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. The meeting opened with a special memorial session dedicated to Arthur Hou, the former GPM Project Scientist, who passed away November 20, 2013. Hou’s friends and colleagues remembered him as an exceptional scientist and leader who was able to build and navigate the international relationships that got the GPM mission off the ground.
Download File:2014 PMM Science Team Meeting Summary from the Earth Observer, November 2014Author(s):Publication Date:11/01/2014
Download File:GPM Mission BrochurePublication Date:11/01/2013
This 17 page flyer provides an overview of the GPM Mission. It describes the technologies used to measure precipitation and the missions scientific goals and societal applications.
"The Global Precipitation Measurement (GPM) mission is an international partnership co-led by NASA and the Japan Aerospace Exploration Agency (JAXA). The mission centers on the deployment of the GPM Core Observatory and consists of a network, or constellation, of additional satellites that together will provide next-generation global observations of precipitation from space. The GPM Core Observatory will carry an advanced radar/radiometer system and serve as a reference standard to unify precipitation measurements from all satellites that fly within the constellation."
Table of Contents:
- Precipitation Measurement Science
- Global Precipitation Measurement Mission
- GPM Core Observatory
- GMI: GPM Microwave Imager
- DPR: Dual-frequency Precipitation Radar
- Spacecraft Design
- Ground System and Data
- GPM Mission Applications: A Global Understanding for a Better Future
Download File:2011 PMM Science Team Meeting Summary from the Earth Observer, March 2012Author(s):Publication Date:03/01/2012
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. During the first three days of the meeting, participants focused on TRMM/ GPM programmatic summaries, international activities, ground validation summaries, and science reports from science team members. In addition to 12 oral presentations, two afternoon poster sessions were held to facilitate discussion of research results in an interactive forum. The final day was devoted to GPM algorithm team meetings. Working groups that focused on hydrology, algorithm development, latent heating, and land-surface characterization met throughout the week.
Download File:GPM: Chapter 6 from "Precipitation: Advances in Measurement, Estimation, and Prediction"Publication Date:03/01/2008
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. Precipitation regulates the global energy and radiation balance through coupling to clouds and water vapor (the primary greenhouse gas) and shapes global winds and atmospheric transport through latent heat release. Surface precipitation directly affects soil moisture and land hydrology and is also the primary source of freshwater in a world that is facing an emerging freshwater crisis. Accurate and timely knowledge of global precipitation is essential for understanding the multi-scale interaction of the weather, climate and ecological systems and for improving our ability to manage freshwater resources and predicting high-impact weather events including hurricanes, floods, droughts and landslides.
In terms of measurements of precipitation, it is critical that data be collected at local scales over a global domain to capture the spatial and temporal diversity of falling rain and snow in meso-scale, synoptic-scale and planetary-scale events. However, given the limited weather station networks on land and the impracticality of making extensive rainfall measurements over oceans, a comprehensive description of the space and time variability of global precipitation can only be achieved from the vantage point of space.
A.Y. Hou, G. Skofronick-Jackson, C. Kummerow, and J. M. Shepherd, Global Precipitation Measurement, Chapter 6 in Precipitation: Advances in Measurement, Estimation and Prediction Editor: Silas Michaelides, Springer-Verlag, March 2008, 540pp, ISBN: 978-3-540-77654-3.
Download File:GPM Ground Validation: Strategy and EffortsKeywords:Publication Date:
The validation of satellite products is classically defined as a ground-based observing strategy intended to assess whether satellite products meet their stated accuracy requirements and objectives. In the case of the Tropical Rainfall Measurement Mission (TRMM), this philosophy was translated to the quasi-continuous operation of four ground radar sites for which TRMM satellite sensor-based and ground-based rainfall products were compared. The findings from these four sites revealed that TRMM products generally met their stated objectives. In addition, a number of lessons have also been learned in the course of these efforts: (a) quality control and careful construction of ground validation datasets is very labor intensive, but methods that make calibration and quality control techniques more efficient continue to improve; (b) despite every effort, ground validation data has its own set of uncertainties, consisting of both biases (currently ~ 5%) and random errors that are difficult to quantify on short time/space scales such as a single satellite overpass; and (c) direct comparison between rainfall estimates from the TRMM Precipitation Radar (PR) and microwave imager (TMI) reveal that instrument differences have regional and seasonal components that require validation results to be interpreted in a similar fashion.
Download File:At the Core: Global Precipitation Measurement MissionPublication Date:11/01/2010
"Next-generation unified precipitation observations from space will refine global data using the latest satellite technology"
An article from the publication Meteorological Technology International. It provides an overview of the GPM mission and it's goals, as well as a description of the Helsinki ground validation field experiment.