Articles and Other

NASA produces a GIS translation of IMERG for various accumulation periods. The GIS translation maintains the 0.1-degree spatial resolution of the original HDF5 data product. In July 2023, Version 7 IMERG was released in both HDF5 and GIS formats. In April 2019, Version 6 of IMERG had been released, covering June 2000 to 2019. The long- duration archive for all versions starting with Version 6 is a boon to scientific research and provides a training set for near real-time applications such as disaster monitoring.

1AGMI contains unpacked packet data from GMI science data from the GMI passive
microwave instrument flown on the GPM satellite. Swath S1 has 9 channels which are
similar to TRMM TMI (10V 10H 19V 19H 23V 37V 37H 89V 89H). Swath S2 has 4
channels similar to AMSU-B (166V 166H 183+/-3V 183+/-8V). Data for both swaths
is observed in the same revolution of the instrument. Swath S3 has ScienceDataHeader.
Swath S4 has full rotation for low freq channels (S1). Swath S5 has full rotation for high
freq channels (S2).

This document describes the basic idea of DPR data processing. It was originally written for the algorithm used in the at-launch version (V03). The algorithm has been modified and improved since then. Although the basic idea of data processing remains the same, the actual flow of processing, in particular that in the solver module, has changed substantially. As a result, some part of description in Section 3.1 may not be relevant any more.

The Integrated Multi-satelliE Retrievals for GPM (*IMERG*) is the unified U.S. algorithm that provides the multi-satellite precipitation product for the U.S. GPM team.  The precipitation estimates from the various precipitation-relevant satellite passive microwave (PMW) sensors comprising the GPM constellation are computed using the 2017 version of the Goddard Profiling Algorithm (GPROF2017), then gridded, intercalibrated to the GPM Combined Radar Radiometer Analysis product (with GPCP climatological calibration), and combined into half-hourly 0.1°x0.1° fields.

This document describes the algorithm and processing sequence for the Integrated Multi-satellitE Retrievals for GPM (IMERG).  This algorithm is intended to intercalibrate, merge, and interpolate “all” satellite microwave precipitation estimates, together with microwave-calibrated infrared (IR) satellite estimates, precipitation gauge analyses, and potentially other precipitation estimators at fine time and space scales for the TRMM and GPM eras over the entire globe.

This excerpt from the November 2014 edition of The Earth Observer provides a summary of the activities at the PMM Science Team Meeting which took place from August 4 - 7, 2014. The PMM program supports scientific research, algorithm development, and ground-based validation activities for the Tropical Rainfall Measuring Mission (TRMM) and the Global Precipitation Measurement (GPM) Core Observatory that launched on February 27, 2014.

This excerpt from the March-April 2012 edition of The Earth Observer provides a summary of the activities at the PMM Science Team Meeting which took place from November 7 - 10 2011. The meeting brought together over 150 participants from 10 countries, and included representatives from NASA, JAXA, the National Oceanic and Atmospheric Administration (NOAA), universities, industry, and other international partner agencies.

Excerpt:

Observations of the space-time variability of precipitation around the globe are imperative for understanding how climate change affects the global energy and water cycle (GWEC) in terms of changes in regional precipitation characteristics (type, frequency, intensity), as well as extreme hydrologic events, such as floods and droughts. The GWEC is driven by a host of complex processes and interactions, many of which are not yet well understood. Precipitation, which converts atmospheric water vapor into rain and snow, is a central element of the GWEC.

Detailed specifications document for the Dual-Frequency, Dual-Polar, Doppler Radar (D3R)