS-L3U-v7.1a",
    version="7.1a",
    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 POCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.