Precipitation Processing System (PPS) servers will be down for extended maintenance from Tuesday, September 22nd through Thursday September 24th. During this time the PPS websites, the PMM Publisher API, and the GPM research data server (arthurhou) will be unavailable. The GPM near real-time server (jsimpson) and satellite data collection will not be affected. Click here to learn more.
GPM flying over Earth with a data swath visualized.

Creation of Data Products

Precipitation Processing System (PPS)

PPS provides real-time processing and post-processing of the TRMM science data is performed by the TRMM Science Data and Information System (TSDIS). Working with the TRMM principal investigators and science algorithm developers, PPS maintains the operational science data processing system and ensures the timely processing of all TRMM science instrument data. During routine operations, raw instrument data is received in near real-time by PPS and then processed by the first tier of science algorithms to produce calibrated, swath-level instrument data. Using this calibrated, swath-level instrument data, the second tier of algorithms are used to compute geophysical parameters, such as precipitation rate, also at the swath-level resolution. At the final stage of processing, the third tier algorithms produce gridded geophysical parameters from the first- and second-tier instrument data. All TRMM products are archived and distributed by the Goddard Distributed Active Archive Center (GES DISC DAAC). For further information on PPS operations, please visit the PPS homepage.

PPS Logo


Data Products & Description

In order to satisfy opposing requirements for early data distribution and the highest possible data quality, TRMM will reprocess all products with improved algorithms approximately once per year. This section, aside from presenting general product information, updates the performance of each algorithm as information becomes available to the science team. Data users should check this site before working with any TRMM data, and occasionally thereafter as more information becomes available. All information is tied to the data version number as distributed by the GES DISC DAAC.

TRMM Ground Validation (GV)

The function of the TRMM GV program at the NASA/Goddard Space Flight Center is to provide support for TRMM, in connection with the ground based validation of the TRMM satellite observations. The TRMM Satellite Validation is the focal point for the planning and implementation of a broad and integrated observational program of precipitation and related climate research, designed to meet the specific science validation objectives established by the TRMM science team, and which are also consistent with programmatic requirements established by NASA Headquarters. For pre-launch algorithm development and post-launch product evaluation, GPM supports a range of multi-faceted Ground Validation (GV) program activities. Read more about GV activities in the Ground Validation Portal. Ground validation data will be available through the GV Data Access Page.