TRMM 3B42: 3-Hourly Precipitation Estimates

Dataset Availability
1998-01-01T00:00:00 - Present
Dataset Provider
Earth Engine Snippet
precipitation geophysical weather climate rainfall trmm nasa jaxa 3-hourly


The Tropical Rainfall Measuring Mission (TRMM) is a joint mission between NASA and the Japan Aerospace Exploration Agency (JAXA) designed to monitor and study tropical rainfall. The 34B2 product contains a gridded, TRMM-adjusted, merged infrared precipitation (mm/hr) and RMS precipitation-error estimate, with a 3-hour temporal resolution and a 0.25 degree spatial resolution.

See the algorithm description and the file specification for details.


0.25 arc degrees


Name Units Min Max Description
precipitation mm/hr 0 100

Merged microwave/IR precipitation estimate

relativeError mm/hr 0 100

Merged microwave/IR precipitation random error estimate


Flag to show source of data

HQprecipitation mm/hr 0 100

Pre-gauge-adjusted microwave precipitation estimate

IRprecipitation mm/hr 0 100

Pre-gauge-adjusted infrared precipitation estimate

satObservationTime Minutes -90 90

Satellite observation time minus the time of the granule. In case of overlapping satellite observations, the two or more observation times are equal-weighting averaged.

Image Properties

Image Properties

Name Type Description
StartGranuleDateTime STRING

Granule start date and time

StopGranuleDateTime STRING

Granule end date and time

Terms of Use

Terms of Use

This dataset is in the public domain and is available without restriction on use and distribution. See NASA's Earth Science Data & Information Policy for additional information.


  • Adler, R.F., G.J. Huffman, A. Chang, R. Ferraro, P. Xie, J. Janowiak, B. Rudolf, U. Schneider, S. Curtis, D. Bolvin, A. Gruber, J. Susskind, P. Arkin, E.J. Nelkin, 2003: The Version 2 Global Precipitation Climatology Project (GPCP) Monthly Precipitation Analysis (1979-Present). J. Hydrometeor., 4(6), 1147-1167.

  • Huffman, G.J., 1997: Estimates of Root-Mean-Square Random Error for Finite Samples of Estimated Precipitation, J. Appl. Meteor., 1191-1201.

  • Huffman, G.J., 2012: Algorithm Theoretical Basis Document (ATBD) Version 3.0 for the NASA Global Precipitation Measurement (GPM) Integrated Multi-satellitE Retrievals for GPM (I-MERG). GPM Project, Greenbelt, MD, 29 pp.

  • Huffman, G.J., R.F. Adler, P. Arkin, A. Chang, R. Ferraro, A. Gruber, J. Janowiak, A. McNab, B. Rudolph, and U. Schneider, 1997: The Global Precipitation Climatology Project (GPCP) Combined Precipitation Dataset, Bul. Amer. Meteor. Soc., 78, 5-20.

  • Huffman, G.J., R.F. Adler, D.T. Bolvin, G. Gu, E.J. Nelkin, K.P. Bowman, Y. Hong, E.F. Stocker, D.B. Wolff, 2007: The TRMM Multi-satellite Precipitation Analysis: Quasi-Global, Multi-Year, Combined-Sensor Precipitation Estimates at Fine Scale. J. Hydrometeor., 8(1), 38-55.

  • Huffman, G.J., R.F. Adler, M. Morrissey, D.T. Bolvin, S. Curtis, R. Joyce, B McGavock, J. Susskind, 2001: Global Precipitation at One-Degree Daily Resolution from Multi-Satellite Observations. J. Hydrometeor., 2(1), 36-50.

  • Huffman, G.J., R.F. Adler, B. Rudolph, U. Schneider, and P. Keehn, 1995: Global Precipitation Estimates Based on a Technique for Combining Satellite-Based Estimates, Rain Gauge Analysis, and NWP Model Precipitation Information, J. Clim., 8, 1284-1295.

Explore in Earth Engine

var dataset = ee.ImageCollection('TRMM/3B42')
                  .filter('2018-04-01', '2018-04-10'));
var precipitation =['precipitation', 'HQprecipitation', 'IRprecipitation']);
var precipitationVis = {
  min: 0.0,
  max: 12.0,
  gamma: 5.0,
Map.setCenter(-79.98, 23.32, 4);
Map.addLayer(precipitation, precipitationVis, 'Precipitation');